Summer 2019
WWW.PCI.ORG
ASCENT ®
DESIGNING WITH PRECAST
HOW PRECAST BUILDS FOR THE BIG ONE Precast Concrete Passes the Resilience Test
“The precast panels allowed us to incorporate progressive collapse into the project without a secondary structural system and to provide durable, extremely low maintenance exterior and interior finishes.” Robin Henry, Architect The Johnson McAdams Firm
Fabricated Army Tough An all precast system with progressive collapse blast design met the U.S. Army Corps of Engineers’ high standards for four four-story barracks at Camp Shelby. The thermally efficient precast enclosure system, which acts as air, water and vapor barrier, features insulation and conduit integrally cast within the panels. Load-bearing walls combined with long-span double tee flooring serve as both structure and facade featuring embedded brick, and limestone, exposed aggregate and durable interior finishes. The structures offer a 100-year service life with the added bonus of hurricane protection for the surrounding communities.
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Operational Readiness Training Complex Camp Shelby, MS Johnson McAdams Firm Photos: John Thomas Photography
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CONTENTS CONTENTS
FEATURES
ASCENT® IS A PUBLICATION OF PCI ASCENT® IS A PUBLICATION OF PCI Executive Editor: Tom Bagsarian Executive Editor: TomCraig Bagsarian Managing Editors: Shutt and Monica Schultes Managing Editor: Craig Editors: Becky King, Shutt and Nikole Clow Contributor: Monica Schultes Ascent Layout Concept: Ascent Layout Concept: MB Piland Advertising + Marketing MB Piland Advertising + Marketing Graphic Designers: Graphic Designers: Russell Duncan and Justin Goode Russell Duncan and Justin Goode Sales: AdAd Sales: Trice Turner Trice Turner Manager, Business Development Sales Specialist 312-583-6784 312-583-6784 sales@pci.org sales@pci.org Reprint Sales andand Subscriptions: Reprint Sales Subscriptions: Tom TomBagsarian Bagsarian tbagsarian@pci.org tbagsarian@pci.org Precast/Prestressed Concrete Institute: Precast/Prestressed Concrete Institute: Robert Risser, PE, President and CEO Robert Risser, PE, President and CEO Industry Technical Review Team: Peter Finsen, Industry Technical Review Team: Peter Finsen, Corey Greika, Thomas Ketron, Ed Knowles, Jane CoreyMark Greika, Thomas Ketron, Martin, Mark Martin, McKeny, Brian Miller,Jane Kim Wacker, McKeny, Brian Miller, and Kim Wacker and Roger Becker
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A Renaissance Project
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Next-Generation Precast Insulated Wall Panels
Research aims to develop materials and design for precast insulated wall panels that double the thermal performance and reduce weight by half, without increasing costs.
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Perkins+Will Architects
The interdisciplinary architecture and design firm places a focus on higher education to bolster ideas and buildings that honor broader societal goals.
Precast Concrete Meets Today's Student Housing Demands
As the demand for on-campus student housing remains high, universities are embracing precast concrete systems as a solution.
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Making The Case for a Precast Stadium
POSTMASTER: Send address changes POSTMASTER: Send address changes to to Ascent, 200 W.200 Adams St., Suite 2100,2100, Ascent, W. Adams St., Suite Chicago, IL 60606. Chicago, IL 60606.
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Universities Strive to be 'Nimble'
Periodical postage paidpaid at Chicago, IL andIL and Periodical postage at Chicago, additional mailing offices. additional mailing offices.
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Ascent (Vol. 29, No. 1, ISSN 10796983) Ascent (Vol. 29, No. 3, ISSN 10796983) is published is published quarterly by the Precast/ quarterly by the Precast/Prestressed Concrete Prestressed Concrete Institute, 200 W. Adams Institute, 200 W. Adams St., Suite 2100, St., Suite 2100, Chicago, IL 60606. Chicago,2019 IL 60606. Copyright Copyright 2019 Concrete Institute Precast/Prestressed stressed Institute If Precast/Pre you have a project to beConcrete considered, If you have a project to be considered, send information to Tom Bagsarian. tbagsarian@pci.org send information to Tom Bagsarian at
FEATURES 4
Case Study: Florida International University Projects, Miami
Located in a High-Velocity Hurricane Zone, FIU turns to precast concrete to build a resilient and beautiful campus.
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Communities Safe Insight
News about precast concrete, producers, programs, and projects46 .
More Than JustArizona Architecture 64 18University Profile: State University
HOW PRECAST ASCENT BUILDS ®
DESIGNING WITH PRECAST
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Summer 2019
Precast concrete architectural and structural components help designers meet the demands of evolving teaching methods. Page 30: The Mashouf Wellness Center Photo: Jeremy Bittermann.
FEMA sets guidelines forevolution designers Tornado Michael D. Moss discusses the ofin precast concrete. Alley in order to build the safest, most effective 6 Headlines storm shelters possible.
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DELIVERING SOLUTIONS FOR
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HOW PRECAST BUILDS FOR THE BIG ONE
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Army Advances with Precast Concrete
Barracks constructed with precast concrete ensure the safety of cybersecurity soldiers at Fort Gordon in Augusta, Ga.
PCI Fire Standard Added to IBC 2021 The ICC has accepted PCI’s consensusdeveloped fire standard in the 2021 International Building Code.
DEPARTMENTS
USC Village is a visual testament to the versatility and complex
24architectural Sandy Resiliency andconstruction. Renewal design of precast
Program:Education PrecastOpportunities Concrete Protects Continuing Critical Infrastructure After Hurricane Sandy hit theDesign U.S. inResources 2012, Precast/Prestressed Concrete
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Insight
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Continuing Education Opportunities
Robert Shade considers the usefulness of precast concrete for building storm shelters.
State-by-state directory of PCI-Certified Plants, including a guide to product 9 groups and categories for reference in upcoming projects.
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On the cover: Florida International Student Academic Support Center. Photo: Robin Hill.
On the cover: Parking Structure 5, California State University Photo: Kyle Jeffers, courtesy of as.wi19.TOC.indd Dreyfuss 3 + Blackford Architecture.
provide a functional space for students.
2018 Sidney Freedman Craftsmanship Award
Visitawww.pci.org Body for Knowledge resources. need for newfor storm-resistant building construction arose to include precast concrete 70 PCI-Certified Plants Directory as a key player.
Precast Concrete Passes the Resilience Test
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Builders capitalize on precast concrete components to rapidly complete Canvas Stadium within an extremely aggressive building schedule.
DEPARTMENTS 10 Precast Concrete FEMA Shelters Keep
WWW.PCI.ORG
HIGHER EDUCATION
The new student housing at Longwood University, shown in a rendering, will feature a traditional look that was achieved with loadbearing precast concrete wall panels that tie back to the existing steel frame. Rendering: Little
designs storm sheltersand for allows schoolsstudents ASUHuckabee teams up with the PCI Foundation, bothstudio meettorequired regulations in itsthat precast choose their projects. and
tbagsarian@pci.org. WInter 2019
A residence hall at Fayetteville State University come together in a year thanks to hollow-core concrete slabs, changing the way we design buildings.
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Precast/Prestressed Concrete Design Resources
Resiliency is the New Sustainability
PCI-Certified Erectors Directory Sustainability means more than just carbon
Visit pci.org for Body of Knowledge resources State-by-state of PCI-Certified Erectors, including a guide to footprint; itdirectory also includes how resilient a classifications and specification fordisasters. reference in projects. building can beainguide the face of natural
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California Universities Embrace Cool Style Precast concrete has become essential in California construction because of the high level of seismic activity in the area, but that doesn’t mean it all has to look the same.
University Profile: Tulane
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At Tulane University in New Orleans, La., students discoverASCENT, how WINTER precast 2019concrete is instrumental in addressing regional water infrastructure challenges. 12/19/18 1:50 PM
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DESIGNING WITH PRECAST
INSIGHT THOUGHTS FROM A TORNADO VETERAN Tornados are a way of life for many people, including myself, who was born and raised in Oklahoma. I have been perilously close to more than I care to remember.
ROBERT SHADE SALES MANAGER
CORESLAB STRUCTURES
My mother threw me into a closet when I was around eight years old as a small tornado jumped around our house in Oklahoma City. It turned my best friend’s swing set into a pretzel and missed mine, but it caused a large oak tree to land next to the closet we were in. We moved a few miles away to Mustang and saw many twisters from a distance, but one got so close we went inside an underground shelter that had water issues caused by soil issues, which is common in Oklahoma. This is why homes in the state do not have underground basements. Not once, but twice, I helped my aunt pick up what was left of her belongings in Moore. In 1999, a tornado lifted her roof off her home while she was in a closet. Just four years later, she was at work and returned home to find an exterior wall was on top of the shelter to which she would have escaped if she had been home. Saddest of all, our hearts were broken in 2013 when we learned five kids were found dead in the rubble of a tornado-ravaged school just six miles from our plant in Moore. In 2015, the Canadian County o-tech in El Reno was struck by the widest and longest tornado ever recorded. Initially rated an EF-5, the strongest possible, it was downgraded to EF-3, I think because of how well the precast concrete structure was saved. I saw steel light poles twisted off at their bases, and I have a picture of a precast concrete column pulled a few inches and a double tee lifted up, causing it to break in the middle from the underside of the deck to the strand and run horizontal for more than 10 feet. I am hopeful that we are helping to make schools safer. We have made progress in Oklahoma, but nothing like Kansas, Missouri, and Arkansas. Search for “safe room” at fema.gov and you will see what the masonry industry has done to keep us safe with precast concrete. Their walls are no longer hollow; the code has been updated. I hope we can say precast, prestressed concrete is now the preferred choice of material for aboveground buildings that can be called safe rooms for any wind/fire/earthquake events in the future.
Robert Shade is sales manager at Coreslab Structures in Oklahoma City.
Visit the digital version of Ascent for more from Robert Shade about how precast concrete protects structures during windstorms.
BUILD TO LAST. When you build with Spancrete precast, your structures will stand the test of time. That’s because we’ve been perfecting precast for more than 70 years. Since the beginning, we’ve focused on quality, service and innovation. As a result, our precast systems are faster to install, longer lasting, safer and more sustainable. From virtual design to installation, we’ll work with you to make legendary structures.
Today, Spancrete is building the modern classics. spancrete.com | 855-900-SPAN
ASCENT UPDATE
THE FUTURE OF ASCENT
WE WOULD LIKE TO POINT OUT SOME CHANGES TO ASCENT MAGAZINE, STARTING WITH THIS ISSUE.
We are moving Headline news section to our website and are no longer publishing it in the printed issue. We also have removed the lists of certified precast plants and erectors. This information is easily available by clicking on the Certified Plants tab on our homepage, pci.org. We also have reduced the number of printed copies we send in the mail. Each address will receive one printed issue. Finally, many print feature stories have online-only sidebars, which you can find in our new and expanded digital issue. We look forward to these changes and hope you will join us as Ascent magazine enters a new and exciting chapter. As always, feel free to send article ideas and company news to tbagsarian@pci.org.
CHAPTER EXECUTIVES
HOW T SCEN ASCENT STSC A E PR CAILA T N BU DSSFOR ENT CE S ON A G SOLUTI DELIVERIN R EDUCATION HIGHE THE PCI 2019 T
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PCI CENTRAL REGION— PHIL WIEDEMANN
phone: (937) 833-3900 email: phil@pci-central.org pci-central.org
PCI GULF SOUTH—DAN ECKENRODE phone: (228) 239-3409 email: pcigulfsouth1@att.net wpcigulfsouth.org
PCI OF ILLINOIS & WISCONSIN— MICHAEL A. JOHNSON Phone: (815) 404-4690 Email: mike.johnson@pci-iw.org pci-iw.org
PCI MIDWEST—MIKE JOHNSRUD, PE phone: (952) 806-9997 email: mike@pcimidwest.org pcimidwest.org
PCI MOUNTAIN STATES— JIM SCHNEIDER, LEED AP
phone: (303) 562-8685 email: jschneider@pcims.org pcims.org
PCI NORTHEAST— RITA L. SERADERIAN, PE, LEED AP phone: (888) 700-5670 email: rseraderian@pcine.org pcine.org
PCI WEST—RUTH A. LEHMANN, PE, PMP phone: (949) 420-3638 email: ruth@pciwest.org pciwest.org
PRECAST CONCRETE MANUFACTURERS' ASSOCIATION OF TEXAS (PCMA OF TEXAS)—CHRIS LECHNER phone: (210) 633-6743 email: lechner@pcmatexas.org pcmatexas.org
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CONTINUING EDUCATION OPPORTUNITIES
PCI Continuing Education PCI is a registered continuing education provider with the American Institute of Architects (AIA), and the National Council of Examiners of Engineers and Surveyors (NCEES). PCI also has registered programs with the International Code Council (ICC). PCI’s educational offerings include a variety of programs to fit your schedule and preferred learning environment, such as webinars, seminars, lunch-and-learns, and online education. To learn more, visit pci.org.
