State of the Asphalt Industry
FDR, 5 Inches HMA Saves County Money, Materials
Cool Your City SPEC ASPHALT
Clean Transfer Point Store WMA Elements Compact Safety Edge APAC Preps 2013 Project Keating Upgrades for Market December 2012
Departments Letter from the Editor 5 Concrete Laced with Mad Cow Disease Spurs Second Zombie Apocalypse Around the Globe 6
Safety Spotlight 8 Fix Leaks Immediately by Cliff Mansfield
S 26 State of the Climate Keep Our Cities Cool with Asphalt By Dr. Howard Marks
Mix It Up 10 How to Compact High RAP, Sloped Shoulders From AsphaltPro Staff and National Center for Asphalt Technology
30 API Takes on Full Recycling Steuben County FDR project calls for 17,344 tons of Superpave with RAP By Sandy Lender 36 Stop Rolling There By Sandy Lender
Producer Profile 14 Midsouth Sets Stage for I-20 Project By AsphaltPro Staff
S 42 The State of Upgrading P.J. Keating retrofits plant for future products By Astec Industries
Project Management 22 Manage Temperature By T.J. Young
S 46 The State of Silica Dust Shave Your Face and Other Methods of Frac Sand Dust Control By Mark Kestner
Equipment Gallery 60 Take Eye Safety Seriously Here’s How It Works 66 D&H Equipment’s Auto Loader 68 PHCo’s Hot Oil Heat Transfer Unit Resource Directory 73
S 50 State of Storage Where Does WMA Equipment Go? By AsphaltPro Staff 56 Pink Power Paving By John Ball
Last Cut 74 Petroleum Around the Globe By AsphaltPro Staff
S 59 State of the Competition MIRIAM Poses Logical Response for CSH Report By AsphaltPro Staff 64 International Smoothness By AsphaltPro Staff
State of the Asphalt Industry
FDR, 5 Inches HMA
Saves County Money, Materials
Cool Your City SPEC ASPHALT
Clean Transfer Point Store WMA Elements Compact Safety Edge APAC Preps 2013 Project Keating Upgrades for Market DECEMBER 2012
On The Cover…This ADM plant produced about 160 TPH of Superpave with RAP for the Indiana CR 800S project. See related article on page 30. Photo courtesy of Tom Johnson of API Construction.
editor's note December 2012 • Vol. 6 No. 3
Concrete Laced with Mad Cow Disease Spurs Second Zombie Apocalypse 2001 Corporate Place Columbia, MO 65202 573-499-1830 • 573-499-1831 www.theasphaltpro.com publisher
Chris Harrison associate publisher
Sally Shoemaker firstname.lastname@example.org (573) 499-1830 x1008 editor
Sandy Lender email@example.com (239) 272-8613 Art Director
Kristin Branscom operations/circulation manager
Cindy Sheridan business manager
Renea Sapp AsphaltPro is published 10 times per year: January, February, March, April, May, June/July, August/September, October, November and December by The Business Times Company, 2001 Corporate Place, Columbia, MO 65202 Writers expressing views in AsphaltPro Magazine or on the AsphaltPro website are professionals with sound, professional advice. Views expressed herein are not necessarily the same as the views of AsphaltPro or Business Times Company staff, thus producers/contractors are still encouraged to use best practices when implementing new advice. Subscription Policy: Individual subscriptions are available without charge in the United Sates, Canada and Mexico to qualified individuals. One year subscription to non-qualifying Individuals: United States $90, Canada and Mexico $125.00. For the international digital edition, visit theasphaltpro.com/subscribe-2. Single copies available $17 each.
