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2017 QUALITY ISSUE

INSIDE: SPECIAL REPORT CalAPA’s Russell W. Snyder & Brandon Milar investigate the mysterious death of an asphalt recycling movement in California

Q&A with Mike Acott

National Asphalt Pavement Associtation President

Member Spotlight: SITECH NorCal


Publisher’s Letter Dear Readers, There’s an old management saw that you can’t make good decisions without good information. Unfortunately, these days we often have too much information and have a difficult time sorting through it all to find the valuable nuggets that will be useful to our businesses and organizations. In my previous career in journalism, I watched as the Information Age made a slow but steady march on the scene, hastened by networked computing, the internet and the World Wide Web, and finally smart phones and other devices that allow us to access information from anywhere and at any time. The trouble with information is there is good information and bad information. Knowing which is which is a daily challenge for the savvy information consumer. That’s why trusted sources of news and information are so important. In the mainstream media, established newspapers such as The Wall Street Journal, The New York Times, The Washington Post and news magazines produce high-quality information that meet professional standards of fairness and accuracy. In our state the highly regarded San Jose Mercury News, Sacramento Bee and Los Angeles Times have many well-deserved awards for journalistic excellence. When they get something wrong, they publish a correction or clarification. Their editorial pages are open to alternate points of view. On television, network and local TV news shows strive to report information accurately. Out on the internet, however, it’s still a wild frontier. Seemingly legitimate news flows around social media that is loosely constructed, poorly sourced and of dubious legitimacy. Studies have shown that such “fake news” continues to grow and threatens to overwhelm our citizenry that is trying to make sense of the world. Recent studies have found that propaganda is exploding across the globe via false or misleading social media postings, which is creating a real threat to democratic institutions. For the information consumer, it is important to understand where your news and information is coming from, and that it is a trusted source. For the asphalt industry in California, we take the responsibility to provide reliable information very seriously. Our weekly electronic newsletter, California Asphalt Insider, and our bi-monthly magazine, California Asphalt, are produced to professional standards and content is reviewed and fact-checked for accuracy. We make sure to cite our source material, and run corrections if we have made a factual error. We strive to generate valuable content that is available nowhere else and that helps advance knowledge and understanding of our industry for the benefit of all. We thank our readers, our advertisers, and most of all, the members of the California Asphalt Pavement Association who support this important activity. Sincerely,

Russell W. Snyder Executive Director California Asphalt Pavement Association 4

California Asphalt Magazine • 2017 Quality Issue


Contents Volume 21, Issue 5

4

Publisher’s Letter

8

Who Killed High RAP?

24

32

CalAPA’s Russell W. Snyder & Brandon Milar investigate the mysterious death of an asphalt recycling movement in California

Page 8

Flexible Pavements of Ohio

Q & A with Mike Acott President of the National Asphalt Pavement Association

Mike Acott

SITECH NorCal

Increasing safety, productivity and profitability through advanced worksite solutions

Page 24

On the Cover:

Front cover created by Yesenia Ramirez, Graphic Designer for Construction Marketing Services, LLC

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CALIFORNIA ASPHALT PAVEMENT ASSOCIATION www.calapa.net

HEADQUARTERS: P.O. Box 981300 • West Sacramento • CA 95798 (Mailing Address) 1550 Harbor Blvd., Suite 211 • West Sacramento • CA 95691 • (916) 791-5044 EXECUTIVE DIRECTOR: Russell W. Snyder, CAE, rsnyder@calapa.net TECHNICAL DIRECTOR: Brandon Milar, P.E., bmilar@calapa.net MEMBER SERVICES MANAGER: Sophie You, syou@calapa.net ADMINISTRATIVE ASSISTANT: Ritha Nhorn, rnhorn@calapa.net GUEST PUBLISHER: Russell W. Snyder, CalAPA PUBLISHED BY: Construction Marketing Services, LLC • P.O. Box 892977 • Temecula • CA 92589 (909) 772-3121 • Fax (951) 225-9659 GRAPHIC DESIGN: Yesenia Ramirez CONTRIBUTING WRITERS: Russell W. Snyder, CalAPA; Brandon Milar, P.E., Brian Hoover, CMS ADVERTISING SALES: Kerry Hoover, CMS, (909) 772-3121 • Fax (951) 225-9659 Copyright © 2017 – All Rights Reserved. No portion of this publication may be reused in any form without prior permission of the California Asphalt Pavement Association. California Asphalt is the official publication of the California Asphalt Pavement Association. This bimonthly magazine distributes to members of the California Asphalt Pavem­­ent Association; contractors; construction material producers; Federal, State and Local Government Officials; and others interested in ensuring that asphalt remains the high quality, high performance pavement choice in the state of California.

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California Asphalt Magazine • 2017 Quality Issue


Who killed high RAP?

Unraveling the mystery behind the death of a once-promising recycling movement in California BY RUSSELL W. SNYDER AND BRANDON MILAR

On Sept. 5, 2011, Caltrans Director Malcolm Dougherty wrote a letter to Assembly Speaker Pro Tem Fiona Ma stating that his department “recognizes the benefits of using a higher percentage of Reclaimed Asphalt Pavement (RAP). Caltrans is moving aggressively to introduce specifications and guidelines that will incorporate a higher percentage into our projects, while ensuring long-term performance of our paving materials.” Later in his letter, Dougherty announced that the department has accelerated an internal deadline, from June 2012 to November 2011, to develop a specification for 25 percent RAP, above the existing 15 percent standard, which would be incorporated into pilot projects in 2012 and evaluated. Ma was author of AB812, a bill introduced in the California Legislature that called for the department to boost RAP usage up to 50 percent. The department initially opposed the bill, but later withdrew its opposition when the bill was amended to set a goal of 40 percent, rather than a mandate, and called for a report to be submitted to the Legislature on progress toward the goal. The bill was signed into law in 2012 by Gov. Jerry Brown. The era of high RAP had finally arrived in California, or so it seemed. Since then, however, RAP usage on Caltrans projects has lagged far below these lofty 8

goals. Annual surveys conducted by the National Asphalt Pavement Association, sponsored by the Federal Highway Administration (FHWA), actually show RAP usage in California has been flat or trended downward, astonishing for a state famous for its progressive record on sustainability. In July of 2016, Caltrans released the report mandated by AB812, but it was only four pages, did not include a figure for RAP utilization, and instead cited various technical reasons why the department was unable to move forward. High RAP was, on the state level at least, virtually dead. So, who killed high RAP in California? This is a mystery with many twists and turns, and a final chapter that has yet to be written. But as the state ramps up to deliver billions of dollars worth of road repairs as a result of the legislative approval earlier this year of SB1, and Caltrans facing a mandate to find $100 million per year in cost-savings, perhaps high RAP can come back from the dead in California. ______________________________ More than 90 percent of the pavement in the United States, and in California, are surfaced with asphalt. Contractors combine aggregates, asphalt binder and other components into a blend that will meet the performance requirements of the pavement structure. While the binder only comprises about 5 percent of a dense mix,

it accounts for a significant proportion of the mix costs. The components of RAP are simply asphalt binder and aggregates, typically from available sources in the region. Contractors source RAP from the removal of existing pavements as well as from the production of asphalt mixes. This keeps RAP from going to landfills, reduces demand for aggregates, reduces the demand for virgin asphalt binder, reduces the transportation of these products and reduces the environmental impacts associated with these activities. While it is universally accepted that increasing the use of RAP in asphalt mixes provides both economic and environmental benefits, there is also general agreement that mixes containing RAP must meet the performance requirements for today’s complex pavement needs. Much of the focus is on the binder – the “glue” that holds rocks together to create asphalt pavements. The performance of an asphalt mix relies on two key properties of the asphalt binder: flexibility and stiffness. The flexibility component keeps the mix from cracking and falling apart under cyclic loading from traffic or temperature changes. Stiffness keeps the mix from deforming under heavy traffic loads or traffic loads during high temperatures. Asphalt binder suppliers characterize these binder characteristics with

California Asphalt Magazine • 2017 Quality Issue


California Asphalt Magazine • 2017 Quality Issue

Timeline of Key Developments in RAP:

The American Association of State Highway & Transportation Officials (AASHTO) and the Federal Highway Administration (FHWA) publish a report, Synthesis of Highway Practice No. 54, Recycling Materials for Highways, which provides information on how Reclaimed Asphalt Pavement (RAP) is used in pavements.

1978

1978

The National Cooperative Highway Research Program (NCHRP) releases a report, NCHRP REP 452 Recommended Use of Reclaimed Asphalt Pavement in the Superpave Mix Design Method: Technician's Manual is published providing guidance on the use of RAP.

2000

September 2000

The California Department of Transportation (Caltrans) begins to permit 15 percent RAP allowed in densegraded mixes on Quality Control/Quality Assurance (QC/QA) projects per a “nonStandard Special Provision (nSSP).