Distance Learning Opportunities > W E B I N A RS PCI webinars are presented live each month by industry experts on a variety of topics from design and construction to sustainability and more. All webinars are FREE, one-hour long, and presented twice during the webinar week, at noon Pacific (3:00 p.m. Eastern) and noon Eastern. Webinars provide an inexpensive way to stay up to date on new materials, products, concepts, and more while earning continuing education credits. Visit pci.org for the full webinar schedule and registration information. U P C O M I N G W E B I N A R TO P I C S I N C L U D E : August:
What you need to know about maintenance of precast parking structures.
Fall:
Working with FEMA in building precast concrete storm shelters.
Visit pci.org/PCI/Education/Webinars for dates and times.
> PCI ELEARNING CENTER The PCI eLearning Center is the first education management system dedicated to the precast concrete structures industry. This free 24-hour online resource provides an opportunity for architects and engineers to earn continuing education credits on demand. Each course includes a webinar presentation recording, reference materials, and a quiz.
In-Person Learning Opportunities > S E M I N A RS A N D WO R K S H O P S PCI and its regional affiliates offer seminars and workshops all over the United States on a variety of topics. Visit pci.org for up-to-date seminar listings, additional information, and registration.
U P C O M I N G S E M I N A RS A N D WO R K S H O P S : Quality Control Schools Level I-II RO S E M O N T, I L L I N O I S
August 28-30, 2019 E D M O N TO N , A L B E RTA , C A N A DA
September 17-19, 2019 O R L A N D O, F LO R I DA
October 21-23, 2019
Level III RO S E M O N T, I L L I N O I S
August 27-30, 2019 N AS H V I L L E , T E N N E S S E E
December 4-7, 2019
Visit pci.org/schools or pci.org/events for more information and to register. > L E V E L I Q UA L I TY C O N T R O L S C H O O L L I V E O N L I N E PCI offers training for quality control technicians to prepare individuals for PCI personnel certification examinations. Visit pci.org/onlineacademy for details. > LUNCH-AND-LEARNS PCI’s lunch-and-learn/box-lunch programs are a convenient way for architects, engineers, and design professionals to receive continuing education credit without leaving the office. Industry experts visit your location; provide lunch; and present on topics such as sustainability, institutional construction, parking structures, aesthetics, blast resistance, the basics of precast, and many more. Visit pci.org/LearnAtLunch for a list of lunch-and-learn offerings and to submit a program request.
PCI RESOURCES
PRECAST/PRESTRESSED CONCRETE
DESIGN RESOURCES PCI develops, maintains, and disseminates the Body of Knowledge for designing, fabricating, and constructing precast concrete structures and systems. It is from this Body of Knowledge that building codes, design guides, education, and certification programs are derived. Please visit pci.org/design_resources for all of these design resources and more.
Architectural Precast Concrete Color and Texture Selection Guide, 2nd Edition (CTG-10) The “Architectural Precast Concrete—Color and Texture Selection Guide” has been reprinted with 12 new color and texture pages, plus identification pages with mixture designs. This includes nine new color pages with two new colors per page, two pages of new formliners, and one page of new clay brick-faced precast. The numbers in the guide have not been changed, so that there is no confusion between the old and the new versions.
Architectural Precast Concrete, 3rd Edition (MNL-122) This fully revised edition includes new sections on sustainability, condensation control, and blast resistance. You’ll get extensive updates in the areas of color, texture, finishes, weather, tolerances, connections, and windows, along with detailed specifications to meet today’s construction needs. Includes full-color photographs and a bonus DVD.
Precast Prestressed Concrete Parking Structures: Recommended Practice for Design and Construction, 3rd Edition (MNL-129-15; e-pub) Decades of research have proven that precast, prestressed concrete is a cost effective, durable solution for parking structures. Over 140 pages present the latest concepts in design and construction, including 16 pages of full-color photography and many details and design examples. This is the most comprehensive publication of its kind.
Photos: ICP2017.
Designer's Notebooks – Free The PCI Designer’s Notebooks provide detailed, in-depth information on precast concrete relevant to specific design topics such as acoustics, mold, and sustainability.
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FEMA SHELTERS
PRECAST CONCRETE FEMA SHELTERS KEEP COMMUNITIES SAFE MULTIUSE PRECAST CONCRETE FACILITIES MUST WITHSTAND WIND SPEEDS UP TO 250 MPH AND FLYING DEBRIS, ALL WHILE SERVING THE COMMUNITY IN AN AESTHETICALLY PLEASING STRUCTURE BY MONICA SCHULTES
Designers in Tornado Alley, the region of the United States where tornadoes occur most frequently, rely on the Federal Emergency Management Agency (FEMA) P-361, Safe Rooms for Tornadoes and Hurricanes: Guidance for Community and Residential Safe Rooms, for current guidelines on planning, designing, and constructing safe rooms that provide near-absolute protection from a tornado. All safe rooms constructed with FEMA grant funds must adhere to their criteria to withstand the extreme winds and wind-borne debris.
JOPLIN MISSOURI PUBLIC LIBRARY Joplin’s new public library required that a community safe room be incorporated into the design of the new facility. A large meeting room built of precast concrete panels was located in the center of the building along the front façade as an anchor to the transparent wings on either side. A series of tall windows moving up and down across the face connect the precast concrete structure to the rest of the building. Photo: Gayle Babcock, Architectural Imageworks. • Sapp Design AssociatesArchitects PC, Springfield, Mo. • Prestressed Casting Co., Springfield, Mo. • R.E. Smith Construction, Joplin, Mo.
The 2018 International Building Code requires the construction of storm shelters be included when K-12 schools and first-responder facilities are constructed in areas inside the FEMA wind zone of 250 mph.
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NEOSHO HIGH SCHOOL CLASSROOM ADDITION, NEOSHO, MO. Photo: Gayle Babcock, Architectural Imageworks.
Getting Grants There are two types of grant programs that meet the requirements of FEMA P-361 and ICC-500, ICC/NSSA Standard for the Design and Construction of Storm Shelters. Funds can be obtained through FEMA’s Hazard Mitigation and Pre-Disaster Mitigation grant programs. The paperwork is daunting, however, and many school districts and communities need help with the complicated administration and reporting requirements. “Toth Associates has been helping Missouri school districts obtain FEMA funding grants for more than 10 years,” says Brian Orr, vice president of Toth Associates, Springfield, Mo. He acknowledges the documentation is voluminous and can take hundreds of hours to complete. Orr also shares that in addition to assisting with the grant process, they often handle structural design and grant management. They also administer the often-overlooked operations and maintenance phases of these facilities over the grant life span of 50 years.
Gimme Shelter That is where precast concrete is an attractive solution. “Given its weight and hardened properties, precast is inherently tornadoresistant, so meeting these code requirements is not that difficult,” says Dave Robertson Jr., vice president of sales for Prestressed Casting Co. in Springfield, Mo. They have built more than 125 tornado-resistant structures in Missouri, most of which include insulated precast concrete wall panels with a double-tee roof.
• Sapp Design Associates Architects PC, Springfield, Mo. • Prestressed Casting Co., Springfield, Mo. • Branco Enterprises Inc., Neosho, Mo.
At first safe rooms were small and rectangular with short spans. Many backed up to berms and typically served as a multipurpose room. “Now we are pushing the envelope with wall heights, doubletee spans, and finishes to maximize grant dollars while meeting FEMA loading,” explains Robertson. Safe rooms now double as gymnasiums, classroom buildings, performing arts centers, and community centers. In addition to the turnkey aspect of precast concrete, the finishes, insulation, and other integral components are included in the safe envelope costs. Field-laid finishes are not covered, which enables precast concrete solutions to maximize the grant-matching dollars, Robertson explains. Precast concrete solutions offer more architectural finishes while meeting all the FEMA requirements. “We are seeing even large classrooms several hundred feet long and two stories high using prestressed concrete,” says Orr. As this construction has become more common over the last few years, products such as doors and windows have become more affordable. “Larger openings are now available, and you can even achieve a storefront look to allow more natural light into the space,” says Orr.
Missouri Projects Many local school districts in Missouri have worked to add safe rooms to their schools since the destruction of the May 2011 tornado, which killed 161 people in Joplin and destroyed homes, businesses, churches, and school buildings. Nearby Neosho school district urgently needed classroom space to replace modular units. The result was a creative addition in the form of a FEMA safe room, one of five such structures being built in the district. With a student population of 1600, a standalone safe room would have been massive. “These large volume, dual use/multipurpose shelter spaces are becoming commonplace,” says Pam Haldiman, senior project manager at Sapp Design Architects in Springfield. They solve space needs for schools and communities, instead of a single-use shelter that sits empty and unused except in the case of emergency. The 14,000-ft2, two-story precast concrete design was challenging. “It met the school district needs for much-needed classrooms, a new face on the front of the building, and utilized their FEMA grant for a safe room at the same time,” explains Haldiman. Different embedded thin brick colors, reveals, and other finishes were used to create color and textural changes and maximized the
creativity of the precast concrete. FEMA grants only pay for the basic structure of the safe room, not for additional field-laid veneers or applied specialty finishes. With the use of FEMA P-361-tested window assemblies, more natural light can be incorporated into these safe rooms, creating light, airy spaces like the classroom addition at Neosho High School. Sapp Design Associates has been helping school districts obtain funding and designing FEMA safe rooms over the last 15 years. Many districts have opted to build safe rooms without federal funding, even before current code changes. In Haldiman’s opinion, it is typically not a huge difference to upgrade to hardened space, depending on the construction type. Precast concrete is often the most economical for larger volume projects, eliminating the need for bracing and scaffolding of reinforced masonry, and is less affected by weather, enclosing the structure quickly and reducing the length of construction time. The Joplin storm served as a catalyst for putting plans into motion to help prevent another devastating catastrophe in Neosho school district and many others throughout Missouri.
MONETT PERFORMING ARTS CENTER The Monett school district made a long-range commitment to provide safe rooms at all of its campuses. With the help of a FEMA grant, a new performing arts center at the high school doubles as a 13,000-ft2 community safe room. Photo: Gayle Babcock, Architectural Imageworks. • Sapp Design Associates Architects PC, Springfield, Mo. • Prestressed Casting Co., Springfield, Mo. • R.E. Smith Construction, Joplin, Mo.
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Wisconsin Project
CARL JUNCTION HIGH SCHOOL. INTERMEDIATE AND ELEMENTARY SCHOOL SAFE ROOMS. CARL JUNCTION, MO. The Carl Junction school district opted to build safe rooms on several campuses without FEMA funding. To save the time and expense of additional applied finishes, and to break up the higher volume of their precast concrete indoor practice facility/fieldhouse/safe room at the high school, thin brick and a recessed band and graphic were cast into the precast concrete panels. At Carl Junction’s K-1 facility, two colors of thin brick cast into the panels as well as a mixture of applied metal panels and painted sections of the precast concrete give the illusion of a large corner window and created a fun, bright exterior at the main entrance to the school. At the intermediate school, thin brick was also cast into the precast concrete with additional recessed banding and undulating heights on the brick as a base to motivational words, creating an inspirational graphic on the side of the safe room near the school entrance. Photos: Gayle Babcock, Architectural Imageworks. • Sapp Design Associates Architects PC, Springfield, Mo. • Prestressed Casting Co., Springfield, Mo. • Crossland Construction Company Inc., Springfield, Mo.
The City of Madison, Wis., delivered on their promise that safety is not determined by zip code. Mobile homes are particularly vulnerable to damage, and this shelter not only provides safety in a storm but also serves as a gathering place for residents of Highland Manor. To qualify for $1.2 million in FEMA grant funding, the building had to meet design criteria intended to provide a superior level of life safety protection against the extreme wind speeds and flying debris associated with tornadoes. Given the FEMA requirements, the predominant choice was precast concrete, recalls Hamid Noughani, principal at Assemblage Architects in Middleton, Wis. “What attracted us the most was the simplicity of precast design. Precast components are simplified with roof-to-wall and wall-to-foundation connections,” says Noughani. “By limiting the points of failure, the structure can be easily inspected over its lifetime. Once you choose the [precast] system, then you deal with the aesthetics, cost implications, and schedule, and you make sure those fall into place.” raSmith engineers in Madison worked closely with Spancrete in Waukesha, Wis., to develop innovative connection details to ensure that the precast concrete components function as an integrated system. A heavily reinforced cast-in-place topping slab was used on the hollow-core roof slabs to provide a structural diaphragm to help ensure that precast concrete beams, wall panels, and hollow-core slab created a continuous load path for lateral wind pressures as well as uplift. Bringing the project to life required the design and construction team members to learn and apply FEMA standards that provide for “near-absolute” protection. David Boldt, project engineer at raSmith, notes that currently, only a few designers have experience with these FEMA standards. He predicts that these requirements CARL JUNCTION SCHOOL will become more widely DISTRICT understood as time goes on. The Carl Junction school district opted to build safe rooms on several The “safe room” designation is sometimes confused with the campuses without FEMA funding. To save the time and expense of related term, “storm shelter.” Highland facility is considered additional applied finishes, and to break upManor’s the higher volume of their precast concrete practice facility/fieldhouse/safe at the to both, based on indoor the following conditions: buildingsroom designed high school, thin brick and a recessed band and graphic were cast into meet ICC-500 are classified as “storm shelters.” FEMA P-361 adds the precast concrete panels. more demanding requirements beyond ICC-500, and only those At Carl Junction’s K-1 facility, two colors of thin brick cast into the panels structures can be called “safe rooms.” as well as a mixture of applied metal panels and painted sections of the Working with FEMA for awindow utilitarian building. precast concrete give thedollars illusiononly of a allowed large corner and created a fun, bright exterior at the Assemblage main entranceArchitects to the school. To keep within budget, selected inexpensive windows and put storm overwas them a cost-saving solution. At the intermediate school,doors thin brick alsoas cast into the precast concrete additional recessed banding heights Because with there are a lot of children in and the undulating community, “We tried on brickthe as aspace, base toso motivational words, creating an to the excite colors were introduced to inspirational invigorate the graphic on the side of the safe room near the school entrance. building,” explains Noughani. “Precast concrete was cost-effective and allowed critical components to be fabricated off-site and shipped to the site for assembly. This allowed construction to proceed during a relatively harsh winter without delays,” recalls Boldt. He adds that continuous inspection of field welding for connections joining precast concrete components was essential to ensuring the finished structure could perform as promised.