2004

2004

2007 Caltrans permits 15 percent RAP allowed in all dense-graded mixes per SSP.

2007

generally oxidized and stiffer from spending years on the roadway, would interact with virgin binder. In 1978, the National Cooperative Highway Research Program (NCHRP) published “Synthesis of Highway Practice No. 54, Recycling Materials for Highways,” which provided a state of the practice for the use of RAP in asphalt mixes. Since the publishing of the synthesis, the NCHRP, Caltrans, and other State DOTs conducted research related to RAP. An important outcome of the subsequent research was the development of a process to assess the properties of the combined binders. This process compares the virgin binder characteristics with the RAP binder characteristics. According to the procedures in Section 11.4 of the 7th edition of the Asphalt Institute’s MS-2, Asphalt Mix Design Methods, producing the blending charts requires plotting the Direct Shear Rheometer (DSR) and Bending Beam Rheometer (BBR) specified limits based on the project-specified PG binder and true grades of both the virgin and recovered RAP binders. In order to test the RAP binders, RAP binders are extracted and recovered with the use of a process using hazardous chemicals. Caltrans, as well as many contractor labs, no longer allow the use of these chemicals in their labs due to worker health and safety concerns. Even with this concern, Caltrans continues to require contractors to utilize these chemicals to extract and recover RAP binders for both mix design and quality control. For those contractors that do not allow the use of these chemicals, the extraction and recovery process are completed by third-party labs that are better equipped to handle the hazardous chemicals.

Nov. 12, 2009 Tom Carter, Teichert Aggregates, delivers a presentation on RAP best practices at the CalAPA Fall Asphalt Pavement Conference in Sacramento.

2009

the Performance Grade (PG) testing protocol. In designing a mix, the mix designer will blend the aggregates, the virgin binder (binder from an asphalt binder supplier), and other components in a proportion that results in a mixture that meets the project requirements. When designing an asphalt mix, the mix designer can replace a portion of the aggregates and virgin binder with the RAP. The binder in the RAP can contribute to the binder quantity in the mix, however, the RAP binder may have characteristics that are significantly different from the virgin binder. The aging of the RAP binder, resulting from environmental factors during its service life, results in a very stiff binder with minimal flexibility. The RAP binder characteristics significantly affect the balance between stiffness and flexibility. Mix designers can utilize various tools to address any negative effects from the aged RAP binder. These tools include “softer” binders, additives, or RAP percentage adjustments. Is there a limit to the amount of RAP that can be used in a mix? To answer this question, agencies and contractors need to understand the interactions of virgin and RAP binders in the mix. They need to understand the quantity of RAP in the mix where the characteristics significantly affect mix performance. The quantity of RAP binder is typically referred to as a percentage of the total binder (virgin binder + RAP binder) in the mix. The case for utilization of RAP in asphalt mixes has been building for many years. After the oil price shocks of the late 1970s and early 1980s, various research was done on reusing pavement millings into virgin mixes as researchers and engineers sought to understand how the binder from the RAP,

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As a result of the complexities in determining RAP percentages in mixes using blending charts, studies were conducted to identify percentages of RAP where there are no significant effects or where the effects can be mitigated with a simple change in virgin binder grade (such as one grade “softer”). This effort resulted in the adoption of a recommendation table in AASHTO M323 “Standard Specification for Superpave Volumetric Mix Design.” Subsequent studies validated the recommendation, including NCHRP 9-12 “Incorporation of Reclaimed Asphalt Pavement in the Superpave System.” By utilizing this approach, agencies and contractors have a technical basis to move forward with up to 25% RAP with minimal changes to the mix design process. The 7th edition of the Asphalt Institute’s MS-2, Asphalt Mix Design Methods, which Caltrans references for their mix design process, also incorporates the AASHTO M323 recommendations for binder selection when RAP is used. The Asphalt Institute publication also offers a generally accepted definition of “high RAP” – a mixture that contains more than 25 percent RAP. Contacted by California Asphalt magazine for this story, Peter T. Grass, P.E., CAE, president of the Asphalt Institute, which represents asphalt binder manufacturers, offered the following elaboration: “The Asphalt Institute has detailed guidance on how to design a mix with RAP in their MS-2 Manual, 7th Edition. For mixes with greater than 25 percent RAP, MS-4 states the RAP binder’s continuous (true) PG grade must be determined by using a recommended solvent extraction 10

and recovery procedure and testing the recovered sample per AASHTO M320. Blending charts or equations are used along with the true grade of the virgin binder to determine the properties of the blended RAP and virgin binder. This blended true grade at both high and low temperature should meet the requirements of the project binder grade which is typically based on factors such as traffic and climate. AI also recommends the use of cracking performance tests to assess the cracking susceptibility of high RAP mixes.” Overseas, meanwhile, some countries have raced ahead to embrace high RAP. For example, a 2015 report from the National Asphalt Pavement Association (NAPA) noted that in Japan, on average, 47 percent RAP is used in asphalt pavements. On Feb. 7, 2002, the Federal Highway Administration (FHWA) codified the concept of using recycled materials when it issued a formal policy on the use of recycled materials. “By providing leadership and technical guidance to the transportation community, FHWA will stimulate advancements in recycling technology and the discovery of new opportunities for the appropriate use of recycled materials,” said then-FHWA Executive Director Frederick G. Wright, Jr., in a transmittal memo announcing the new policy. The core of the FHWA policy, which remains in effect today, are contained in five principles: 1. Recycling and reuse can offer engineering,economic and environmental benefits. 2. Recycled materials should get first consideration in materials selection.

3. Determination of the use of recycled materials should include an initial review of engineering and environmental suitability. 4. An assessment of economic benefits should follow in the selection process. 5. Restrictions that prohibit the use of recycled materials without technical basis should be removed from specifications. Elsewhere in the policy, it states, “Recycling presents environmental opportunities and challenges, which, when appropriately addressed, can maximize the benefits of reuse. The use of most recycled materials poses no threat or danger to the air, soil, or water. Furthermore, careful design, engineering and application of recycled materials can reduce or eliminate the need to search for and extract new, virgin materials from the land.” California Asphalt magazine inquiries to the FHWA on this topic were directed to the agency’s public affairs office in Washington, D.C., where an FHWA spokesperson, Nancy Singer, offered the following statement: “Although FHWA encourages the reconsideration of recycled materials whenever possible – it is also FHWA’s longstanding position that any material used in highway or bridge construction should not adversely affect the performance, safety or the environment of the highway system. Beyond that, it is a state department of transportation decision to ultimately make the determination if recycled materials are appropriate or not for a particular project.” In effect, the FHWA was encouraging states to give recycled materials “first [ Continued on page 12 ]

California Asphalt Magazine • 2017 Quality Issue


[ Continued from page 10 ] 2010

2010

Caltrans permits 15 percent RAP in all dense graded mixes per the 2010 Caltrans Standard Specifications. Feb. 17, 2011

2011

AB812 by Assemblymember Fiona Ma, D-San Francico (pictured at left), is introduced into the California Legislature. The title of the bill is “Solid Waste: recycled concrete, recycled asphalt.” Among its provisions, the bill as introduced would require Caltrans to increase the allowable amount of reclaimed asphalt pavement (RAP) used in projects to 50 percent, from the existing level of 15 percent.

June 15, 2011

2011

The National center for Asphalt Technology (NCAT) holds a free “webinar” on Reclaimed Asphalt Pavement (RAP), titled, “Best Practices for RAP Management. ” The presenters are NCAT Director Randy West, Ron Sines, vice president of hot mix asphalt operations for Oldcastle Materials Group, and Gerry Huber, assistant director of research for the Heritage Research Group. June 28, 2011

2011 12

Lee Gallivan, asphalt pavement engineer with the FHWA, and Gerry Huber, Associate Director of Research, Heritage Environmental Services, a nationally known expert, attend a meeting at the Caltrans Translab offices on the subject of high-RAP.

consideration in materials selection” but also leaving to states to evaluate and develop standards for the use of said materials. NAPA, representing the asphalt pavement industry nationally, has taken a similar position. “NAPA encourages the use of RAP in asphalt pavements for cost savings and environmental benefits,” says Audrey Copeland, NAPA’s Vice President for Engineering, Research and Technology. “Through a partnership with FHWA, we've been tracking the use of RAP since 2009 and we continue to see an increase in the amount of RAP used to over 20 percent on average. Properly designed and constructed asphalt pavements with RAP have proven long term performance for more than three decades.” In California, cities and counties were the first to embrace high RAP in a big way. The City of Los Angeles, for example, specifies 50 percent RAP for its pavement mixes for city streets, and has been doing so for more than 20 years. “The City of Los Angeles specifies 50 percent RAP, and it is RAP that comes from city streets,” says Pascal Mascarenhas, Manager of Technical Services with Vulcan Materials in Southern California, which supplies mix to the City of Los Angeles. “It’s in their specifications. We use their RAP. It is a way to use what they mill off the streets. They reap the benefit of a much lower price because of that, and they are able to cover more streets. “We have not heard of any performance-related issues, in terms of cracking, in those mixes,” Mascarenhas added. “We do use a rejuvenating agent that is specified in ASTM

D4552 (“Standard Practice for Classifying Hot-Mix Recycling Agents”). We’ve been doing it for the last 20 years. That mix that we supply is mainly a halfinch C2 Mix. That mix is tested more frequently than any other mix that we ship out, more than Caltrans mixes, more than FAA (Federal Aviation Administration) mixes. So we test it for Quality Control, and the City does just as much testing. So it’s not this ‘one test for every 5,000 tons.’ They actually do more testing than we do, and some of their testing, besides the Marshall testing, they go and do IDT, they do Hamburg, they do rut-testing, and they love it because it’s been working for them.” The City of Los Angeles is so proud of its use of recycled materials, that it was the centerpiece of a groundbreaking ceremony held earlier this year for a new, state-ofthe-art asphalt plant being built for the city by CalAPA member Papich Construction. On Feb. 9, Los Angeles Mayor Eric Garcetti, speaking at the ground-breaking, said the nation’s second largest city “is taking big steps to improve services while keeping our commitment to minding the bottom line and protecting the environment in everything that we do.” The mayor’s press release further noted that, “The new plant will use 50 percent recycled asphalt material, up from 7 to 12 percent in the current mix. Recycled asphalt is more environmentally responsible and sustainable, and its increased use will reduce the City’s reliance on expensive and energy-intensive raw materials. The recycled material will come from the City’s own streets as they are repaved.” Another influential force for the use of high RAP is “The Greenbook,” or formally

California Asphalt Magazine • 2017 Quality Issue


California Asphalt Magazine • 2017 Quality Issue

Assembly Speaker Pro Tem Fiona Ma sends a letter to Caltrans Director Malcolm Dougherty saying she was “disappointed” by an earlier letter to her office from Caltrans indicating a lengthy process involved in evaluating a move to higher RAP.

2011

Aug. 10, 2011

Caltrans Director Malcolm Dougherty writes a letter to Assembly Speaker Pro Tem Fiona Ma stating that his department “recognizes the benefits of using a higher percentage of Reclaimed Asphalt Pavement (RAP). Caltrans is moving aggressively to introduce specifications and guidelines that will incorporate a higher percentage into our projects, while ensuring long-term performance of our paving materials.”

2011

Sept. 5, 2011

Assembly Speaker Pro Tem Fiona Ma, D-San Francisco, speaks at a conference in Monterey put on by the California Construction & Industrial Materials Association (CalCIMA), sponsor of AB812.

2011

Oct. 11, 2011

Oct. 18, 2011 Assembly Speaker Fiona Ma, D-San Francisco, tours a Vulcan Materials facility in Pleasanton, in part to see first-hand how RAP is incorporated in asphalt mixes. Conducting the tour were Vulcan’s Bart Mayoer and Max Pfaff.

2011

RAS group has been meeting regularly for many years. Longtime participants have expressed frustration that the current Caltrans specification language with regards to high RAP has, despite industry concerns, become too onerous and expensive, with additional testing requirements, which is a disincentive for contractors to maximize RAP usage. “Industry is very interested in using high percentages of RAP, and 25 percent RAP would be an easy goal to reach,” says Jack Van Kirk, a former Caltrans materials engineer who now works as Director of Asphalt Technology for George Reed Inc./ Basic Resources. Van Kirk is also a longtime co-chair of the Asphalt Task Group. “The problem is, the testing requirements in the specifications are such that it is not cost-effective for the contactor to use anything above 15 percent. Not only is it not economical, there is a concern about the use of solvents and worker safety. The current specifications require a lot of expensive solvent extractions. This is a negative thing that has discouraged contractors from going ahead with anything above 15 percent. So, our hands are really tied on the contractor level because if it’s not going to be economical, you’re not going to utilize anything above 15 percent. That’s where we are today.” The significant use of asphalt rubber mixes in California also creates an impediment to high RAP utilization. A legislative mandate in the 2000s kickstarted the use of recycled rubber in asphalt mixes, largely to find a use for used vehicle tires rather than have them end up in landfills. California is now the largest user of RHMA in the United States. Caltrans specifications currently do not permit RAP in rubber mixes.

Oct. 27, 2011 Assembly Speaker Pro Tem Fiona Ma speaks to the CalAPA Fall Asphalt Pavement Conference in Sacramento, highlighting her bill, AB812, on RAP, and said contractors could immediately begin using the specifications on pilot projects.

2011

known as the “Standard Specifications for Public Works Construction” that is widely used by local agencies in Southern California. The development of The Greenbook” is done under the oversight of Public Works Standards, Inc., which includes industry and agency representatives. The most recent Greenbook standards allow up to 20 percent RAP in “virgin” asphalt mixes. Higher percentages of RAP require additional testing, such as binder extraction and recovery. Many local agencies permit RAP in mixes, but some have been reluctant to do so, interviews with industry and agency representatives indicate. Some local agency representatives may not be aware, however, of a bill signed into law by the governor in 2014, AB2355, by Assemblyman Marc Levine, D-Marin County, which requires local agencies to adopt the most current standards as established by Caltrans on recycled paving materials, or report why the standards are not being adopted in a regularly scheduled public hearing of the local agency’s legislative or other governing body. The reporting feature of the bill took effect on Jan. 1, 2017. At the state level, the development of standards and specifications about asphalt are deliberated by a body of engineers and other technical experts known collectively as the “Rock Products Committee.” The committee, which is composed of various Caltrans and industry representatives, has various subcommittees, including an “Asphalt Task Group” and a “Sub-Task Group” devoted exclusively to RAP and Reclaimed Asphalt Shingles (RAS). The RAP-

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“We’re focusing on higher RAP, yet Caltrans is specifying rubber mixes for all surface courses with no RAP, so I just don’t know how you’re going to get it (RAP) in there if you don’t get it in the rubber mixes. Right now there is no RAP in rubber mix,” says Tim Denlay, Quality Control Manager with Knife River Construction, who is a frequent Rock Products Committee participant and also co-chair of the CalAPA Technical Advisory Committee. Pat Imhoff, Quality Control Manager with CalPortland, who serves alongside Van Kirk as the other Asphalt Task Group Co-Chair, offered a similar assessment. “One of the problems of putting RAP in rubber is that right now the spec requires 7.5 percent by total weight, minimum binder content, which is very difficult for some contractors to get that much binder in those mixes with the gradients and the aggregates that they are using. So if you’re going to put 5 percent to 15 RAP in rubber mixes –and it is most likely to be 5 percent – you have an additional 4/10th binder that is going to have to go into that mix. But when you try to squeeze more binder in it, your VMA (Voids in the Mineral Aggregate) will go down. Your voids are going to go down, and you’re not going to be able to meet the requirements that are there if you maintain the 7.5 percent total rubber binder content requirement. You’d have to go to a 7.9 percent, roughly, and still meet the same specifications. That’s just not practical or reasonable. It’s not using good engineering judgement to do that.” Adds Van Kirk, a noted expert in rubber pavements nationally and internationally: “Industry isn’t opposed to putting RAP in rubber. But Caltrans is concerned that it is going to 14

degrade. They are not willing to allow us to reduce that rubber binder content by the amount of RAP that is in there. That’s what has fouled this whole thing up. Here we are again, everyone is in agreement that maybe we can use 5 percent RAP in rubber, but Caltrans is not going to allow it because they are saying, ‘No, you’ve got to put 7.5 percent binder,’ which means we’ve got to, somehow, squeeze another half-percent binder into these rubber mixes that we are already having problems with designing.” Researchers have also been delving into questions about RAP, including the respected University of California Pavement Research Center (UCPRC), which has facilities on the campuses of U.C. Berkeley and U.C. Davis. In a recent interview with California Asphalt magazine, Dr. John Harvey, professor of engineering at U.C. Davis and director of the UCPRC, begins a conversation on high RAP with a rhetorical question, “Why do we want to use more RAP?” And then, as if on cue, he launches into an explanation that seems to be consistent with the FHWA policy guidance. “The reasons we would want to use more RAP are because it reduces cost, and because a large portion of the environmental impact – about one third of the greenhouse gas in a mix – is from the 5 percent by mass that is the binder. And that’s where a lot of the cost is, also. So, to the extent possible that we can safely use more RAP, and achieve the goal of at least the same performance as the same mix with no RAP, that’s our performance goal. The more RAP that we use and still achieve that performance goal, the more we can achieve the cost savings and reduce the environmental impact.”

“The third benefit of using RAP, besides cost and environmental impact, is reducing resource depletion,” Harvey added. “Aggregate depletion is important in certain regions of the state, particularly in the big urban areas, and longer transportation distances do carry additional environmental impacts. But the ‘big dog’ in terms of most of the main environmental indicators, like air pollution, greenhouse gas, energy use, is in the amount of virgin binder we are using.” It would seem, then, that high RAP is a no-brainer. Sustainable and cost-effective. What’s not to love? But a closer examination finds there’s much more to the story, and the answers are not so easy to come by. Another influential voice in this national debate is Adam Hand, Ph.D., P.E., Associate Professor of Pavement Engineering and Science at the University of Nevada, Reno Department of Civil & Environmental Engineering. Prior to joining the faculty of UNR in 2016, Hand was a longtime materials engineer for Granite Construction and sought-after presenter at asphalt conferences and technical forums. “I believe the biggest impediments to utilizing more RAP are recent national recognition of some poor performing high RAP/ RAS mixtures coupled with the lack of a set of reliable performance tests that can routinely be used for design and acceptance,” Hand told California Asphalt magazine. “One of the most important things the industry has learned is that not all materials used to soften asphalts, or to ‘drop PG grades’ to allow for higher recycled material contents, [ Continued on page 16 ]

California Asphalt Magazine • 2017 Quality Issue


[ Continued from page 14 ] Oct. 27, 2011

2011

Tony Limas, Granite Construction, delivers a technical presentation on RAP at the CalAPA Fall Asphalt Pavement Conference in Sacramento.