Highland Manor Community Shelter and Safe Room Location: Madison, Wis. Designer: Assemblage Architects, Middleton, Wis. Owner: City of Madison, Madison, Wis. Engineer: raSmith, Madison, Wis. Contractor: Miron Construction, Madison, WI PCI-Certified Precast Concrete Producer: Spancrete, Waukesha, Wis. Photos: Assemblage Architects.
There are typically only 14 minutes to act after a warning siren sounds, which is not enough time for a custodian to arrive to open the door. The design team added a special device to automatically provide access when the National Weather Service issues a tornado warning. By working together with homeowners in the community, the City of Madison, and FEMA, the Highland Manor Community Safe Room project overcame significant design challenges to become what may be the largest freestanding safe room in Wisconsin. The building represents an innovative, cost-effective approach to preventing fatalities during severe weather events and serves as a model for future shelters and safe rooms.
Arkansas Projects Springhill Elementary is a new K-5 facility in Greenbrier, Ark. It is designed for up to 600 students and has a built-in FEMA shelter large enough for 1100 occupants. The building is broken into four separate wings based on function and security. The north wing contains the combination gym and shelter, which was designed and built to FEMA standards even without grant funding. Springhill Elementary features an artistic and colorful precast concrete exterior, as well as large colorful and clear windows on the street side. “The Greenbrier project features geometric shapes
MAYFLOWER ELEMENTARY GYM & SAFE ROOM, MAYFLOWER, ARK. Photos: (top) Jackson Brown Palculict Architects LLC; (bottom) Coreslab Structures. • Jackson Brown Palculict Architects LLC, Little Rock, Ark. • Moser Construction, Bryant, Ark. • Coreslab Structures (ARK) Inc., Conway, Ark.
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SPRINGHILL ELEMENTARY GYM & SAFE ROOM, GREENBRIER, ARK. Photos: Stiler and Henry Photography. • Jackson Brown Palculict Architects LLC, Little Rock, Ark. • Nabholz Construction Corporation, Conway, Ark. • Coreslab Structures (ARK) Inc., Conway, Ark.
painted in homage to the well-known work of art by Piet Mondrian,”’ describes Randy Palculict, vice president of Jackson Brown Palculict Architects in Little Rock, Ark. The reveals in the precast concrete panels were painted with photo luminescent paint. The glow-in-the-dark treatment will serve as way-finding to the shelter for the public inw case of power outage. Palculict considers the multiuse storm shelter a better option because it is too expensive to only use in bad weather. “The school and community get better use out of it and more bang for their buck,” Palculict explains. With the vibrant colors and finishes, the new gym is the antithesis of a gray bunker. In 2014, the small town of Mayflower, Ark., was hit by a tornado rated EF-4 on the Enhanced Fujita scale, which rates tornado intensity on a scale from 1 to 5. At the time, the community had only one storm shelter at the middle school. The construction of a standalone building at the elementary school campus has the capacity to fit the entire school population of 450 people inside. The school project received additional donations to supplement the FEMA grant money. An exposed aggregate finish was used on the
12-in. thick precast concrete insulated panels with a reveal pattern to break up the large walls and keep within the restrictive budget. “I have seen projects where it is clearly a storm shelter, but they have pushed the limits with what precast concrete can do,” says Palculict. In all these projects, precast concrete was key to building aesthetically pleasing, multiuse structures that keep residents safe during extreme weather events. ●
See the digital version of Ascent for a sidebar on how tornado alley is shifting east. What are the implications for precast concrete and construction?
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PROFILE
Precast concrete panels and double tees were chosen as the construction type for the tornado shelter at the West, Tex., high school/middle school due to the height and widths required of a regulation basketball court with bleachers. The span created by the double tees allow large open areas uninterrupted by columns or additional bracing. All photos: Huckabee.
MORE THAN JUST ARCHITECTURE
HUCKABEE BALANCES CRITICAL NEEDS OF ARCHITECTURE AND STRUCTURAL ENGINEERING TO DESIGN STATE-OF-THEART STORM SHELTERS REQUIRED IN K-12 SCHOOLS By Craig A. Shutt Huckabee has long been a leader in designing state-of-the-art K-12 school projects in Texas that adapt to evolving teaching curricula. That work includes providing a storm shelter in projects that meet specific codes and requirements, and incorporating these as functional space that fits a creative environment. Fortunately, vice president of engineering Benchmark Harris not only enjoys the challenge those requirements produces, he sees it as his mission to develop new designs to share with designers nationwide. The 2015 and 2018 editions of the International Building Code incorporated a requirement that newly constructed buildings and significant additions to existing schools in high-wind zones must include a storm shelter that complies with code requirements. As many communities in North Texas are located in these zones, administrators began looking to meet the requirements in a cost-effective way. Architects and engineers at Huckabee seized this opportunity. “At Huckabee, we have done a lot to promote effective storm-shelter designs,” Harris says. “There is a great deal of K-12 construction in Texas, and administrators need answers about where and how to protect students during a storm. As this need developed, we made it our goal to help administrators across the nation work with emergency planners when designing storm shelters.” That desire fit well with Huckabee’s philosophy of evolution and innovation. “Huckabee is something of a contemporary to the original Bell Telephone Laboratories, which had an attitude of investing money in ideas and had a tremendous success rate,” he says. “Our leadership invests money where we see potential for innovation. Some people find it strange that an architectural firm takes on some of these research projects, but we do much more than just architecture.”
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Tragedy Offered Catalyst Huckabee’s focus on storm shelters ratcheted up in 2013, after a massive fertilizer plant explosion in West, Tex., damaged hundreds of buildings, including three of the school district’s facilities. While some were renovated, the high school was demolished and rebuilt into a combined high school/middle school campus, complete with a precast concrete storm shelter. Opened in August 2016, the school features a regulation basketball court constructed with precast concrete panels and double tees, which offered the floor plan area required for a shelter while creating large, open areas uninterrupted by columns or additional bracing, making it easier to supervise the students. “The thickness of the precast concrete walls provides a fortress of security during a tornado event, and the smooth texture of the concrete walls creates an ideal surface for paint, graphics, and wall padding,” says Greg Gaskie, an architectural associate with Huckabee. This early work, along with the 2015 code changes, pushed these designs to the forefront at Huckabee. “I became a lightning rod for developing standards and processes that could result in the successful collaboration of various design disciplines on tornado shelters,” says Harris. The entire industry is moving forward, in conjunction with the National Storm Shelter Association (NSSA), Harris notes. “Storm shelters are a new concept for many school districts. Administrators aren’t sure what they need to do.” A key approach for Huckabee’s designers has been to take a programmed space and design it so that a multipurpose space, such as a gymnasium, also serves as the shelter. This is applicable where design wind speeds are 250 mph and associated with EF5-level tornadoes, the maximum rating on the Enhanced Fujita scale of tornado intensity, in the highest Tornado Alley-type zones. The design, which meets the needs of many Texas schools, features wind-pressure and impact-protective systems such as tested door assemblies.
Overcoming Myths Top: From the exterior, the brick and concrete masonry unit veneer at the West, Tex., high school/middle school tornado shelter proves that a safe and secure environment can be created while still allowing for an aesthetic façade. Bottom: The thickness of the shelter's precast concrete walls provides a “fortress” of security during a tornado event. The smooth texture creates an ideal surface for paint, graphics, and wall padding.
In meeting storm requirements, he stresses, it’s important to overcome myths that lead clients in the wrong direction. “It’s easy for administrators to see generic FEMA [Federal Emergency Management Agency] guidelines that were intended for use with older structures without tornado shelters, and not realize that those guidelines do not apply to a new structure with a tornado shelter.” Because of that guidance, schools will sometimes start by thinking they need several smaller spaces as the shelter. “It’s an understandable approach, but some emergency planners recommend having everyone in a large, open space so that students are more easily supervised. If the shelter is designed for the open geometry, it’s an acceptable place to protect students.” The larger gymnasium shelter space will typically have a higher cost per square foot than a classroom shelter, he notes. “However, the cost increase per occupant to provide the shelter is actually less for gymnasium shelters in our experience.” The actual usable space
Precast concrete at the Dr. Sarah K. Jandrucko Academy for Early Learners is designed to withstand 250-mph winds and airborne debris. The louvers installed within the walls are tornado-resistant while allowing air to be circulated through the shelter for the occupants.
“All things being equal, precast concrete offers the best costeffectiveness for these gymnasium shelter spaces in our experience.” is less per square foot for classroom spaces because there are desks, chairs and other equipment, requiring more overall square footage to meet the usable space-per-person requirement. “When all factors are included, it makes more sense to use a large space like a gymnasium.” To further enhance cost-effectiveness, Huckabee designs its storm shelters using precast concrete components, including beams, columns, double tees, and panels. “All things being equal, precast concrete offers the best cost-effectiveness for these gymnasium shelter spaces in our experience.” A space designed with precast concrete components can fit into any type of learning environment, he notes, providing every school with a protected, easily supervised space. In an elementary school, this design can be an activity room; in middle school projects, it often doubles as the gymnasium. For high schools, it is often designated as the practice gym or gyms, which do not have as much seating as a competition gymnasium. This consistent design aids users if the school system elects to make all tornado shelters be precast concrete gymnasium shelters, as students are more likely to know where to go for shelter no matter what school they’re in. “There’s a synergy that develops because the space is cost-effective, the appropriate size, and in a
recognizable location,” he says. “As kids move through the grades and schools, they recognize the shelter space and don’t have to be directed where to go.” These spaces provide the right boxy shape and size for a storm shelter, but it’s not necessarily that easy. “Some provisions are written in the standard as if the shelter is always a rectangular prism, and that’s not always true. We often have to adapt our standard design ideas to fit the individual school’s needs.” A recent example is the Dr. Sarah K. Jandrucko Academy for Early Learners in Mansfield, Tex. Huckabee worked with Bartlett Cocke General Contractors to create a 54,000-ft2, prekindergarten facility that resembles “a hands-on children’s museum with dedicated themes” carried into decor and interactive exhibits, according to the contractor. Four thematic pods branch into 16 classroom environments. The storm shelter was fit into this environment by designing it to serve as a multipurpose activity room, because there is no “gymnasium.” The precast concrete structural system, including panels and double tees, can withstand 250-mph winds and airborne debris. It also features storm louvers in the walls that resist the standardized 2 × 4 design tornado debris while allowing air to circulate.
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School Versus Shelter Inserting this type of highly structural element into a building’s architectural plan often leads to design challenges because the shelter’s needs are so different from those of a school. Harris is working to assist design professionals with these challenges through speaking engagements at conferences and participation with organizations, especially NSSA. The group, for which Harris serves as a vice president, provides educational resources and other support for designing storm shelters. “There is enormous interest from not only designers and structural engineers but also owners, contractors, emergency planners, and first responders.” They need as much guidance as they can find, he says. Many of the standards being applied to storm shelters were originally written for FEMA-funded safe rooms, which don’t necessarily have the same purpose or standards. “In some ways, it’s the wild, wild West out there,” he says. The code includes many gray areas that can be interpreted liberally or conservatively. “That doesn’t help anyone determine if they’ve achieved an effective solution. Designers don’t want to under-de-
“We’re very proactive with examining new concepts and products to incorporate into our plans.”
sign, but they also don’t want to over-design. Neither is an acceptable outcome in an owner’s eyes.” Fortunately, a standard of care is developing, and Harris is helping accomplish that in conjunction with NSSA. The group is creating white papers to post online to help define practices. “We have attended building code hearings and NSSA has attended other group conferences to be proactive, taking in comments and receiving input from many perspectives,” he says. “We hope that will result in significant changes that will register with code officials.”
Developing Standard of Care Harris also is working with several structural engineering firms as part of a group within the Structural Engineers Association of Texas. “SEAoT’s preliminary efforts have been well received and there has been good feedback from structural engineers around the country.” Some of these concepts are now being reviewed by NSSA’s Design Practices Committee to be forwarded for consideration by various code bodies. Some have already been considered and approved by IS-STM, which is the International Code Council committee that oversees ICC-500, the standard for tornado shelter design. Huckabee’s own concept has evolved as new ideas, techniques, and products have arisen. It’s now into its fourth generation of design, which is customized to each client’s needs. “The engineers work closely with the architectural side to create an attractive building that works better than the code requires,” he says.