Nov. 4, 2011

2011

Caltrans releases updated specifications for Reclaimed Asphalt Pavements (RAP) and Recycled Asphalt Shingles (RAS).

2012

2012 Caltrans starts pilot project evaluations of Superpave mix designs.

2012

Jan. 26, 2012 AB812, amended to remove references to concrete, passes the Assembly. Aug. 13, 2012

2012

After making further amendments, AB812 is passed by the Senate and returned to the Assembly for concurrence on amendments. Aug. 16, 2012

2012

Assembly concurs with Senate version of the AB812, and sends it to the governor. The bill calls for Caltrans to “establish specifications for the use of reclaimed asphalt pavement (RAP) for up to 40 percent for Hot Mix Asphalt mixes.”

2012

Sept. 7, 2012 AB812 signed into law by Gov. Jerry Brown. Feb. 22, 2013

2013 16

Caltrans publishes an updated “Revised Standard Specification (RSS)” that moves toward “binder replacement” language, requiring contractors who use between 15 percent and 25 percent RAP to fractionate their RAP piles and allowing them to “bump down” one grade in their virgin binder if they choose.

are created equally and that the effectiveness of some are very short-lived. This leads to the need for a better understanding of binder/mix aging characteristics and, more importantly, a ‘balanced mix design’ procedure.” As suggested by Hand, the influence of RAS into RAP mixes has created a variable that is not fully understood yet, several people interviewed for this article have said. The binder in RAS is significantly more oxidized than the binder in RAP, raising questions about how it will interact with virgin binder. Another fairly recent variable is the influence of Warm Mix Asphalt (WMA), which allows for asphalt to be produced at lower temperatures. WMA has demonstrated numerous benefits, including reducing the temperatures for asphalt production, with a resulting reduction in fuel consumption and emissions, and also as a compaction aid. “Anecdotally, there were early indications that high RAP mixes, and maybe it had RAS – it was a little unclear – were failing extremely quickly in the Midwest,” recalls Harvey of the U.C. Pavement Research Center. “They have a harsher, cold-weather climate, and I don’t know the extent to which that contributed to the high RAP mixes failing early. If your RAP is not well blended with the virgin binder, then it can create performance issues. The question is: do we have enough certainty with the science and the technology that you have a really good probability that you’re not doing the wrong thing? Are you sufficiently certain that you’re not going backward by trying to go forward? So that caution is there.”

The Federal Highway Administration recognized this emerging issue and in 2014 published two technical memos on the subject that were widely read. The first memo, dated Oct. 20, 2014, alerted states that there appeared to be some performance questions that may or may not be related to high RAP and/or RAP with RAS content. A follow-up memo was issued on Dec. 11, 2014, further sounding the alarm. The December memo noted “a similarity in many of these pavements is the use of recycled asphalt shingles (RAS) to replace a large portion of the total asphalt binder in new pavements.” The FHWA recommended that state highway agencies using/ creating specifications for RAP and RAS should be aware of changes in the following AASHTO standards: M 32313: Superpave Volumetric Mix Design; MP 23-14: Reclaimed Asphalt Shingles for Use in Asphalt Mixtures; and PP 7814: Design Considerations when Using Reclaimed Asphalt Shingles (RAS) in Asphalt Mixtures. The following year, Caltrans proposed a Non-Standard Special Provision (NSSP) with new requirements for HMA with more than 15 percent RAP to ensure that the ultimate asphalt binder stiffness is within the requirements for the projectspecified binder. According to the proposed Caltrans NSSP of 2015, Type A mixes using more than 15 percent RAP require the use of asphalt blending charts to determine the maximum allowable RAP based on the properties of the projectspecified virgin binder and the recovered binder from the RAP. The result of the blending charts is the maximum RAP Pavement Binder Ratio (RPBR) that may

California Asphalt Magazine • 2017 Quality Issue


California Asphalt Magazine • 2017 Quality Issue

2013

Jay Behnke, P.E., president, State Testing, LLC, East Dundee, Il., presents on RAP and RAS at the CalAPA Spring Asphalt Pavement Conference in Ontario.

Caltrans hosts a one-day workshop on RAP and RAS at a Caltrans facility in Orange, featuring Dr. Randy West, director of the National Center for Asphalt Technology (NCAT) at Auburn Univeristy, and Dr. Richard Willis, lead NCAT researcher, discussing the latest research on the subject.

2014

Oct. 1, 2014

Oct. 20, 2014 The Federal Highway Administration issues a memorandum titled, “Recycled Materials in Asphalt Pavements (Reference NO. HIAP-1) alerted division administrators and others that an increasing number of state highway agencies reported premature cracking in relatively new asphalt pavements. A similarity in many of the pavements was “high content of recycled asphalt binder.”

2014

“In either case,” the CalAPA Member Alert went on, “a new JMF would be required and a change order written to compensate the contractor for the costs associated with a new JMF, the use of less RAP and more virgin binder, and additional quality control testing.” With the addition of these new requirements, contractors in many cases were reluctant to incur the additional time and costs associated with the new testing required to move to higher RAP amounts. It has left nearly everyone dealing with the issue frustrated. “The industry has been dealing with the stigma of high RAP and, unfortunately, it has been given a bad name,” said John Greenwood, General Manager of San Diego-based California Commercial Asphalt and past chairman of CalAPA. “It shouldn’t have this negative stigma. RAP can be broken down and analyzed as finitely as our virgin materials, rock and oil. It should be used in higher quantities – it just needs as much focus through engineering and technology as we give to everything else in asphalt.”

April 25, 2013

Oct. 24, 2014 Pascal Mascarenhas, Manager, Technical Services, Vulcan Materials, delivers a presentation on RAP at the CalAPA Fall Asphalt Pavement Conference in Sacramento.

2014

1) lowering the virgin binder grade to allow for higher RAP content; or 2) reducing the RAP percent.

Toni Carroll, Director of Quality for CalAPA member Graniterock, based in Watsonville, Calif., echoed similar frustrations. “I am originally from the Midwest,” she told California Asphalt magazine. “When I tell someone from back home that I currently live in California, typically one of the first things that someone says to me is some joke about California and their ‘green’ way of life. We’re proud of our environmental prowess as a state and it is recognized across the country and even internationally. Using RAP in HMA has been of high interest to the California HMA Industry for decades. In the past it was identified as a way to keep asphalt grindings out of the landfills but we are also able to create a higher sustainability for our natural aggregate resources and virgin crude oil that we desperately need for our future children’s generations.” New technology and techniques are needed to be applied to get high RAP back on track, Carroll says. “Technology has come a long way since RAP was originally used in HMA and agencies across the world have been able to successfully use 40 percent, 50 percent, and even 70 percent RAP in HMA mixes while maintaining a long-lasting pavement,” says Carroll, who until recently served as an industry steering committee representative on the Caltrans-industry Rock Products Committee. “Using high RAP requires more than our grandfathers’ methods of just mixing binder, rock, and RAP together to create a good mix. With the increased research and testing that has come out of places like NCAT, the Asphalt Institute, and even state DOTs across the United States, HMA suppliers

Oct. 29, 2014 Gerry Huber, Associate Director of Research, Heritage Environmental Services, delivers a presentation at the CalAPA Fall Asphalt Pavement Conference on the latest research in the use of RAP and RAS.

2014

be used based on the critical temperatures of the virgin and recovered RAP binders. A “Member Alert” to CalAPA members sent May 23, 2015 sought to explain the changes to industry, and concluded: “In a nutshell, this means significantly more testing for the contractor." If an existing Job Mix Formula (JMF) has a RPBR that is not within the limits shown on the blending charts, the possible alternatives for the contractor include the following:

17


have developed blending techniques and changes to virgin binder that can not only meet the specifications of today’s DOTs but can also exceed the life expectancy of our virgin aggregate roads in some situations. Unfortunately, although in the past California has led the way in sustainability and technical prowess, we have dropped woefully behind in regards to RAP usage on our state’s highways.” Other RAP impediments just defy explanation. One exasperated contractor, who asked not to be named so he could speak candidly, expressed frustration that Caltrans does not permit high RAP mixes used for temporary paving. That just seems irresponsible and a waste of taxpayer dollars, when the asphalt will only be in place for a short time, the contractor said. He also offered that RAP, in many cases, is a highly engineered product having already gone through a qualitycontrol design and production process prior to placement. “It already has quality built into the roadway,” the contractor said. “It’s graded. It’s got a certain binder content. So it can be used more effectively. That’s why RAP products are generally more consistent, more uniform than virgin material.” In its 2016 report to the Legislature on high RAP, Caltrans noted the various obstacles standing in the way of implementing higher amounts of RAP in pavement mixes, and said it was working collaboratively with industry representatives via the Rock Products Committee to understand the issues and implement changes in specifications and test methods to facilitate higher RAP utilization as long as performance expectations are met. The 18

department does not keep track of how much RAP is being used in mixes, Caltrans says. “Caltrans does not require its contractors to report on the exact quantity of RAP used by the contractor on each project,” says Sri Balasubramanian, chief of the office of Asphalt Pavements within the Caltrans Division of Pavements. “Our specification allows the contractor to use up to a certain percentage of RAP, depending where it is being used in the pavement structure. The contractor decides how much RAP they want to use on each project based on their inventory of RAP and the asphalt binder content in the RAP.” So, is this just a Caltrans issue? On this question, Harvey of the U.C. Pavement Research Center, pulls out the caution flag. Although his center receives some funding to conduct research for Caltrans on a variety of topics, Harvey says there is a body of evidence that, at minimum, raises some questions about high RAP that need to be answered. Shifting back into professor mode, Harvey offers the following explanation: “On a technical level, what is the question? On a technical level, there are two or three parts to the question. One fundamental question is, Does the RAP binder actually blend with a virgin binder to create a new binder? If it doesn’t blend 100 percent, then you don’t have the actual binder content that you thought you had. That’s a major issue for cracking, raveling and moisture sensitivity. Blending is driven by time and temperature. The longer the RAP and virgin binders are in contact, and the higher temperature when they are in contact, the more blending occurs. Now, if we’re using Warm Mix Asphalt, what

are we doing to temperature? We’re reducing it. So that is another question. Without Warm Mix, are we getting blending? And with Warm Mix, what’s going on? Are you getting blending?” And there’s more. “The second question is, if you are getting blending, what are the properties of the blended binder? If you get blending, what are your initial blended properties?” Harvey asked. “Caltrans, to my understanding, is now asking that contractors test and see what are the blended properties, on the assumption that there is full blending. I think that they are giving the benefit of the doubt that there is full blending. What they are asking for is that if you go over 15 percent RAP, you test what the properties are of the blended binder. The process they are looking at is extraction of the RAP binder and testing it and interpolating between the RAP and the blended binder based on the percentage RAP binder replacement you are using. They are looking at DSR charts and interpolating the results. “I know this takes time and money,” Harvey adds, “but how does that compare to the potential cost-savings of using more RAP from the contractor perspective, and how does that compare to the cost of early failure to Caltrans? I think the testing cost, and there is also hassle and time, are small relative to contractor cost savings and Caltrans risk of poor performance. I could be wrong, but that is my perspective.” And finally, Harvey says, “The third question, and this is a deeper unknown, is, Once you have blended the binder, does [ Continued on page 20 ]

California Asphalt Magazine • 2017 Quality Issue


[ Continued from page 18 ] Dec. 11, 2014

2014

A follow-up FHWA memorandum to the Oct. 20, 2014 FHWA memorandum provided further elaboration on pavement failures, noting that “a similarity in many of these pavements is the use of recycled asphalt shingles (RAS) to replace a large portion of the total asphalt binder in new pavements.” The FHWA recommended that state highway agencies using and/or creating specifications for RAP and RAS should be aware of changes in the following AASHTO standards: M 323-13: Superpave Volumetric Mix Design; MP 23-14: Reclaimed Asphalt Shingles for Use in Asphalt Mixtures; and PP 78-14: Design Considerations when Using Reclaimed Asphalt Shingles (RAS) in Asphalt Mixtures. The memorandum highlighted the challenge in zeroing in on the cause of the pavement failures, noting “Isolating a single contributory issue is difficult because there are many other issues besides high ABR (Asphalt Binder Replacement) that can affect how asphalt mixes will perform.” May 27, 2015

2015

CalAPA member Steve Escobar, president of Asphalt Pavement & Recycling Technologies (APART), Shafter, Calif., delivers a presentation on the effective use of RAP at the CalAPA San Diego Technical Committee meeting. He emphasized the need for good Quality Control/ Quality Assurance programs.

2015

Sep. 4, 2015 Caltrans Adopts Superpave mix design per Asphalt Institute MS-2. Oct. 28, 2015

2015 20

Steven Escobar, president, Asphalt Pavement & Recycling Technologies, Shafter, Calif., delivers a presentation at the CalAPA Fall Asphalt Pavement Conference in Sacramento on binder considerations when using RAP and RAS.

the blended binder age the same as a virgin binder? What happens over time? I’m not sure how much evidence there is to answer that question.” “These are worldwide questions,” Harvey says. “If you go to a conference on asphalt, this is what a lot of people are talking about. There’s a ton of research going on. Texas A&M is doing a ton of research, Illinois is doing work, there are other folks doing work on this. With regard to the first question regarding blending, our indications are that if you have long enough time and temperature, and the binder isn’t too oxidized on the RAP, you have a good chance of complete blending at standard blending times and temperatures, and storage in a hot bin afterward will help some. And this is where the Warm Mix comes in as a variable. The second question of what are the blended properties? There are also some doubts about how the chemical extraction may change the RAP binder. When you extract that RAP binder, test it, and interpolate it with the virgin binder, is the chemically extracted and then recovered binder from the RAP blended with the virgin binder the same as the blended binder that came from the RAP binder sitting on the rock and blending with the virgin binder through the process of going through a hot plant, sitting in a bin, transport and laydown? I don’t think that question is completely answered.” Speaking for the department on the RAP issue, Caltrans’ Balasubramanian issued the following statement to California Asphalt magazine: “Caltrans continues to work with industry to look for ways to use recycled materials in its

pavement. Use of Reclaimed Asphalt Pavement (RAP) in hot mix asphalt (HMA) is one of the ways to ensure sustainability of our resources. Sustainability is one of Caltrans’ core principles. “Caltrans has been allowing the use of up to 15 percent RAP for a while,” the Caltrans statement continued. “In the middle of 2011, Caltrans, working with the Federal Highway Administration (FHWA) and industry, started looking at increasing the amount of RAP used in RHMA. In 2013, specifications were developed, under the auspices of the Rock Products Committee, to increase the amount of RAP used to 25 percent on the surface layer and 40 percent in subsurface layer. Caltrans and industry continued to work on updating the specifications to where the use of RAP is based solely on binder replacement rather than by aggregate weight. Just as these specifications were getting ready to be finalized, in October 2014, FHWA issued a memorandum indicating that a number of State Departments of Transportation were reporting premature cracking in relatively new asphalt pavement when they used high content of recycled asphalt binder from RAP and Recycled Asphalt Shingles. Caltrans was also contacted by industry members regarding the premature cracking issue and wanted to work on an interim measure to address this issue. “Working with industry,” the Caltrans statement continued, “Caltrans developed interim specifications requiring the use of blending chart when using higher quantities of RAP, while continuing to work towards a more permanent solution to the premature cracking issue. A subtask group, consisting of Caltrans and industry personnel, is currently working with Dr. John Harvey and his team at

California Asphalt Magazine • 2017 Quality Issue


California Asphalt Magazine • 2017 Quality Issue

The National Asphalt Pavement Association (NAPA) publishes “Best Practices for RAP and RAS Management,” No. 129 in its Quality Improvement Series. The report is authored by Randy C. West, Ph.D., P.E., Director, National Center for Asphalt Technnology (NCAT) at Auburn University. The report is sponsored by the U.S. Department of Transportation, Federal Highway Administration.

2015

Dec. 1, 2015

The National Asphalt Pavement Association (NAPA) publishes “High RAP Asphalt Pavements: Japan Practice – Lessons Learned., No. 139 in its Information Series. The report is authored by Randy C. West, Ph.D., P.E., Director, National Center for Asphalt Technnology (NCAT) at Auburn University, and Audrey Copeland, Ph.D., P.E., NAPA Vice President, Engineering, Research & Technology. The report is sponsored by the U.S. Department of Transportation, Federal Highway Administration.

2015

Dec. 1, 2015

April 21, 2016 At the CalAPA Spring Asphalt Pavement Conference, an expert panel discussion on RAP and RAS is held featuring Bob Humer, Senior Engineer, Asphalt Institute, Pascal Mascarenhas, Manager, Technical Services, Vulcan Materials and Edgard Hitti, QC/QA Group Manager, Alon Asphalt.

2016

She remains bullish on the future of high RAP in California. “I’m optimistic that it will increase by another 10 to 15 percent in five years because of ever greater emphasis on sustainability and limited transportation budgets.” UNR’s Hand offers a similar assessment. “National efforts to understanding aging behavior, coupled with a relatively simple mix cracking test, will allow for rational design of HMA regardless of RAP dose,” he said. “I also believe we will see the use of very high RAP mix that is produced at very low temperatures. The industry knows we must produce good performing asphalt mixtures to maintain our current infrastructure and market share in this competitive industry. I am confident the asphalt industry will do just that.” Focusing on California, Graniterock’s Carroll is not quite as optimistic. “Although there is still hope that Caltrans will revise its specifications to allow for higher RAP usage using reasonable engineering controls to avoid premature cracking, there is not much optimism that this will occur over the next few years,” she said. “Industry suppliers are settling into acceptance that 15 RAP may be all that we can provide for Caltrans. Meanwhile, many local agencies like cities and counties have seen the benefits of high RAP and are willing to work with suppliers and technical experts from across the world to pilot projects using high RAP. These agencies are continuing to show the world who California truly is and are benefiting from strong roads with decreased rutting or shoving. It is industry’s hope that these agencies will be able to show Caltrans over the years that there is little to fear in high RAP mixes

May 23, 2016 CalAPA issues a “Member Alert,” authored by CalAPA Technical Director Dr. Rita B. Leahy, Ph.D., P.E., a White Paper of various technical considerations regarding Reclaimed Asphalt Pavements (RAP) and Recycled Asphalt Shingles (RAS), including updates on AASHTO Standards, test methods, current research and history of recent efforts to increase RAP utilization in California.