Left: Precast concrete panels and double tees were designed and constructed at Dr. Sarah K. Jandrucko Academy for Early Learners in Mansfield, Tex. The design not only protects the occupants of the shelter during a severe storm event but also allows it to serve as a multipurpose room on a daily basis. Right: Precast concrete has become the construction type of choice for shelters that also need to maintain open floor space, such as gymnasiums and multipurpose rooms. As this shelter at the West Maine elementary school in Lancaster, Tex., shows, the concrete box is transformed into a space for sports and activities once paint and graphics are applied and gym equipment is installed.
“We think we’ve developed a best-practices approach that we can keep improving.” Among its concepts is the use of lower heights for parapets, which can catch windborne debris. One façade is typically designed without any parapet so water can flow to an area with less concern about ponding. The firm also specifies a multiple storm-louver baffling system to handle small windborne debris in addition to the standardized 2 × 4 design debris. “Our architects and structural engineers think holistically about the building, balancing standards for the shelter with those for the school functions and sincerely address both sides,” he says. Huckabee’s in-house structural group aids that process. “Many architectural firms sub out their engineering and give them a defined scope of work, which makes it harder for them to see the big picture and provide the same level of integration that we can offer by doing this together.” The challenges can be seen in such basic areas as reviewing shop drawings. Typically, a structural engineer wouldn’t review a door’s drawings. But when it must meet storm-shelter code requirements, those duties can change. “The review may require either or both, depending on the company’s processes.” (NSSA’s position is that the structural engineer should be involved with the required wind-pressure rating, and a future white paper will clarify recommended roles and responsibilities with submittals.) New products offer a unique challenge. Huckabee evaluates many on its own, providing feedback to vendors. “We’re very proactive with examining new concepts and products to incorporate into our plans,” he says. “We’ve developed a strong relationship
with vendors to explain what school districts need, because our clients benefit from those changes.” Product enhancements can be difficult to enact, he notes, because changes involve costs for vendors, and the certification process can be long and expensive. “They have to really be invested in providing products that offer the best level of protection possible and work with the certification bodies to get their products approved. Complex assemblies can be difficult to change.” To aid this, NSSA is working on an Impact-Protective System and Construction Assemblies database that identifies products/ assemblies that are successfully tested and offers guidance on how to apply the standards using various products/assemblies. As Huckabee’s design concepts evolve, so too does the company. It currently operates six offices, which have opened organically as clients developed in a region, spreading out from its Fort Worth base. “Growth in local interest is the primary reason we open a new office,” Harris says. As more schools are required to incorporate tornado shelters and as school designs evolve, so too will the designs for Huckabee’s shelters. “We’re here because of the students. They drive every aspect of our firm and they’re the reason we’ll continue to innovate.” ● See the digital issue of Ascent for sidebars on the benefits of Huckabee's cost-effective designs, Huckabee's continued growth, and resources offered by the National Storm Shelter Association.
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HURRICANE
SANDY RESILIENCY AND RENEWAL PROGRAM:
PRECAST CONCRETE PROTECTS CRITICAL INFRASTRUCTURE
AFTER THE PERFECT STORM: NEW NORMAL FOR STORM-RESISTANT BUILDING CONSTRUCTION FEATURES PRECAST CONCRETE BY MONICA SCHULTES
No one was prepared for a storm the magnitude of Superstorm Sandy in 2012. Sandy was exceptionally large, with hurricane-force winds 175 miles from the eye, and tropical-storm-force winds extending beyond 500 miles. With such wind velocity and range, more than 8.6 million people were without power, leaving more people in the dark than any other storm in history.
In addition to assessing the aftermath, the newly formed New York City Building Resiliency Task Force developed specific proposals to create “resilient” buildings: buildings that, in the face of hurricanes, heavy rains, heat waves, blackouts, blizzards, and flooding, will resist damage, protect occupants, and allow evacuated residents to return quickly to their homes.
The recommendations issued by the task force include a category entitled “Stronger Buildings.” The chapter on stronger buildings includes recommendations related to managing flooding, resisting wind, and advancing building systems in preparation for natural hazards. As a direct result, many such projects focus on relocating infrastructure systems from lower levels to elevations above the flood zone. A classic example is the work being completed at the New York City Housing Authority’s Redfern Houses development.
GOES Satallite Image of Hurricane Sandy Photo: NASA GOES Project.
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Left: The insulated precast concrete panels of the Redfern Houses provide a finished appearance as well as durable interior. The community/ childcare center features a distinctive façade with insulated precast concrete panels and hurricane-resistant glazing. Rendering: MDSzerbaty Associates Architecture.
PROJECT SPOTLIGHT REDFERN HOUSES
LOCATION: Queens, N.Y. Designer: MDSzerbaty Associates Architecture, New York, N.Y. Owner: New York City Housing Authority, New York, N.Y. Engineer: YAS Consulting Engineers, New York, N.Y. Contractor: Navillus Contracting, New York, N.Y. PCI-Certified Precast Concrete Producer: Coreslab Structures (CONN), Thomaston, Conn. (Redfern Houses) NPCA Precast Concrete Producer: Coastal Pipeline, Calverton, N.Y. (Bayside retaining wall) Precast Concrete Components: 14,021 ft2, 48 structural walls, 117 hollow-core pieces, 60 cladding panels, 9 copings (Redfern Houses), 5200 ft of perimeter floodwall (Bayside)
Right: Construction is under way at Redfern Houses where in the aftermath of Superstorm Sandy, it was necessary for the New York City Housing Authority to rebuild critical infrastructure systems in a rapid yet cost-effective manner. Photo: Coreslab Structures.
Redfern Houses, Far Rockaway, Queens, N.Y. During Sandy, apartments at Redfern Houses—a nine-building, 604unit housing development in Far Rockaway—were flooded and without power and heat for weeks. The New York City Housing Authority (NYCHA), as part of its Recovery and Resiliency Department, is completing upgrades to infrastructure and building a new community center and daycare facility to replace the one severely damaged. Five electrical power service buildings, a boiler plant, and a two-story, 14,295-ft2 community center are under construction. The latter includes the daycare center, offices, storage space on the ground floor, and community space on the second floor. The new electric service buildings are elevated above the NYC-codeprescribed design flood elevation to prevent future power loss from flood conditions. In addition, these structures house gas-driven standby emergency generators to provide full power capacity for the entire residential complex. A new boiler plant, also elevated above flood level, is being constructed on top of an existing coal bunker to replace the current boiler room, which was below grade and completely flooded. MDSzerbaty Associates Architecture (MDSA) in New York has been involved in five Sandy Resiliency Projects for NYCHA. “Developing resilient methods for each site, funded by FEMA [Federal Emergency Management Agency] grant dollars, has been challenging. Working with the updated FEMA guidelines, MDSA is relocating the electric service and other utilities into new structures at the Far Rockaway site,” says Michael D. Szerbaty, principal at MDSA. “Redfern Houses were inundated with water during the storm. We needed to raise up the critical infrastructure and buildings, including the community and childcare center to meet the 500-year flood elevation,” explains Szerbaty.
Hardened Building Envelope “MDSA has used precast concrete for decades and we turned to it for these structures, since a hardened envelope was desirable,” continues Szerbaty. “For these types of structures, a precast concrete building was simple and appropriate. It also minimized the number of trades on-site.” The insulated architectural panels provide a finished appearance as well as durable interior. The community/childcare center features a distinctive façade with insulated precast concrete panels and hurricane-resistant glazing. “The precast solution has enabled rebuilding the NYCHA critical systems in a rapid yet cost-effective manner,” says Aldo Rodhani, project manager with Coreslab Structures (CONN). “In addition to expedited construction time, selecting total–precast makes project coordination easier and reduces the risk of errors during construction,” he adds. The boiler plant and electric service buildings were enclosed in just a matter of days, allowing construction to progress. “Precast panels have been proven to be economically viable, and we don’t have to worry about waterproofing, installing insulation in the field, vapor barriers, and flashing—it is all in the insulated precast panel. It is as simple as you can get,” says Szerbaty. The light sandblast on the childcare center is offset by reveals and rustications in the large precast concrete walls to break up the scale and create shadow lines. “You use a precast insulated wall panel and many basic technical problems are solved without a lot of concern,” says Szerbaty. In addition, while the revised NYC energy codes are becoming more stringent, precast concrete insulated panels help meet or exceed those goals. “With insulated precast wall panels, we don’t have to worry,” he explains. “We now have a fully protected, elevated building that will serve as shelter should a similar weather event occur.”
At the Ocean Bay Apartments, a precast concrete perimeter floodwall, over 5200 ft in length, encircles the 32-acre site to prevent surface flood waters from entering above grade, and prevent subsurface water seepage below grade. The floodwalls are visually hidden through use of sloped berms. Photo: MDSzerbaty Associates Architecture.
Bayside Stem Wall at Ocean Bay Apartments, Far Rockaway, Queens, N.Y. MDSA directed another project in Far Rockaway with NYCHA’s Recovery and Resiliency Department. The 24 Bayside apartment buildings provide housing for over 6000 residents. The entire 32-acre site is now encircled with a below-grade precast concrete barrier. The floodwall design is about one mile in length below grade and was originally designed as a cast-in-place concrete wall, but the retaining walls were converted to precast concrete to facilitate the schedule and simplify on-site construction. The program provides flood protection following FEMA-prescribed requirements and includes electric service buildings similar to the Redfern project. The precast concrete perimeter floodwall surrounds the two city blocks to prevent surface flood waters from entering above grade and prevent subsurface water seepage below grade. The floodwalls are hidden beneath sloped berms and include flood gates for pedestrian and vehicular use.
Precast concrete is often a logistical challenge in the New York metro area due to narrow and crowded streets. These projects in the outer boroughs were better able to accommodate the crane and delivery of the precast concrete pieces. Whether above or below grade, precast concrete demonstrates it can be part of the Stronger Buildings initiative. These and other changes ensure New York will make people, property, and infrastructure more resilient to increasing hazards and vulnerabilities in the future. ●
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USRC
RESILIENCE IS THE NEW SUSTAINABILITY BY EVAN REIS For many years, the design and construction industry has equated the term sustainability with carbon footprint. When this is the primary metric by which sustainability is measured, it is difficult for concrete to compete, because it must play catchup both in technology and perception when compared to other materials. The concrete industry is missing an essential strategy where it is a natural leader compared to other materials. Carbon, or green design, is only one component of sustainability. The other is resilience.
The U.S. Resiliency Council awarded its first platinum rating to the City of Roseville, Calif., Office Building, constructed with total–precast concrete system. Photo: LPAS Architecture + Design.
Having the platinum rating signifies that the building will perform well after an earthquake and Roseville city services should have limited interruption, if any. Photo: LPAS Architecture + Design.
The USRC methodology takes advantage of state-of-the-art techniques to calculate life-cycle cost benefits and return on investment for resilient design.
The U.S. Resiliency Council (USRC) is committed to building public awareness of the performance of buildings in natural disasters and communicating the value of resilience-based design in protecting not only the lives, but the livelihoods of Americans. Both the social and the economic impacts that natural disasters cause are absolutely critical to defining a society, a business, or a family as sustainable. We must not only have a low impact on the environment, the environment must have a low impact on us.
Resilient Housing Stock The more the public demands better performance in their buildings, the more developers, cities, and businesses will take notice. In San Francisco, one of the top resilience goals is to have 95% of its population return within a year after a major earthquake. This doesn’t mean just having a 95% occupancy rate. San Francisco’s goal is to maintain the character of its neighborhoods; therefore, it wants 95% of the existing population to be able to return. The only way that will happen is if the housing stock is resilient enough to be economically repaired. If it takes two to three years to replace a building that has to be demolished and rebuilt, versus two to three months to repair a
The U.S. Resiliency Council platinum-award winning City of Roseville, Calif., Office Building. Photo: LPAS Architecture + Design.
building with only minor damage, it is far more likely in the latter case that the existing occupants will be able to return. The concrete industry must engage in similar education and advocacy if it is to build public demand for higher performing buildings. These high-performance goals typically cost only 1% to 3% more than buildings that meet the minimum code standards. Often, simply a change from one material to another can make a positive impact on performance with no added cost. Despite these arguments in favor, the U.S. Resiliency Council recognizes that inertia and other factors hold back decision makers. Switching to an unfamiliar structural system, trying a new construction technique, or having to defend even a small budget increase results in the typical questions, “Why take the risk? Why should I do that when no one is asking for it?� The USRC methodology takes advantage of state-of-the-art techniques to calculate life-cycle cost benefits and return on investment for resilient design, and is working to increase demand for better performing buildings by those who are buying, leasing, lending, and insuring them. In Tokyo, buildings that use seismic base isolation systems command 40% higher rents and resale values because the requirement is high for seismically resilient structures. There are even television and subway advertisements for base isolation. When is the last time you saw something like that on American TV? Popular demand is high because of the recent history of damaging earthquakes in Japan—and a strong public education program about the benefits of resilience-based design in protecting the social and economic fabric of the country.
Right: The U.S. Resiliency Council platform measures the safety, damage, and recovery of a structure. Images: U.S. Resiliency Council.
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THiN-Wall
or email douglas.gremel@owenscorning.com to request a USB drive full of additional information.
Photo: LPAS Architecture + Design. Logo: U.S. Resiliency Council.
Wind, Flood, Fire, and Blast This philosophy applies beyond earthquakes. The threefold principles of measuring safety, damage, and recovery of a structure extends across all natural and man-made disasters. The USRC’s current earthquake performance rating system will be joined by rating systems for wind, flood, fire, and blast. All of these hazards are particularly well suited to precast concrete construction and the inherent multihazard resilience it delivers. If the industry wants to build demand for better performing buildings using precast concrete, it should focus on its natural advantages and resilience to earthquake, wind, flood, and fire. Owners, tenants, lenders, insurers, and governments can relate to the safety of the buildings in which their residents, clients, and families live and work. They can relate to the preservation of a community’s economy and social fabric that can only be achieved if those buildings can be repaired and returned to functionality quickly after an event. There is always a need to crunch the numbers and show that an industry can be competitive on a first-cost basis with other industries. And we need desperately to reduce environmental impacts on our planet. But we must also consider the future social and economic resilience of our communities by building in ways that will be durable in the face of natural hazards. ● Evan Reis is the executive director and cofounder of the U.S. Resiliency Council.
See the digital version of Ascent for a sidebar about how one group is striving to improve Florida’s building codes.
MEXICO BEACH’S LONE SURVIVOR Sand Palace of Mexico Beach, Fla., made national news in the aftermath of Hurricane Michael. The image of one structure that remained standing in a field of devastation captured the attention of many. Owner Lebron Lackey of Tennessee shared his thoughts regarding the genesis of his vacation home. The goal was to create a house that would stay in the family for generations. “The survivability of the building in a major hurricane, you might call it the Big One, was our primary concern and the driver behind all of our decisions,” Lackey says. The structure used 12-in., 40-ft-long prestressed concrete piles that cantilever up from bearing. Precast concrete beams support insulated concrete form walls. The physician was prescient in his use of concrete and resilient construction. “For us, function always won out over form. Before Hurricane Michael, we would not have said that we had the prettiest house in Mexico Beach, but after it would seem we have the only house still standing,” says Lackey. — Monica Schultes
See the digital version of Ascent to watch a video of the home’s owners explaining how it survived Hurricane Michael.
The house in Mexico Beach, Fla., remained standing after Hurricane Michael. Owner Lebron Lackey credits concrete and resilient construction. Photos: Dr. Lebron Lackey.
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WEST COAST
CALIFORNIA UNIVERSITIES EMBRACE COOL STYLE As population and urbanization increase in California, more people are living and working in active seismic regions. The challenge is to help protect life and property of what will soon be 40 million people living in the state. The design of resilient buildings relies not only on sophisticated analysis but also advanced, reliable options in materials and structural systems like precast concrete technology.
California State University at Sacramento and San Francisco State University used precast concrete in different forms to create beautiful, resilient structures that can withstand major events such as earthquakes, floods, hurricanes, heat waves, wildfires, and mudslides.
THE SUBSTANCE OF STYLE IN CALIFORNIA ADVANCES USING PRECAST CONCRETE FOR HIGH-SEISMIC REGIONS BY MONICA SCHULTES
Facing page: Wellness Center features glass-fiberreinforced concrete panels that are crisp and modern with vertical scalloping texture along the façade. Photo: Jeremy Bittermann. Left: Parking Structure 5, California State University– Sacramento Photo: Kyle Jeffers, courtesy of Dreyfuss + Blackford Architecture.
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Parking Structure 5, California State University, Sacramento The new six-level parking structure at the entrance to California State University in Sacramento is no ordinary 1750-space garage. Using the collaborative design-build delivery method, the project team succeeded in keeping the focus on the needs, comfort, and experience of the user. “We focus on the people aspect of the structure, not a garage that only stores cars,” explains Jason A. Silva, partner/design principal with Dreyfuss + Blackford Architecture in Sacramento. Collaborative design-build is a process that Dreyfuss + Blackford has championed, especially with universities that need to deliver big projects quickly. The process, which combines the best of construction management at risk and traditional design-build, allows the owner to play an important role in the early stages of design while guaranteeing maximum price at the schematic design phase. The relationship works well for precast concrete, given the front-loaded design. “Working with Clark Pacific, our whole approach was how to make the best garage using precast concrete. We were able to create an open and airy structure that was only achievable from the beginning, rather than redesigning for precast,” says Silva.
See the Forest and the Trees Above: Green metal leaves generate shadow patterns and the perception of movement, paying homage to the campus arboretum. Above right: The exposed stems of the double tees emulate dentils and the articulation draws the eye. Photos: Kyle Jeffers, courtesy of Dreyfuss+ Blackford Architecture.
Aesthetics were of paramount importance to the university because the parking structure is a gateway to campus and nestled into their arboretum. To play off the plethora of trees on university grounds, the design concept features green metal fins in a random pattern to mimic leaves. A custom formliner was selected to emulate the grain of tree bark.
PROJECT SPOTLIGHT
PARKING STRUCTURE 5, CALIFORNIA STATE UNIVERSITY–SACRAMENTO LOCATION: Sacramento, Calif.
Project Type: Parking structure Size: 515,015 ft2 Designer: Dreyfuss + Blackford Architecture, Sacramento, Calif. Owner: California State University, Sacramento, Calif. Structural Engineer: Buehler & Buehler Structural Engineers, Sacramento, Calif. Contractor: Clark Pacific, West Sacramento, Calif. “Ultimately we wanted to maximize the randomness as well as the efficiency and flexibility of the design features. The woodland elements were also conveyed through the unique formliner module that spread evenly over column and bay spacing,” says Silva. “The result gives an illusion of scalloping. The form relief on the columns stops to break up the lower half of the building and to maximize the efficiency of a single length of master formliner.” The bay spacing was adjusted on the hybrid moment frame (HMF) lateral system to achieve uniform 24-ft column spacing consistently throughout. A typical parking structure entrance opening forced an irregular column spacing in the transverse direction. “The innovative solution here was to create a rhythm of columns. Take that 60-ft module and place the moment frame columns at 20 ft on center,” says Farid Ibrahim, director of preconstruction services for Clark Pacific in West Sacramento. They resolved the ingress/egress issue by offsetting the entry to the outside and realigning the drive aisles after entering the structure. The regular column spacing made the HMF even more efficient and maximized the parking layout.
Off Campus The university wanted to minimize disruption and to bring the structure online as quickly as possible. At the time, there were five concurrent projects, three of which eliminated surface lots, making parking a premium. “We delivered the garage in nine and a half months from breaking ground to commissioning,” says Ibrahim. “We calculated that 5700 worker days were moved off-site in comparison to a cast-in-place concrete alternate. The urban campus would have been highly impacted by those additional trades driving and parking each day. Construction and education don’t mix well. The idea was to get it done as quickly as possible with the
PCI-Certified Precast Concrete Producer: Clark Pacific, West Sacramento, Calif. Precast Concrete Components: 6089 pieces, including double tees, spandrel panels, columns, beams, stair and landing units
least impact to the university. Offsetting trades to the manufacturing site helped achieve that goal.” The entire campus was impressed at how fast the structure was erected with so little disruption. “Their jaws dropped when they saw the garage appear in a matter of weeks,” says Silva. In keeping with university focus on sustainability and energy efficiency, ParkSmart goals were targeted. ParkSmart is the equivalent of LEED certification for parking structures. The project team also is pursuing a U.S. Resiliency Council (USRC) rating. The target gold USRC certification will demonstrate that the parking structure isn’t just a beautiful structure that was quickly built, but one that can withstand a major earthquake. In addition to meeting code requirements, the HMF provides enhanced structural performance during an earthquake for the safety of the three occupant types: faculty, students, and employees. It was of value to the university that this structure was designed with seismic performance in mind. The design team gave a lot of thought and consideration to every detail of this parking structure. The selection of HMF provides peak performance ideal in high-seismic regions.
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San Francisco State University Mashouf Wellness Center The striking new building at San Francisco State University is the new hub of the urban campus community for those who want to exercise as well as socialize. The 118,700-ft2 facility features fitness and weight areas, courts, three studios, a sauna, two pools, and a large multiuse space that can host team activities as well as student events. Located on a prominent intersection off Lake Merced Boulevard, the Mashouf Wellness Center (MWC) serves as a signature facility and campus gateway. The shape of the building reflects the triangular site, and the three main modules (natatorium, gym, and courts) of the structure reach out in different directions.
Wellness by Design The façade features glass-fiber-reinforced concrete (GFRC) panels that are crisp and modern, reflecting both the university culture and the diverse activity within. “We designed the GFRC panels to mimic a monolithic shroud covering. As you walk closer, you can read the vertical random scalloping texture along the façade. The vertical patterning of the GFRC creates shadows to hide the vertical panel joints,” describes Edward Kim, project manager and associate at WRNS Studio in San Francisco. “GFRC has a very plastic nature and enables us to create crisp edges and shadows,” adds Kim. “We performed sun studies to observe how the shadow lines move across the façade of the Wellness Center.”
Three-Dimensional Modeling Promotes Precast Concrete Creativity “In recent years 3-D modeling has become common and the process of conveying design ideas to precasters more streamlined,” explains Mark Hildebrand, president and chief engineer at Willis Construction Co. in San Juan Bautista, Calif. “Through CNC [computer numerical
control] technology we can create molds directly from computer models. GFRC panels are an attractive solution because it can manage elaborate shapes.” The MWC features panels that are 12 ft wide and up to 30 ft tall. The panels seem to float and bear only on the second level. Hildebrand explains the panels had to handle out-of-plane bending for wind loads. GFRC frames are more flexible and can handle the rotation and movement of a seismic event. “Because the interiors are so wide open inside there is not a lot of floor weight, so the whole structure was not very heavy and fit well with GFRC,” Hildebrand explains. GFRC panels are widely used in high-seismic areas, where their light weight and flexible frames enable the panels to accommodate large seismic motions. California Building Standards Code seismic requirements have grown more stringent and the panels on the MWC have to accommodate 4.8 in. of drift, capitalizing on the flexibility of the GFRC system.
Long-Term Well-Being The university wanted a long-lasting building and precast concrete is well established for its durability, which is often not considered with sustainability or resiliency goals. San Francisco State University has limited funding for construction and operations. “GFRC is very durable and low maintenance, and able to meet their goal of 50-year life. In this construction market where time is very expensive, it also makes sense to fabricate offsite,” says Kim. Given its capabilities for large-panel configuration, as well as the ability to accommodate large drifts in seismic events, the conditions in California are ripe for GFRC. “When we first started using GFRC, our designs were very two dimensional,” recalls Kim. “With evolving CNC technology and complex 3-D modeling, we are seeing more creativity expressed through GFRC and precast.” ●
See the digital issue of Ascent for a sidebar about how designers went to great lengths to provide natural light and ventilation for the California State University parking structure.
PROJECT SPOTLIGHT
SAN FRANCISCO STATE UNIVERSITY MASHOUF WELLNESS CENTER LOCATION: San Francisco, Calif.
Designer: WRNS Studio, San Francisco, Calif. Owner: San Francisco State University, San Francisco, Calif. Engineer: Forell/Elsesser Engineers, San Francisco, Calif. Contractor: CW Driver Builders, Pasadena, Calif. Facing page : The Mashouf Wellness Center features glass-fiberreinforced concrete panels that are crisp and modern with vertical scalloping texture along the faรงade. Above: The new facility at San Francisco State University includes a two-court gym, multiactivity court gym, elevated jogging track, weight and fitness space, natatorium with lap and recreation pools, climbing wall, racquetball courts, multipurpose/group fitness studios, and locker rooms, storage, and support space. Photos: Jeremy Bittermann.
PCI-Certified Precast Concrete Producer: Willis Construction, San Juan Bautista, Calif. Precast Concrete Components: GFRC panels, vertical fluting form shape, light sandblasted finish; total of 33,600 ft2, 131 individual panels
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U.S. ARMY
ARMY ADVANCES WITH PRECAST CONCRETE BY MONICA SCHULTES
PRECAST CONCRETE BARRACKS KEEP CYBERSECURITY SOLDIERS AT FORT GORDON SECURE
The innovative use of precast concrete met the building’s demanding design requirements while simultaneously featuring architectural exterior finishes. The structure was designed to resist the concussive force from explosion and to not progressively collapse if one of the pieces was damaged. Above: Precast concrete insulated wall panels feature two different types of thin set brick, a split-face concrete masonry unit formliner, and a replicated stucco finish. Photo: Caddell Construction
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Advanced Individual Training Barracks Phase II, Fort Gordon, Augusta, Ga. U.S. Army Base Fort Gordon in Augusta, Ga., is transforming into the premier instructional campus for cyberwarfare training. The construction of a new five-level housing structure used unique precast concrete elements to provide an open floor plan, expedited schedule, and reduced cost. “Precast concrete was a good fit for the barracks project to meet blast requirements and progressive collapse,” says Hassan Anvari, chief operating officer for EDT Constructors/Engineering Design Technologies in Marietta, Ga. “It significantly expedited the time required to construct the building.”