2016

the University of California Pavement Research Center, to look at tests to identify the potential for pavement cracking. This research will help with the development of specifications to address the premature cracking issue. Hopefully, in the near future, Caltrans, industry and academia, working together, will be able to come up with a solution to check for premature cracking. This will enable the use of higher amounts of RAP in HMA and support the sustainability of asphalt pavements.” Ultimately, the issue may boil down to appropriate risk. Since agencies tend to lean toward conservative specifications, more requirements and testing are put in place to minimize the agency risk on the use high percentages of RAP in asphalt mixes. However, adding excessive testing or placing too much risk on the contractor can impede progress. The FHWA recognizes the benefit of the agency and contractor sharing the risk. FHWA RD 02-095 Optimal Acceptance Standards for Statistical Construction Specifications Section 39.1 provides a definition of risk and outlines acceptable risks for both parties. Rita B. Leahy, Ph.D., P.E., a consultant and former CalAPA Technical Director, agrees that a lot of the high-RAP hubbub comes down to fear of the unknown and overly cautious specifications. She thinks any concerns about performance can be addressed through consistency and control, such as effective stockpile management, processing and handling. Further, she said she thinks it is critical to characterize the RAP binder and appropriate blending with the virgin binder “to minimize binder-sensitive distresses – low temperature cracking, aging, durability and fatigue-cracking.”

21


June 22, 2016

2016

Caltrans releases technical guidance titled, “Construction Procedure Directive” No. 16-8, dated June 22, 2016. The guidance states, “Recently there has been some attention on some nationwide projects with high asphalt binder replacement from reclaimed asphalt pavement, recycled asphalt shingles, or both,” The memo further states, “The type of failure is cracking that could be caused by excessive stiffness of the blended asphalt binder.” It goes on to say that until the issues are resolved, the department was issuing a “nonstandard special provision” with new requirements for HMA that include more than 15 percent RAP. The changes require the issuance of a change order to require the contractor to produce asphalt binder blending charts that will show the maximum allowable RAP pavement binder rations (RPBR) that may be sued given the project’s specified asphalt binder, and the properties from the virgin binder and recovered binder from the RAP.” July 18, 2016

2016 2016 22

The report on RAP mandated by AB812 is delivered by Caltrans to the Legislature. The four-page report says “controlling the performance of high RAP content in HMA requires careful control on how much binder is replaced. This led Caltrans to transition to the basis of the RAP usage limit from aggregate weight to binder replacement.” Oct. 27, 2016 Adam Hand, Ph.D., P.E., Associate professor, Pavement Engineer, University of Nevada, Reno, delivers a technical presentation on RAP and RAS at the CalAPA Fall Asphalt Pavement Conference in Sacramento.

if it is designed appropriately and placed in the correct applications.” For the member of the state Assembly who championed high RAP more than seven years ago, Fiona Ma, CPA, now a member of the state Board of Equalization, says the technical debate appears to have strayed from the original intent of her bill. “I’ve always been a champion of a greener California, which is why I was proud my AB 812 set the bar for greener roads by utilizing RAP,” she told California Asphalt magazine. ”While I am disappointed that California has not reached the goals set in my AB 812, I urge our leaders to continue to fight for innovation and efficiency to keep our roads green and conserve California’s natural resources.” All of which circles back to the original question: Who killed high RAP? If you’ve read this far, you can see there is no simple answer. At the state level at least, a high-minded policy goal collided head-on with a risk-averse bureaucracy and mixed messages from the engineering community. As the author of AB812 and others have suggested, it will take a renewed commitment to innovation and sustainability to resurrect high RAP from the dead and return it to its rightful place as an important part of an environmentally-friendly, costeffective pavement strategy in California. CA ______________________________

REFERENCES:

Russell W. Snyder, CAE, is Executive Director of the California Asphalt Pavement Association (CalAPA). Brandon Milar, P.E., is Director of Technical Services for CalAPA. This article was reviewed by Rita B. Leahy, Ph.D, P.E., and Ritha Nhorn, Technical Training Coordinator of CalAPA.

West, R., Copeland, A. (2015) High RAP Asphalt Pavements: Japan Practice – Lessons Learned, Information Series 139, National Asphalt Pavement Association.

U.S. Department of Transportation, Federal Highway Administration, “FHWA Recycled Materials Policy,” Feb. 7, 2002. Accessed via the web on Aug. 24, 2017: https://www.fhwa.dot.gov/ legsregs/directives/policy/ recmatpolicy.htm Burati, J.L.; Weed, R.M.; Hughes, C.S.; Hill, H.S. (2003), Optimal Acceptance Standards for Statistical Construction Specifications, FHWA RD 02-095, Federal Highway Administration Epps, J. (1978) “Synthesis of Highway Practice No. 54, Recycling Materials for Highways” National Cooperative Highway Research Program (NCHRP) MS-2 Asphalt Mix Design Methods (2014), the Asphalt Institute McDaniel, R., Anderson, M., (2000) Recommended Use of Reclaimed Asphalt Pavement in the Superpave Mix Design Method: Technician's Manual, Report No. NCHRP REP 452, National Cooperative Highway Research Program, National Research Council (NCHRP), Washington, D.C. West, R., (2015) Best Practices for RAP and RAS Management, Quality Improvement Series 129, National Asphalt Pavement Association.

California Asphalt Magazine • 2017 Quality Issue


Q&A

Mike Acott & Clifford Ursich President, National Asphalt Pavement Association

President & Executive Director, Flexible Pavements of Ohio Reprinted with permission from Flexible Pavements of Ohio

Editor’s Note: If you’ve ever had opportunity to see things from thirty-thousand feet – as it were, you can understand what it is to have the “long view” of things. Such is true when you have opportunity to sit down with an industry leader. Recently, I had a Q&A session with Mike Acott, President of the National Asphalt Pavement Association to learn his viewpoint as to the future of the asphalt industry and the role of thinlays. First, about Mike… Mike Acott is a past Chairman of the Global Asphalt Pavement Alliance. His career activities involve nearly 35 years of experience in the pavement industry in Europe, South Africa, and the United States, including experience with aggregate and bitumen suppliers, and management of an asphalt construction company. He has been President of NAPA since 1992, and has helped develop partnerships with Government and Union partners that have resulted in an improved workplace environment. This has included successful national initiatives on engineering controls, warm mix, and best practices that have resulted in reduction in workplace exposure. He has been active in the Transportation Research Board and is a former member of its Executive Committee and is a Board member of the National Center for Asphalt Technology (NCAT), based at Auburn University. He has a Bachelor of Science degree in Physics – with honors – and a Master of Science degree in Civil Engineering for his work on foamed asphalt. Clifford Ursich: Mike, thank you for taking time for this question and answer session. Readers of Ohio Asphalt will be very interested to learn of what’s ahead from your viewpoint

Mike Acott

President, National Asphalt Pavement Association

Clifford Ursich

President & Executive Director, Flexible Pavements of Ohio

Mike Acott: You’re very welcome. It’s always a pleasure to talk about asphalt and the future of our industry. CU: In recent years, NAPA has completed market research to better understand what’s on the minds of roadway owners and motorists.Can you share about the findings of the research? MA: As part of our broad industry market research, we have conducted interviews and surveys of road owners, pavement designers, and the driving public to best understand their needs and opinions. One thing that was clear from the interviews with leaders at departments of transportation and public works agencies is that they are severely constrained by their limited budgets. They recognize the problem we have across the county of deficient infrastructure, but they are not able to keep pace with current maintenance and improvement needs. In our most recent survey of pavement designers, completed in November 2016, the top three priorities when it comes to pavement assets are performance, cost, and speed of construction. This has been a consistent theme across all our market research starting in 2013, driver and road owners alike want pavements that provide a high level of performance, [ Continued on page 26 ]