Concussive Forces
Creative Application of Bulb Tees
Meeting the blast requirement was very challenging, requiring detailed analysis and innovative methods. “The majority of detailing was atypical for precast construction and required creative methods to ensure overall building resistance to progressive collapse,” recalls Anvari. He explains that the original design was based on three spans of hollow-core slabs. However, this configuration would not allow the use of tie-force method. The only viable option was to use the alternate path method for progressive-collapse-resistant design. Using precast concrete bulb tees made it possible to span the building with one precast concrete member. To comply with the design requirements, complicated detailing was necessary to enable the structure to span the “lost” structural member and prevent a progressive collapse. The standard double tee was not adequate, due to limitations to the maximum allowable depth.
“The bulb tees also enabled a wide-open floor plan, which allowed us to remove interior columns and beams. The alternate system eliminated interior framing, foundations, and greatly reduced the number of precast components required, which saves time and money while also providing a more versatile structure for the barracks,” says Matt Goodwin, project manager at Tindall Corporation in Conley, Ga. “The bulb tees can withstand higher loads on longer spans versus traditional double tees.” The open floor plan was reflected on each floor of the barracks. A heavily reinforced topping slab was required on the bulb tees to accommodate the progressive collapse requirements. Additionally, there was an increase in the number and size of the connections throughout the precast concrete to accommodate the extra forces to withstand the concussive blast resistance.
“To comply with the design requirements, complicated detailing was necessary to enable the structure to span the “lost” structural member and prevent a progressive collapse.” Left: The 200,000 ft2 barracks used unique precast concrete elements to provide a more flexible and open floor plan and to reduce the number of pieces required to complete the project, further expediting the schedule and reducing the cost. Photo: Caddell Construction.
Reduced Life Cycle Costs
The innovative use of prestressed bulb tees in the barracks enabled the design team to meet the progressive collapse and blast design requirements. Using the bulb tee eliminated the need for interior columns and beams, and allowed the barracks to have an open floor plan. Photo: Tindall Corp.
In addition to blast and progressive collapse, another important feature was fire resistance. The use of precast concrete eliminated the need for fireproofing and the associated process, which is an intricate, intrusive, and costly operation. The Army Corps of Engineers (ACOE) values reduced life-cycle cost, especially through thermal efficiency in their buildings. “Use of 14-inch insulated precast wall panels allowed us to exceed R-21 insulation and provide a continuous thermal envelope with no thermal bridge,” says Anvari. Sound attenuation between rooms was also important to the ACOE for their trainees to avoid hearing noise in adjacent rooms. The ability to deflect or absorb sound also makes precast concrete a smart acoustic material. Some of the challenges the ACOE faced were dealing with multiple contractors within one construction zone and construction laydown areas that impacted training. Precast concrete components were cast off-site at Tindall Corporation’s production facility, minimizing the impact on Fort Gordon and avoiding encroachment on restricted laydown areas. With schedule such a critical factor, using precast concrete panels with inlaid brick and articulated multicolor finishes eliminated the need for masonry and other subcontractors. This also reduced possible additional construction hazards, such as extensive scaffolding and material handling for brick veneer construction.
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PROJECT SPOTLIGHT
ADVANCED INDIVIDUAL TRAINING BARRACKS PHASE II, FORT GORDON LOCATION: Augusta, Ga. Designer: U.S. Army Corps of Engineers, Savannah District, Ga. Owner: U.S. Army Corps of Engineers, Savannah District Engineer: Engineering Design Technologies, Marietta, Ga. Contractor: Caddell Construction, Montgomery, Ala. PCI-Certified Precast Concrete Producer: Tindall Corp, Conley, Ga. PCI-Certified Precast Concrete Erector: Bass Precast Erecting, Cleveland, Ga. Precast Concrete Components: 300,000 ft2 or 758 pieces, including 270 bulb tees, 268 14-in. insulated wall panels, 84 12-in. insulated wall panels, 60 12-in. shear walls, 51 8-in. wall panels, and 25 flat slabs
The precast concrete structure was designed to withstand progressive collapse and blast requirements while also meeting long-term thermal performance metrics and blending in with surrounding military campus. Photo: Caddell Construction.
The barracks are flanked by smaller precast concrete support structures, one building for lawn care and maintenance and the other for a geothermal steam system. To match the adjacent structures, the ACOE worked closely with Tindall to develop multiple custom concretes designed to replicate the stucco finish, grouted masonry, and brick joints on the existing barracks. In conjunction with two types of thin set brick, a split-face concrete masonry unit formliner, and plant-applied projecting windowsills, the exterior precast concrete panels blended seamlessly into the surrounding infrastructure.
While the housing structure was not required to be 75-year life building, the intent was to create a durable structure in a timely fashion, which would not have been achieved with anything other than precast concrete. “To comply with progressive collapse proved both challenging and complicated and required in-depth calculations and elaborate detailing to achieve mandated progressive collapse requirements,” recalls Anvari. Ultimately, Fort Gordon is slated to become an operational installation where U.S. soldiers will train and fight through cyber, signal, and military intelligence and reside in an equally secure housing facility. ●
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TECHNOLOGY
PCI FIRE STANDARD ADDED TO IBC 2021
HOW A REFERENCE INCLUSION OF A FIRE-RESISTANCE STANDARD IN THE BUILDING CODE WILL IMPACT DESIGNERS, ENGINEERS, AND CONTRACTORS BY CRAIG SHUTT The International Code Council (ICC) has accepted PCI’s consensus-developed fire standard, PCI 124, Specification for Fire Resistance of Precast/Prestressed Concrete, into the 2021 International Building Code (IBC) as an approved basis for determining fire resistance of precast and precast, prestressed concrete assemblies. The reference inclusion will simplify the process for the design and construction team and allow smoother inspections of precast concrete structures.
The key changes to the 2018 IBC update the reference from the 2011 MNL 124 manual to the new 2018 PCI 124 standard and expand its application beyond slab cover in section 722.2.3.1 to include calculated fire resistance of all precast and precast, prestressed concrete assemblies. The changes mean that fire resistance for precast concrete can be presented as code-based calculation methods based on the 2021 IBC. Designs based on the ICC-ES Evaluation Report, ESR-1997, will no longer be needed. (For other changes, see online sidebar.) “This is a big step for PCI and should please designers and engineers,” says Jason Krohn, vice president of engineering at S.K. Ghosh Associates LLC in Palatine, Ill., and PCI’s former managing director of technical activities. “It takes the manual—which was being used to a great extent already—and turns it into a code-referenced standard that can be used for all precast concrete assemblies.” Previously, the code only recognized manual-based fire resistance of precast concrete floor slabs, with other precast/prestressed assemblies only referenced in the manual, explains Steve Skalko, an independent consulting engineer on fire protection who works with PCI committees on code issues related to fire safety. “The manual made recommendations, but the wording wasn’t written in mandatory language. That gave building officials/inspectors too little direction with regards to enforceable language,” Skalko explains. “There were too many ‘mays’ and not enough ‘shalls.’ As a former code official, I understood the confusion that this could create if a designer took another approach.” In some cases, designers would look to other sources rather than use the provisions in the manual that weren’t codified. “This new approach makes PCI 124’s language a one-stop shop for designers looking to calculate fire resistance of any precast concrete assembly,” Krohn says. The 2018 version of the PCI 124 standard, Specification for Fire Resistance of Precast/ Prestressed Concrete, has been accepted into the 2021 International Building Code for all precast concrete assemblies. It is now available for purchase from PCI. Image: PCI.
“This new approach makes PCI 124’s language a one-stop shop for designers looking to calculate fire resistance for any precast concrete assembly.” That’s especially helpful on the West Coast, he notes, where ESR-1997 was referenced frequently. On a project-by-project basis, the designer or precast concrete producer was required to seek approval from the building official by presenting a copy of the evaluation report as evidence. Now, the ICC-ES evaluation report isn’t needed, as the PCI 124 is incorporated into the building code as a referenced standard. Much of the previous language included in MNL 124 has been incorporated into the commentary section of PCI 124 to ensure that the useful explanations are still available to put the standard into context.
Hollow-core’s inorganic composition and ability to cast off-site as other work progresses can aid fire resistance while speeding up the construction schedule. Photos: Spancrete.
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Manual Used for Decades In practice, the MNL 124 manual has been used by many designers for decades, Skalko adds, without the benefit of mandatory language or code inclusion. The manual was first issued in 1977, then updated in 1989 and 2011 as new techniques and processes were developed. The recommended design procedures in those editions were based on fire-test data and reports that dated from the 1960s, he says. The 2000 IBC referenced the procedures for precast concrete slabs in the manual as being acceptable but did not include the remaining procedures for other precast concrete elements directly. “As the industry matured, more information and tests became available that expanded our knowledge and how the manual could adapt to adjust to designs of other structural materials and to fit with the ways designers were using precast concrete in buildings,� Skalko explains. One key step in getting the manual accepted into the code came in 2014, with the designation of PCI as an American National Standards Institute (ANSI) Accredited Standards Developer. PCI members deemed fire resistance significant enough to the industry to focus right away on developing a standard through an ANSI consensus process suitable for adoption by reference in the building code.
The 2021 International Building Code will work as a one-stop shop for providing appropriate fire resistance for precast/prestressed concrete framing systems of all types. Photos: Spancrete.
All types of precast/prestressed concrete components, including wall panels and double tees, are covered in the PCI 124 manual that will be part of the 2021 IBC. Photo: Spancrete.
“PCI 124 has been accepted as a consensus standard, and designers can build to its requirements subject to approval of the code official.” The standard and required updates were developed following the procedures required by the PCI Group Operations Manual. The process involved generating and balloting suggestions from the PCI Fire Committee, which were reviewed and commented on by PCI’s Technical Activities Council (TAC). This was followed by making needed changes to the document, which were balloted again by PCI’s Fire Committee and accepted by TAC. The document then was submitted to PCI’s Standards Committee for additional review and balloting. A public-review period was provided, with public comments resolved in the language through the Standards Committee. This committee consists of a balance of interested parties including consumers, producers, and general interest individuals who may not be PCI members. Upon completion of the standards development process, PCI 124 was ready for adoption into the 2021 edition of the IBC. That adoption process, which occurred in 2018, was also open to the public for comment. No comments were offered, so the adoption process was completed.
Standard Available Now PCI 124 is available for purchase and can be used directly by any designers or engineers, knowing that it will be referenced in a future building code, Skalko stresses. “IBC 2021 is still finishing its development cycle, so it is not likely to be adopted into state and city codes for several years. But PCI 124 has been accepted as a consensus standard, and designers can build to its requirements subject to approval of the code official. Many already use it in any event and can readily reference it ahead of codification.” Skalko stresses that as an easy adoption for designers. “We think it represents the latest thinking and is complete enough to encourage designers to learn it and use it,” he says. “It’s very much accepted as the standard and will soon be published as an alternative to the prescriptive provisions now in the code.” ● See the digital version of Ascent for a sidebar about other code changes that will impact precast concrete design.
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UNIVERSITY PROFILE
TULANE PRECAST STUDIO TACKLES WATER MANAGEMENT FOUNDATION PROGRAMS
BY MARTY MCINTYRE, PCI FOUNDATION The PCI Foundation provides schools of architecture, engineering, and construction management an opportunity to use precast concrete design and construction as a springboard to educational topics that not only address the needs of the students in attaining their goals, but also will expand general knowledge about the precast concrete industry. At Tulane University in New Orleans, La., resilience is a key topic in students’ education through a studio titled, “Resilience Reinforced: Architectural Precast Concrete Systems Addressing the Regional Water Infrastructure Challenges.”
Tulane professors took a unique approach to tackle a problem that may seem specific to New Orleans today, but will likely become an issue all over the United States. In 2010, 123 million people, or 39% of the nation’s population, lived in counties directly on the coastline. This is expected to increase by 8% from 2010 to 2020, according to the National Coastal Population Report. So, when professors Kentaro Tsubaki and Charles Jones looked for an issue to tackle using precast concrete that would not only use the material to its best advantage but also be socially impactful, they zeroed in on water management in public spaces. A primary goal was to understand the concerns and constraints specific to urban water infrastructure projects and to identify worthy opportunities for full-scale mock-ups and testing in collaboration with precast concrete industry partners in future studios. The professors built their expertise step by step through multiple workshops with local experts, professionals, and industry partners. Top: Students work in teams to understand the water issues that confront Lafitte Greenway Park for which they are seeking to design flood solutions at the precast studio at Tulane University. Bottom: An important part of the precast studio at Tulane is students getting a plant tour with Tindall Precast. Students often note that once they tour a plant they finally begin to understand the scale and modularity that precast concrete can bring to a project. All photos: Tulane University.
Team Identifies Opportunities “The first semester was really about scoping and identifying specific opportunities that we can really dig into,” says Tsubaki. “It happened in two scales. The first, on a smaller scale, tackled the design of a sidewalk paving and rain garden. That primarily was led by Charles' digital fabrication seminar, and then merged into the studio. All of the students have to take the seminar and the studio. On the macro scale, we looked at the design of a linear park.” The program includes 10 students—primarily undergraduate, fourth-, and fifth-year students—and one graduate student. Two of the students continued their work from the studio as an independent study during the spring of 2019. Graduate research fellows also support the program. The program is intended to develop and deliver infrastructure projects that focus on the relationship between precast concrete systems, architecture, infrastructure, and the most abundant, and life-affirming, yet destructive, resource: water. The professors used the greater New Orleans urban water management plan as the framework, partly because a lot of basic research had already been completed, allowing the students and professors to develop the projects in more detail. The studio and the corequisite seminar examined the potential of precast concrete systems and advanced fabrication technology to address the regional water infrastructure challenges at two distinct urban scales: • Street scale: design of a hypothetical precast concrete sidewalk paving and rain-garden system to address water management issues • Neighborhood scale: design of a linear park (portion of Lafitte Greenway in New Orleans) to address the complex water management challenges with precast concrete components The paving and rain garden system design introduced students to considering urban water management infrastructure at a human scale, and introduced computer-numeric control milling technology in fabricating formwork for the paving system. The linear-park design introduced students to the use of large-scale precast concrete components to address complex urban water management challenges.
Linear Lafitte Greenway Park The team settled on Lafitte Greenway, a linear park connecting the French Quarter and Bayou St. John. Originally a shipping canal, it was later filled and turned into a railroad right-of-way, which has been abandoned since the middle of the 20th century. It was recently resurrected as a linear park, offering multiple design opportunities for pedestrian bridges, permeable paving systems, and retention walls. Students considered solutions to reduce frequent flooding in the neighborhood. The goal was to use the park for retention, while continuing to use it as a public space. They were required to look at the overall site and consider how the park might be composed of a terraced system, such as an amphitheater, to be productive as an event space and hold water when necessary.
Students watch as Ray Clark of U.S. Formliner prepares materials for them to create their own formliners.
“We cast a wide net, just looking at anything and everything that was precast,” says Jones. Bridges, foundations, shorelines, or erosion control systems were also vital parts of this research.
Local Industry Plays Big Role The teamwork in this project was slightly different than in some other PCI Foundation programs. Of course, local precast concrete producers were involved, but because Tulane does not have an engineering program, they looked to professionals from civil and structural engineering, landscape architects, planners, and others familiar with this work. Work on this project will continue over several years, allowing new solutions and research to develop through the precast concrete curriculum provided by the professors at Tulane and their local industry partners. The professors, with the help of their graduate research fellows, are currently analyzing each student project. The outcome serves as a catalogue of design approaches to address the complex water management challenges at these scales. The architectural and infrastructural solutions developed through the studio are nationally relevant, as the water-related issues are not unique to this region. The professors look forward to designing, constructing, and demonstrating an effective, aesthetically robust, and lowmaintenance precast concrete sidewalk paving and rain garden system though their design-build initiatives with students in the near future. ●
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COMPANY PROFILE ADVERTORIAL
PRECAST PROVIDES NATURAL DISASTER RESISTANCE
In response to the high seismic demand, the initial shear wall design called for the use of CIP concrete. Using emulative design practices, over 5000 grouted rebar splices, and wet joints for connections, the wall was converted to precast concrete. Because of the weight of the panels, a voided precast panel system with prestressed super columns was used. EnCon Utah’s precast scope included 23 single-piece columns and 300 panels. The auditorium shear wall is the first wall of this magnitude, and with this innovative design, to be constructed in this region. The auditorium’s interior is designed with upper and lower seating bowls, and precast prestressed risers are built in single and double riser sections on steel raker beams and house seating for 15,000 attendees. The walls were cast in a vertical battery mold to prevent movement of the voids and give form finish to both sides. Casting integral openings into the panels allowed for a single-unit design to reduce the number of pieces needed. Fewer walls decreased casting and crane time for a more efficient structure. An extensive bracing system was designed to support the wall until the wet joints were completed and reached the required strength. Cables were used to restrain all in-plane forces on the wall during construction. Once the columns were erected and braced, installation of the 16-inch-thick precast voided wall system began. Construction of this entire precast system was completed in ten weeks, saving eight months when compared to the original castin-place construction schedule. The precast solution solved a great number of construction and site logistics problems, and proved that this construction method is not only possible, but preferable.
NOT ONLY CAN PRECAST MEET THE CONSTRUCTION INDUSTRY’S DEMANDS FOR SPEED TO SITE, COST EFFECTIVE PROJECT SOLUTIONS, AND REDUCED FIELD LABOR, IT CAN PROVIDE CREATIVE AND INNOVATIVE BUILDING SOLUTIONS FOR NATURAL DISASTERS WHILE PROVIDING PROJECT DURABILITY AND RESILIENCY Whether originally designed in precast concrete, or a conversion from steel or cast- in-place (CIP) concrete to precast concrete, precast sets the role for fast and efficient project design and construction. Structures utilizing lateral systems with special detailing and shear walls are generally designed as CIP. Emulating a CIP seismic force resisting system like this can be done using precast components, while achieving the same results and meeting IBC and FEMA building code requirements in these project types. Precast concrete solutions and precast conversion strategies and can be designed for large and unique structures. Precast concrete can easily incorporate prestressed and post-tensioned pre-fabricated components that will enhance catastrophic resistance to tornados, hurricanes and seismic events.
Brigham Young University Shear Wall and Auditorium EnCon Utah’s BYU’s auditorium and gym project consisted of a 16-inch-thick precast concrete radiused shear wall nearly 96 feet tall and over 400 feet long, precast stadia risers, and exterior CarbonCast® architectural cladding. With an architectural concrete mix and an acid etch finish, the single-color precast panels span the building horizontally. The low weight cladding of 53 psf lowers the overall building mass, reducing the seismic base shear and the seismic lateral force resistance system requirements. The building’s shear wall provided primary lateral resistance in this highly seismic region, and also provided the main support for the auditorium risers and roof trusses. The building is clad with an insulated carbon cast panel system to meet high-performance thermal requirements. Overall weight reduction in the exterior building system is paramount since Rexburg, ID is located in a Seismic Design Category D.
Yellowstone Club Due to a remote location and need for an expedited schedule, Stresscon Corporation used emulative design to convert the Yellowstone Club project from cast-in-place to precast concrete, reducing 24 months off the construction timeline. To meet the aggressive timeline, construction schedules facilitated a fast-track schedule through four seasons, battling extreme temperatures and weather with several severe freeze/thaw cycles. The use of offsite production of precast components was selected because of the durability of the product in extreme weather conditions, the ability to design for high seismic events, and the limited CIP concrete availability. It was important that all precast construction work met environmental standards with little impact to the natural surroundings. All the completed precast structures were built for the region’s seismic activity and also meet or exceed the International Energy Conservation Code (IECC) guidelines, assuring the Yellowstone Club community and residents that their units meet stringent energy efficiency requirements. Yellowstone Club is located in the Yellowstone Super Volcano
Facing Page: EnCon, Brigham Young University’s auditorium. Above: Yellowstone Club and Garden City High School.
area, another Seismic Design Category D, which created the need for design above and beyond other seismic zones. Stresscon’s seismic design requirements included grouted joints and connections, redundancy in concrete reinforcements, seismic hooks, and the use of vertical grout. The vertical grout joints are closure pours with stirrups projecting out of the walls, and an additional cage built and installed in the cavity prior to casting in order to create a rigid frame with members that can withstand seismic loads. Stresscon’s precast scope included a total of 4,565 premanufactured components, playing a primary role in the project design and construction. The precast pieces used include retaining walls, hollow-core, flat slabs, double tees, spandrels, non-insulated monolithic shear/shaft walls, columns, beams, shallow beams, soffit beams and bi-directional balcony slabs. In total, 16,900 cubic yards of concrete were erected over a 12-month period, and 1,342 truckloads were shipped. The featured monolithic balcony slabs were a new Stresscon product line and required design and installation of a new custom production facility. The production of these unique balcony elements, many with drastically different geometries, required bi-directional pre-stressing of most members. Traditional pre-tensioning was supplemented with post-tensioning of the cantilevered slab in order to resolve negative moments and provide continuity and ductility. Post-tensioning is an innovative method to apply transverse reinforcing to improve stability for gravity and seismic forces.
Garden City High School Depending on location, current safe room structures must meet FEMA 361 requirements for occupant density, debris missile impact, wind suction, and direct wind load speeds up to a 250 mph EF 5 rating. Roofs in these facilities are also required to handle specific combinations including upward and downward wind forces. Safe room structures are specifically designed to provide protection during tornadoes and hurricanes. Systems built in accordance with the FEMA 361 requirements provide maximum protection and minimize the probability of collapse, injury or death. Stresscon’s Garden City High School project is located in a highly tornadic area of Kansas and features a community safe room system designed to specific FEMA 361 standards. The school consists of three separate safe rooms, ranging in size from 5300 to 7600 ft². Lateral stability is obtained with shear wall panels ranging from 17
to 35 feet tall, and from 5 to 12 feet wide. In addition to the primary wind resistance they provide, the safe room walls also act as exterior walls in some locations. The safe rooms are all built as individual units to exist without structural support from the surrounding school building. Because of this, there are double interior walls that provide extra durability and required redundancy. The safe room system is composed of 8-inchthick gray structural precast interior concrete walls, and 13 inch insulated architectural precast exterior concrete walls. The walls require additional connections and reinforcement to meet the loads required. The wall panels are designed for high lateral loads, with a lateral load system consisting of floor and roof diaphragms transferring lateral forces to precast concrete shear walls, and down to the foundations. The wall panels included in this project are one and two stories high, in a single wall unit. The reinforcing is in two mats of mild steel in the 8” thickness. The principal reinforcing runs vertical, with shrinkage and temperature running steel horizontally. Often prestressed double tees with topping are used as the roof diaphragm, however, with this application, steel beams supporting a metal deck with CIP topping were used for the safe room roof system. Concrete is poured on top of this metal deck to distribute wind and seismic load forces to the shear walls, and to ensure that uplift force resistance is met. Special consideration was given to the connection requirement for the primary roof members, metal decking, and structural topping. The resultant embed plate was designed for gravity and uplift, with specific size to accommodate field tolerances, wall panel base connections transfer uplift, overturning, and shear requirements into the foundation. Specific considerations for topping and uplift of roof members are implemented into the design of the precast panels. In addition, these requirements plus shear loads are transferred into the foundation. Per FEMA 361, the safe room foundation must be designed for five times the load of a traditional structure. The use of interior double walls ensures that the safe room is a completely separate system that can stand on its own in case of catastrophic collapse of the surrounding structure. Precast concrete has become a common option for meeting unique building requirements and specially reinforced seismic systems. Precast was selected for both the BYU and Yellowstone projects because of the build locations and vast project sizes. The use of precast as the primary building material dramatically reduced overall project schedules, allowed year-round construction through extreme weather conditions, and emulated CIP design with precast components. Specifically designed and constructed with advanced strength and energy absorption features, precast construction provides long-term performance protection and is an economical way to create a safe room or seismic system requiring unusual load and force conditions due to its superior strength, and is an effective solution for meeting natural disaster requirements while maximizing safety, cost, and building use. ●
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ONLINE EXCLUSIVE
SIDEBAR TO INSIGHT: THOUGHTS FROM A TORNADO VETERAN
WHAT ARE THE ADVANTAGES PRECAST CONCRETE OFFERS IN PROTECTING STRUCTURES AGAINST THE ELEMENTS/CLIMATE CHANGE? ROBERT SHADE We meet the ICC 500 Debris Impact Resistance Test In 2016, we sent samples to Texas Tech University for debrisimpact-resistance testing: two 4-in.-thick and four 6-in.-thick precast, prestressed concrete panels using 5000 psi concrete tested per ICC 500-14 with a 15-lb wooden 2 × 4-in. projectile propelled at 100 mph. We had the joints between the panels tested as well as the wall panels themselves.
The following wall panels types passed the impact testing: • 6-in.-thick precast concrete panel with only one layer of 4 × 4 W4.0 × W4.0 WWM centered in the thickness • 6-in.-thick prestressed concrete panel concentrically prestressed in one direction with only 250-psi compression and no reinforcement (only concrete and prestressed strands) • 4-in.-thick precast concrete panel with only one layer of 4 × 4 W4.0 × W4.0 WWM centered in the thickness • 4-in.-thick prestressed concrete panel concentrically prestressed in one direction with only 250-psi compression and no reinforcement (only concrete and prestressed strands)
Some joints that are not used in precast concrete shelter construction failed the impact testing. Testing at the center of a 1⅛-in.-wide caulked joint (a standard ¾-in.-wide joint plus ⅜-in. PCI tolerance) using various types of caulk. Precast concrete wall panels that were 6 in. thick with standard polyurethane caulked joints each on face (without any additional armoring) passed the tornado debris impact testing. We currently arrange our standard ¾-in.-wide joint between precast concrete wall panels with a continuous 1-in.-diameter steel armoring rod, or use ship-lapped joints to meet ICC-500-14 joint armoring requirements for joints larger than ⅜ in. The results of our testing have been shared with the ICC-500 code committee, and a code change proposal submitted by PCI to increase the joint width between precast concrete wall panels in storm shelters to ¾ in. plus ⅜-in. industry tolerance was recently approved with modifications by the ICC 500 committee. If this ICC 500 code change makes it through the public comment process without modification, the change could be incorporated into the 2021 IBC through adoption of the most current ICC 500 standard.
WE MEET THE TYPICAL ICC 500 COMPONENT AND CLADDING WIND LOADS Roof down pressure = +125 lb/ft2 (max.)*
With very little add to the standard reinforcing in our designs for handling our products, our 48-in.-deep precast, prestressed concrete double tee can span up to 115 ft.