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California Asphalt Magazine • 2017 Quality Issue


which includes a smooth ride and long life; that are cost-effective to build and maintain; and that can be built, maintained, and expanded with minimal delay for the driving public. Thinlay meets these needs and expectations. CU: Could you please describe to our readers what is a Thinlay? MA: Thinlays are thin-lift asphalt overlays designed for pavement preservation and that can successfully extend the life of structurally sound pavements. They can be placed as thin as 5/8 inch, but may be thicker when required to correct surface distresses, such as cracking, rutting, or roughness. The mixes use the same materials as other asphalt mixtures — aggregates, binders, and additives — and may be produced by any asphalt mix producer and placed by any asphalt laydown contractor. CU: Does Thinlay replace conventional overlay materials? MA: No, Thinlays don’t replace conventional overlays, which are more appropriate when more significant structural, roughness, or drainage improvements need to be addressed. As with other pavement preservation tools, Thinlay mixes aim to extend the life of a structurally sound pavement that is in good condition with minor or no distress. CU: How does the function of Thinlays differ from traditional asphalt strategies, such as overlays or inlays? MA: Overall, I don’t believe many people would see a different function for Thinlays versus traditional strategies. Any time we place an asphalt mixture, its function is to provide a smooth, safe, long-lasting surface. The difference is that Thinlay mixes are designed for pavement preservation, which is often described as keeping good pavements good. They are designed to be durable and crack resistant, but, like other pavement preservation strategies, they will not correct structural distresses, such as fatigue cracking. This is why we stress the need to apply the right treatment at the right time to the right pavement. CU: What types of roadways are good candidates for a Thinlay application? MA: Thinlays can address most pavement surface issues, if the severity of these issues is not excessive, which is why it is important to evaluate the extent and severity of any distresses to determine before any pavement preservation treatment is applied. In 26

Above: NAPA President Mike Acott spoke in 2013 at the CalAPA Fall Asphalt Pavement Conference in Sacramento.

fact, a New Jersey Department of Transportation official recently commented that when a Thinlay is applied to a road in need of preservation but in otherwise good condition, the state is getting about 14 years of life from the thin overlay versus just seven years when applied on a pavement in poor condition. Thinlays are excellent for correcting raveling and restoring skid-resistance. They can correct minor rutting (less than a quarter inch), and they are also the only preservation treatment can offer a significant improvement in ride quality. However, a Thinlay cannot be expected to make an excessively rough road smooth. Thinlays are also as good as or better than any other treatment for sealing longitudinal and transverse cracking. When a pavement has isolated alligator cracking, Thinlays can be used if these areas are patched before overlaying. Thinlays may also be used after milling to improve smoothness or profile, or when distressed surface layers have been removed. CU: What attributes of Thinlays make them wellsuited for preserving pavement condition? MA: When it comes to performance, the data shows that Thinlays outperform other preservation treatments for most pavement conditions. Because Thinlays can correct surface defects, they are also better than other pavement preservation treatments at improving ride quality, reducing noise, and improving surface drainage. They can also strengthen the pavement structure. Because [ Continued on page 28 ]

California Asphalt Magazine • 2017 Quality Issue


[ Continued from page 26 ]

no special equipment is needed to produce or place Thinlay mixes, a wide number of contractors are available to do Thinlay work. Thinlays can also be designed using polymer-modified binders for improved strength and cracking resistance. High friction aggregates can be used for improved skid resistance. CU: How is constructing a Thinlay different from other asphalt pavements? MA: Because Thinlays are placed in thin layers, there are a few differences from constructing thicker sections. First, they cool more quickly, so it is important to avoid placing them in cold temperatures and to keep rollers close behind to the paver. The MultiCool software and app are a good tool for determining how fast a mix, including a Thinlay mix, will cool under different environmental conditions. Warm-mix asphalt can also be beneficial for Thinlays as it allows mixtures to be compacted at lower temperatures. When placed thinner than 1.5 inches, compaction testing will not be possible. A roller pattern should be established at the start of the job using non-destructive density gages and periodically checked, especially if environmental conditions change. One of the most important steps in placing any type of overlay is the tack coat. Tack should be uniformly applied and allowed to break and set so that construction equipment does not pull up the tack during construction. NAPA has some good guidelines on the placement of tack coats. There is no difference in the paving equipment used to place a Thinlay. Contractors should balance the plant production, trucking, paving speed, and compaction so that the paver moves at a steady pace for the best quality. Again, NAPA has some good guidance on how to balance production rates. CU: How are mix design and quality assurance provided in Thinlay manufacturing and paving? MA: Thinlays use the same quality control procedures and tests used for other asphalt mixtures; for this reason, Thinlays likely have the most rigorous mix design and quality control procedures in place of all preservation treatments. The only difference from other asphalt mixes in quality control is testing for compaction, which cannot be done on layers thinner than 1.5 inches. CU: How can Thinlay reduce the life cycle cost of pavement ownership?

MA: The cost effectiveness of pavement preservation is well established. By preserving pavements in good condition, an owner can avoid costly reconstruction or rehabilitation. One thing often overlooked, however, is that we need to look beyond preserving just the surface of the road; the road structure needs preservation, too. We should not allow the structure to deteriorate from the bottom up and just hold the surface together. Agencies need to look at their pavement management systems and see how each treatment performs under different distresses. Only then can they really know which is the right treatment for the right road at the right time. In addition, because Thinlays can add structure to a road, so long as distresses have not started, they can be used to increase carrying capacity while also preserving the pavement. This can be important when changing growth patterns or traffic levels mean a road is expected to carry more traffic than it was originally designed to support. Being able to strengthen a road as needs increase while simultaneously extending pavement life is a very cost effective strategy. CU: How does Thinlay contribute to the sustainability of the pavement? MA: Sustainability is about improving economic, social, and environmental profiles of a product. Thinlays do this well by preserving a pavement’s structure, which can extend pavement life and forestall the need for rehabilitation or reconstruction. As with other asphalt pavement mixtures, recycled materials and warm-mix asphalt may be used to improve the environmental profile of a mix. And by improving surface smoothness, drivers gain improved drivability and reduced rolling resistance, which improves fuel economy and reduces CO2 generation. A benefit of small stone size Thinlays is that they have a negative surface texture compared to a positive surface texture for chip seals. This negative surface texture generates less noise and reduces rolling resistance. CU: Do you see a future for Thinlays beyond pavement preservation? If so, what might that be? MA: Yes, several states are using small stone (3/8" max. aggregate size) SMA for high volume traffic. For heavily trafficked roads, Thinlays can be part of a staged construction approach, where the total depth required to develop a Perpetual Pavement is built over time. For example, a Perpetual Pavement design for a road may require 10 inches of asphalt. With [ Continued on page 30 ]

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California Asphalt Magazine • 2017 Quality Issue


staged construction, the pavement is constructed with 8 inches of asphalt and then overlaid with a Thinlay at set intervals to increase the structure before distresses begin. Because the structural increase happens in parallel with the preservation activity, the interruption for drivers can be minimized and agencies can plan for the expense.

a pavement to a high level of performance and drivability with minimal construction delay. Knowing the needs of today’s road owners, and the budget stresses they face, I am certain that Thinlays will be used increasingly to preserve and maintain pavement assets and to ensure a smooth ride for drivers in a cost-effective manner.

As the industry works to implement performance testing for asphalt mixtures, we expect to see additional innovations for Thinlays that optimize the use of RAP, polymers, crumb rubber, and mix type. Adjusting mixes to optimize rolling resistance, noise, and skid resistance will also occur.

To assist in the deployment of Thinlays and the use of best practices, the National Center for Asphalt Technology is developing a Thinlay guidance document, which will be published later this year.

CU: What has been learned since the PEC market research that gives insight to Thinlay future applications? MA: The market research I mentioned earlier helps inform the research plans of the Pavement Economics Committee and the communication of research findings, as well as the deployment activities overseen by the Asphalt Pavement Alliance. For the pavement preservation marketplace, these needs of the public and road owners are met well by Thinlays, which can cost-effectively return

30

CU: Thank you very much Mike for your valued insight. MA: My pleasure. CA Clifford Clifford Ursich is President and Executive Director of Flexible Pavements of Ohio, a non-profit construction trade association.

California Asphalt Magazine • 2017 Quality Issue


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California Asphalt Magazine • 2017 Quality Issue

14635 Valley Blvd., Fontana, CA 92335 10918 Shoemaker Ave., Santa Fe Springs, CA 90670

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MEMBER SPOTLIGHT

SITECH NorCal – Increasing Safety, Productivity and Profitability Through Advanced Worksite Solutions BY BRIAN HOOVER

Trimble portfolio of products. They offer maintenance, repair and field services and, in most cases, they can have a specialist on a job site within 24 hours. SITECH NorCal also has Trimble certified trainers, and offers regularly scheduled classes at their San Leandro facility, including Business Center-HCE, GNSS Base & Rover, Machine Control, and certification for Intelligent Compaction Equipment Training. These trainers are available to teach classes onsite at the customer’s request.

Above: Asphalt paver equipped with Trimble® PCS900 3D paving system producing accuracies to 0.01 feet (3 millimeters).

New CalAPA member SITECH NorCal is an authorized Trimble® dealer, service provider, and certified training facility offering a complete portfolio of construction technology systems to the civil engineering, construction, heavy highway, and aggregate industries. Their product lines include machine control solutions, on board scales, site positioning solutions, engineering software, civil robotic total stations, optical instruments, construction lasers, laser levels, and accessories. As an independent, factory direct dealer, they also sell and service Crain, Loadrite™, Seco and Spectra Precision products. 32

Willie Ghilotti - Ghilotti Construction “We specialize in highway and heavy construction, and SITECH NorCal has gone over and beyond to supply us with the latest Trimble technology. Our productivity has increased dramatically from using applications like Trimble 3D technology out in the field, where we once used time-consuming staking techniques. We now have better control of our production, moving us from one job to another faster and more safely. SITECH NorCal has contributed greatly to our success and growth over the past five years as we continue to invest in our people, technology, and equipment.”