Roof down pressure = +125 lb/ft2 (max.)*
With the weight of our products and a 4-in. topping applied on the roof or the use of a pretopped double tee (using a 4-in. deck), long open spaces are achieved.
Roof down pressure = +125 lb/ft2 (max.)*
With the weight of our products and the use of standard connections to connect our products, a shear wall can be created with ease.
* These are very rough numbers that are typically conservative for the preliminary product design of double tees and walls.
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ONLINE EXCLUSIVE
HOW CAN THE PRECAST CONCRETE INDUSTRY USE ITS RESILIENCY ADVANTAGES AS IT BATTLES AGAINST COMPETING MATERIALS SUCH AS WOOD AND STEEL? ICC 500-14
What should the construction/building industry know about precast concrete’s attributes in providing protection against wind (hurricanes, tornadoes), fire, and earthquakes? A total–precast concrete structure has the natural ability to protect the owner’s investment. In an overall wall system, a reduction in thickness can be achieved by incorporating an architectural applied surface (such as textures, thin brick, etc.) and insulation cast into the prestressed wall. This can increase square footage of a building at no additional cost.
PCI-certified plants
Section 106, Inspections and Structural Observations, provides all but the peer review to meet all requirements that are needed to meet special inspections (making us an exception as a prefabricator).
Special inspections, etc.
Masonry, steel, and wood require on-site special inspections applicable to specific codes to be labeled as a shelter under ICC 500 design.
Product handling
Our product experiences more stresses than what it will experience to meet the final design required as a shelter. Connections are the main difference, which are increased to meet high-wind-event conditions.
Insulation of precast/ prestressed concrete products
Eighty-five percent of construction is done at the manufacturing plant; 15% is completed in the field with final transportation and placement with a crane at the jobsite. Disruption is minimal and number of days to complete the install is less than it takes to finish the foundation work.
What should our message in this area be to architects, building owners, and insurers? We have several examples of buildings that have been through tornadoes, where the structure was made using precast, prestressed concrete products. One had double tees, IT beams, columns, and spandrels where the structure survived and was reopened after windows, doors, interior masonry walls, and exterior masonry cladding were replaced. This is a testimony to what precast, prestressed concrete products can handle even when designed to a 30-year-old code (1970s to 1980s). Another example where a precast concrete load-bearing wall system was used with a steel roof survived and reopened minutes after the event. The exterior steel had to be replaced and all the structures nearby were destroyed. ●
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ONLINE EXCLUSIVE
Twisters occur around the world, but the United States is a major hotspot, with about a thousand tornadoes every year. Research has shown that Dixie Alley is now a more frequent destination of these violent storms. Photo: Federal Emergency Management Agency.
SIDEBAR TO PRECAST CONCRETE FEMA SHELTERS KEEP COMMUNITIES SAFE AND OFFER SHELTER FROM THE STORM
TORNADOES AREN’T JUST IN KANSAS ANYMORE BY MONICA SCHULTES While Kansas is in the middle of Tornado Alley, the infamous swath from Texas to South Dakota, research shows that tornadoes are now more likely to hit further east. The study identified a significant increase in the number of tornado reports in portions of Mississippi, Alabama, Arkansas, Missouri, Illinois, Indiana, Tennessee, and Kentucky. After a spate of tornadoes in late May of this year—a record 13 consecutive days with eight or more—a Washington Post headline screamed, “Extreme weather has made half of America look like Tornado Alley.”
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These “Dixie Alley” tornadoes tend to be deadlier than those in the Plains because of several factors: longer and larger tornado paths, larger population centers, mobile home density, and more nighttime tornadoes. Given the hills and trees, it’s harder to spot these storms until they are almost on top of you, as opposed to the Midwest, where you can often see them several miles away. Dixie Alley disasters are not just deadlier, but more costly as well. The research data could help with building code updates, identify vulnerable communities, increase risk awareness, and encourage emergency preparations. ●
ONLINE EXCLUSIVE
SIDEBAR TO ARCHITECT PROFILE: HUCKABEE
COST-EFFECTIVE DESIGN BY CRAIG A. SHUTT
Huckabee’s efforts to improve its design and products have paid off with a growing list of new and returning clients. It also has received accolades from its partners, such as Pogue Construction in McKinney, Tex., with which it has designed a number of storm shelters. Pogue’s team evaluated Huckabee’s integrated system and found it significantly more cost-effective than other designs.
The benefits of Huckabee’s precast concrete structure, according to Pogue’s report, include:
• Smaller Footprint This is possible because there is no furniture in the gym. “The storm shelter is one of the most expensive areas of a building, so any way to reduce the size is beneficial to cost,” Pogue’s team said.
• Reduce Impairments Using the gym as the storm shelter eliminates the need for impairments, such as overhead coiling storm doors that protect exterior windows and extremely thick exterior walls requiring the space to be larger for the same square footage.
• Off-Site Construction Benefits The precast concrete components are manufactured off-site and can be cast simultaneously with foundations, potentially
accelerating the schedule or allowing the contractor to focus on other portions of the building structure first, benefitting the overall construction schedule.
• Scheduling Advantages Once the precast concrete components arrive on-site, it takes about two weeks to assemble the structure. This compares to a conventional (non-storm-shelter) concrete masonry unit/steel joist gymnasium, which Pogue estimates takes about 3.5 times longer for structural assembly using trades that could be working elsewhere on-site. “This also provides schedule advantages on those other portions of the building.” These schedule benefits provided by the precast design “can provide additional benefits to general conditions and overhead on the project,” the team said. ●
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ONLINE EXCLUSIVE
SIDEBAR TO ARCHITECT PROFILE – HUCKABEE
HUCKABEE’S CONTINUED GROWTH BY CRAIG A. SHUTT
Huckabee was founded in 1967 in Fort Worth, Texas, by Tommie Huckabee with a focus on K-12 schools. Growth has come from new and returning clients and from providing more services to those clients, including offering solutions to issues often unrelated to design, such as assessment software and performing safety and security audits. Today, the firm is led by CEO Chris Huckabee, son of the founder. Growing from a 35-member staff in 1999 to 250 people today, the company ranked as the 192nd biggest architecture and engineering company in 2019 by Engineering News Record, up from 221 in 2018. ENR also named it the top educational design firm in Texas. It has numerous times been named one of the Best Places to Work in the nation.
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As Huckabee’s design concepts evolve, so too does the company. It currently operates six offices, which have opened organically as clients developed in a region, spreading out from its Fort Worth base. Offices are based in Austin, San Antonio, Houston, Waco, and Dallas. “Growth in local interest is the primary reason we open a new office,” vice president of engineering Benchmark Harris says. As more schools are required to incorporate tornado shelters and as school designs evolve, so too will the designs for Huckabee’s shelters. “We’re here because of the students. They drive every aspect of our firm and they’re the reason we’ll continue to innovate.” ●
ONLINE EXCLUSIVE
SIDEBAR TO ARCHITECT PROFILE – HUCKABEE
NSSA OFFERS RESOURCES BY CRAIG A. SHUTT
The establishment of the National Storm Shelter Association grew out of a concern to provide reliable, cost-effective protection during weather events after a series of devastating tornadoes hit Oklahoma in 1999. Finding no uniform specifications and few engineers qualified and willing to design storm shelters, the association set out to address issues of quality in the storm-shelter industry. The group promotes reliable practices and administers testing and engineering evaluation programs conducted by certified, independent entities that issue seals to qualified storm-shelter producers. It also works to develop standards and commentary to enhance the ICC/NSSA standard for the design and construction of storm shelters. ●
NSSA annual conference will be held November 13-14, 2019, in Birmingham, Ala. For more about the organization, visit www.nssa.cc.
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ONLINE EXCLUSIVE
SIDEBAR TO RESILIENCE IS THE NEW SUSTAINABILITY
RESILIENCY FLORIDA FOCUSES ON IMPROVED BUILDING CODES BY MONICA SCHULTES New construction is meeting higher resilience standards than in the past, thanks to the adoption of updated codes and public–private initiatives. One example is Resiliency Florida, which advocates for stronger building codes and has pursued increased investment in critical infrastructure and habitat throughout Florida. Huge strides forward have been made, but at least one significant pain point remains: the existing building stock. Kristin Jacobs, executive director, Resiliency Florida, is optimistic, but Florida still has a long way to go and the new norm doesn’t happen overnight. “When you look at the importance of building codes, most people don’t consider that a sexy topic,” Jacobs says. “I do because it is the key to the future.” That is how we slowly make changes and eventually incorporate holistic resiliency. One step in the right direction is the establishment of a Florida Chief Resiliency Officer to maximize the use of grant money and to focus on achieving statewide goals unique to that region, such as saltwater intrusion. Something as simple as mandating back-flow preventers and raising sea walls are some of the ways that building codes have already changed construction in Florida. In the aftermath of Hurricane Wilma in 2005, entire homes were blown away, while
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those built to higher standards were intact. “It is remarkable what building codes can do. Just by changing the way we build things we can become more resilient, and that is vital to our economy,” Jacobs says. Not surprisingly, municipalities become most receptive to scrutinizing their codes in the wake of tragedy. Hurricane Michael demonstrated that the use of superior construction enabled one house to survive the devastation on Mexico Beach (see sidebar). It was obvious that stronger, more modern construction using precast concrete withstood the storm. Resilient design principles in building codes are still a minimum standard and many architects and engineers take a more vocal stance in advocating for stronger and enforceable codes. The Federal Emergency Management Agency is proposing policies to incentivize states and municipalities to take a more proactive role in mitigating damage—and thus recovery costs. Each May, the Federal Alliance for Safe Homes joins with the International Code Council to mark Building Safety Month, a reminder of the need for adoption of modern building codes, a strong and efficient method of code enforcement, and a welltrained, professional workforce to maintain the system. ●
ONLINE EXCLUSIVE
SIDEBAR TO RESILIENCE IS THE NEW SUSTAINABILITY
LET THERE BE LIGHT BY MONICA SCHULTES
The typical profile of a precast concrete spandrel panel is quite large and does not let much natural light penetrate the structure. “The architect proposed raising the bottom of the panel to expose the stems of the double tees, which we had never done before,” says Farid Ibrahim, PE, SE, LEED, AP Director of Preconstruction Services at Clark Pacific. The stems were tapered to add consistency. “We painted the underside of the tees white. They line up with the 24-ft column spacing to emulate dentils. That kind of articulation draws your eye,” adds Jason A. Silva, AIA, LEED, AP, Partner/Design Principal, Dreyfuss + Blackford Architecture. They went to great lengths to provide natural light and ventilation on every level of the California State University parking structure. Using moment frame construction instead of shearwalls as the seismic-resisting system created an open and airy building with excellent passive security. The use of the HMF, low-profile spandrels, cable rail at the interior, and generous floor-to-floor heights allows natural daylight to penetrate deep within the structure. This also contributes to substantially reduced energy use. The cost-effective design allowed the addition of an innovative wayfinding system. A state-of-the-art parking stall detection system features wireless sensors attached to light fixtures that scan multiple parking spaces. The electronic occupancy detection alerts customers as to which levels have available spaces. ●
Using the hybrid moment frame, low profile spandrels, cable rail at the interior, and generous floor-to-floor heights allows natural daylight to penetrate deep within the structure. Photo: Kyle Jeffers, courtesy of Dreyfuss + Blackford Architecture.
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CALLFOR ENTRIES
57 The
th
AnnuAl PCI DesIgn
AwArDs
MARK YOUR CALENDAR
The 57th Annual PCI Design Awards will open for entries on May 20, 2019. Join us in our search for excellence and submit your projects electronically by August 19, 2019.
for the 2019 PCI Committee Days and Technical Conference, Featuring The National Bridge Conference on September 25-28, 2019.
Visit PCi.org for more InformAtIon AnD submIssIon DetAIls. Participate in the decisions driving our industry and impacting your business. Grow your industry knowledge with peer reviewed and non-peer reviewed education sessions. Network and get to know our industry’s leaders and spend time with your peers.
LOEWS O’HARE, ROSEMONT IL Registration opens June 25, 2019
“High Concrete saw our design as a wonderful opportunity to really show off their skills, talents and products. It has been a sincere joy to work with a group of precasters who are as engaged as they have been, willing to roll up their sleeves to work on solutions rather than seeing obstacles, and I am sure that they are proud of their efforts as much as we are.” Kai-Uwe Bergmann, AIA, RIBA, partner, BIG—Bjarke Ingels Group
THE NEW SHAPE OF PRECAST
Photograpy © Rasmus Hjortshøj—COAST
1200 Intrepid at the Philadelphia Navy Yard is the newly completed precast concrete work of art designed by worldrenowned starchitect Bjarke Ingels Group (BIG). The front entrance façade gently curves inward while stretching outward creating a startling and gravity-defying visual that mimics the curved bows of the nearby battleships. The unique engineering requirements of the project meant that the gravity
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loads flowed directly to the ground and were not tied to the steel frame. Almost every piece of the front entrance façade is unique. This very complicated project presented a challenge that required an innovative solution using technical, engineering and creative expertise, and would not have been possible without the use of BIM and 3D modeling. For more information on this project and others visit us at www.highconcrete.com/news.
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