With full operating facilities in San Leandro and Chico, SITECH NorCal’s experienced professionals have 20+ years experience working with the

Slade Leahy - Ken Leahy Construction “We began a relationship with SITECH NorCal in the early 2000s when we invested in a single piece of machinery. Today, we have full robotic Trimble technology on three pieces of heavy equipment and we have benefited with more production and fewer mistakes. I would say that our productivity has increased by 50 to 60 percent in some applications and we are significantly more profitable because we have fewer workers on the ground and handle the material less. SITECH’s professional and knowledgeable support staff are always just a phone call away with quick and concise solutions. They are the best at what they do and we wouldn’t go with anyone other than Trimble and SITECH.”

SITECH NorCal’s Aggregate Solutions team provides production and safety technologies for their customers’ entire aggregate operations. This includes a payload management segment that tracks material from extraction, hauling, plant

California Asphalt Magazine • 2017 Quality Issue


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1. SITECH NorCal Field Service technicians can be dispatched to your jobsite to keep your equipment up and running. 2. The Trimble® Control Box/Display Unit is the main hub of the machine control system – it’s user friendly and easy to operate.

3. On-site construction positioning equipment can be used for checking grade, collecting topographic data, and measuring volumes.

production, and load out with Trimble Loadrite payload solutions, and a web-based reporting solution: InsightHQ. They also offer solutions for drill-planning and positioning, to ensure the most accurate blasts with precision hole placement. Graders, dozers, and excavators equipped with Trimble grade control solutions can ensure that haul roads are graded for truck optimization and proper drainage, while UAV (drone) photogrammetric survey solutions use analytics to confirm inventory levels. A SITECH NorCal aggregate engineer is able to access the current quarry configuration and make suggestions that enable aggregate producers to become more competitive and efficient. Troy Sanstrum – RevCon, Inc. “SITECH NorCal set up the Trimble technology on-site for one of our dozers and it was just amazing. I am the biggest skeptic there is, and not very comfortable with change. The pros at SITECH NorCal convinced me in a very short period of time that Trimble was the way to go for our machine control needs. It was an expensive investment and worth every penny and then some. The screen displayed every slope, every cut, every fill, and it showed every blade tip as well. It is like having two extra really talented crew members on the job. If you are in this business and not investing in this technology, you are being left behind. The effect on production, safety, and profitability is immediate and a real game changer in our particular business.”

4 Bob Barton – Barton Laser Leveling, Inc. “There are a lot of advantages to having Trimble technology other than just production. By saving us time from one jobsite to another, this technology has allowed us to do what we do, better, faster and cheaper. At the end of the day, this enables us to retain jobs and revenue that may have otherwise gone to a competitor. SITECH NorCal understands this technology and they have done such an outstanding job teaching and training our crew on how to properly implement and apply it to our particular construction niche. It is important to look at the whole picture and not just the production or yield savings. It is fun and exciting to be on the edge of the technology curve and enjoy the immediate benefits of the return on investment.”

SITECH NorCal provides powerful and comprehensive Trimble construction technology solutions that perfectly fit the needs of contractors of all shapes and sizes. From machine control, site positioning, software applications, lasers, and aggregate solutions, SITECH NorCal is able to provide the support, expertise, and experience needed to increase productivity and profitability using advanced worksite solutions. To learn more about SITECH NorCal and how they can help your business, log on to their website at www.sitechnorcal.com or call their San Leandro office at (510) 670-2800 or their Chico facility at (888) 425-2737. CA

California Asphalt Magazine • 2017 Quality Issue

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4. Intelligent compaction can measure the number of passes, mat temperatures for paving, and stiffness values for subgrade. 5. Trimble® PCS900 Dual GNSS placer spreader control system improves paving productivity, reduces material waste, and reduces labor costs. 6. Trimble® GCS900 Universal Total Station controlled Motor Grader for finish grading to within 0.01 feet (3 millimeters).

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Networking was never so much fun at this year's CalAPA 'Day at the Races' at Del Mar The California Asphalt Pavement Association sponsored their annual ‘Day at the Races’ on July 22 at the historic Del Mar Racetrack. The Star Fiddle luxury suite at Del Mar was filled to capacity, but the good times seemed to be spilling over the balcony at this year’s event. More than 100 CalAPA members, guests, family members and others cheered, jumped, danced and otherwise carried on as much as decorum would allow at the popular event during the opening weekend of the

thoroughbred horse racing season at the seaside track. A lucky few even got to fan themselves with newly acquired $100 bills. Its one of the most popular events the association organizes; the accommodations, food, convenience and camaraderie are something you don’t want to miss. To reserve your spot for next year's event and guarantee you won't miss out on one of the industry's most popular meet-ups, contact Sophie You of CalAPA at (916) 791-5044. CA

The day’s biggest winners were Tripp White (left), Blake Isreal and Mike Murray, Vulcan.

Steve Cota, Patriot Risk & Russell Snyder, Executive Insurance Services (left) and his Director, CalAPA (left) with Don wife Ruthie both won big. Daley III, CCA/DIII Transport.

Chris (left), Rebecca and Olivia Sparks, California Commercial Asphalt.

Sarah (left) and Taylor Schmidt, World Oil Corporation.

Austin Miller (hat) of World Oil with his daughters.

Leanne Szablewski (left), Jackie Allen, Herrmann Equipment, Michelle Roper, Crystal Howard, Enviromine and Kerry Hoover, CMS.

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The Daley boys at CalAPA’s ‘Day at the Races’ on July 22, 2017.

California Asphalt Magazine • 2017 Quality Issue


Standing fourth from the left, Jess Libsack from Ramona Paving and Eric Whitford, went down to the winner's circle to congratulate the winner of the CalAPA sponsored race.

Brandon Milar (left) and Russell Snyder, CalAPA.

Helena (front) and Eric Parker, California Commercial Asphalt.

Monique (left) and Frank Vasquez, Frank & Son Paving.

Steve (left) and Jennie Betting Attendant (left) and Concannon, Pavement Recycling Brian Hoover of Construction Marketing Services, LLC.

Amber (left) and Mike Hinson, Roadtec.

Mandy Koehl (left), Linda Caton and Cheyenne Gould, California Commercial Asphalt.

Janet (left) and Eric Nielson, Telfer Pavements.

Jackie Allen (left), Mike Allen, Herrmann Equipment with Andrea and Walt Weishaar Griffith Co.

Vulcan Materials group; Mike Murray (left), Blake Israel, Tripp White, Jay Carter, Jen Merritt and Ryan Merritt.

Sarah Sokol (left) and Devan Hoskins, California Commercial Asphalt.

Derek Miller (left), Amber Miller, Melanie Liebl and Jeff Liebl, Quinn Companies.

Mike Hinson, Roadtec (left), Race number 6 at CalAPA’s ‘Day Shawn Hutchings, Roadtec, Mike at the Races’ on July 22, 2017. Glenn, ATP Paving, Mike Allen, Herrmann Equipment and Cliff Szablewski, RJ Noble.

California Asphalt Magazine • 2017 Quality Issue

Sue Liston (front) Larry Liston, and Dana Baltazar, California Commercial Asphalt.

Tracy (left), KC and Andrea Zubek, DeSilva Gates.

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NEW MEMBERS OF CalAPA SITECH NORCAL

PRECISION COLD PLANING, INC.

Chris Mata, Sales Engineer Heavy Civil Construction cmata@sitechnorcal.com

Rob Rozhon, President rrozhon@precisioncoldplaning.com

833 Montague Ave. San Leandro, CA 94577 P: 510.670.2800 www.sitechnorcal.com

Mike Mayer, Sales Engineer Aggregate Solutions mgmayer@sitechnorcal.com Tom King, Sales Engineer Heavy Civil Construction tmking@sitechnorcal.com

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13552 Calimesa Blvd. Yucaipa, CA 92399 P: 909.446.0010 www.precisioncoldplaning.com

Eric Kizziar, Estimator ekizziar@precisioncoldplaninginc.com Gordon Yocham, Field Superintendent ggyocham@precisioncoldplaning.com Dave Johnsen, Sales djohnsen@precisioncoldplaning.com

California Asphalt Magazine • 2017 Quality Issue


CALENDAR UPDATE ANNUAL GOLF TOURNAMENT Date: Thursday, September 21, 2017 Pacific Palms Resort 1 Industry Hills Pkwy, City of Industry

FALL CONFERENCE Date: October 25 & 26, 2017 Doubletree Hotel 2001 Point West Way, Sacramento

ANNUAL DINNER Thursday, January 18, 2018 Jonathan Club 545 S. Figueroa St., Los Angeles, CA 90071 Meeting dates are subject to change. Watch the weekly Asphalt Insider newsletter for meeting updates or call CalAPA at (866) 498-0761 to confirm meeting date and location.

California Asphalt Magazine • 2017 Quality Issue

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