Here’s another editorial note where I should remind you that I have a side career in fiction writing. I’ve read a bizarre yet true report from the BBC that states researchers from Delft Technical University in the Netherlands have put limestone-producing bacteria into concrete mixes. The researchers put harmless, dormant bacteria and food for it—specifically calcium lactate—into concrete mixes to produce self-healing walls and walkways. Nevermind that scientists anthropomorphize chemical compositions; they want to test this “healing ability” outdoors where the general public will have access to it and turn into the walking dead. The obvious question is why do we think it’s a positive thing to put bacterial spores and their food in a wall and expose this to rainwater? You see, the spores sit around doing nothing, even in the presence of the milk component they need to eat, until rainwater works its way into the cracks in the concrete. On one hand, I offer kudos to the researchers for pointing out that everybody knows concrete cracks. Everybody knows that rainwater trickles into the cracks and rusts the rebar and other strengthening materials used in concrete construction until the materials expand and cause bigger cracks. It turns out, if you spend a bunch of money on Bacillus granules and food, and on a pleasing coating to strengthen the particles to survive the mixing process you can get concrete that still cracks. But when it cracks, the rainwater goes inside the crack to rouse the Bacillus to eat and have a reaction that seals the crack. Isn’t that reaction called crapping? And what happens when the research team has the improved system it wants to have in six months and tries it in a sunny location? Will warmer temperatures sour the calcium lactate? Will the rainwater draining through cracks of sleepy bacteria granules wash out the soured milk? Will Bacillus raw sewage, rusted rebar and sour calcium lactate combine in a noxious waste-water nightmare that sends troops of poisoned zombies to kill us all? Here’s my beef with sprinkling granules of bacteria and nutrient-rich bacteria food into pavements: It’s bacteria. Yes, there are good bacteria like those movie stars want us to get out of yogurt. Then there are bad bacteria that damage brain tissue. I have a friend who contracted an infection thanks to bacteria after surgery a couple years ago. It’s insane what a person has to go through to wipe some of these pathogens from an environment. We’ve “engineered” antibiotic-resistant superbugs that conquer and survive the everyday medicines and cleansers we toss at them so flippantly. Now we want to put some of the so-called good bacteria in our walls? And feed them? I feel a bad science fiction movie coming on. If the materials engineers at the various state DOTs (I’m pointing at you Indiana and Colorado) can hand out alternative bid projects to concrete, then what kind of chance do we citizens have against bad bacterial decisions? All they need to hear is how this concrete will heal itself when the bacteria starts crapping and they’ll overlook the fact that the process of adding coated calcium lactate and microbes to concrete production adds 50 percent more to the initial cost. But who cares about initial cost when the pavement will heal itself after the zombies have eaten all of us? After all that vitriol, I really must say I don’t believe materials engineers are crazy enough to blindly add microbes—good or otherwise—to porches, playgrounds or roadways. At this beautiful time of year when much of mankind is celebrating one holiday or another, I wish materials engineers and science fiction movie buffs a lovely season. May we all have a Merry Christmas, happy holidays and a prosperous, zombie-free New Year. Stay Safe,
Sandy Lender www.theasphaltpro.com | ASPHALT PRO 5
around the globe
Industry News and Happenings from Around the World United States • America’s youth takes up the issue of transportation funding in 2013. “Should the federal government substantially increase transportation infrastructure investment in the United States?” will be the question debated in schools as part of the 2013 Urban Debate National Championship Tournament. The American Road & Transportation Builders Association (ARTBA) will lend its support by becoming a major sponsor of the tournament, which takes place April 18 through 21 in the nation’s capital and includes events at Georgetown University. Source: ARTBA • For up-to-the-minute info and updates that impact the asphalt industry, follow http://twitter.com/AsphaltPro.
in the CDOT documents section. The six CDOT engineering regions should have 36 different projects in 2013. • Everyone can register for the 40th annual Rocky Mountain Asphalt Conference and Equipment Show taking place Feb. 27 through March 1, 2013, at the Crown Plaza Denver International Airport. The theme this year is “Asphalt Pavement: A Life Cycle of Performance.” The conference staff has planned 28 breakout sessions and 21 educational sessions on materials, maintenance and equipment. There’ll be outdoor demonstrations, a plant tour and a lab tour in addition to 60,000 square feet of tradeshow vendors and activities. Visit www.rmaces. org for more information.
Maryland Arizona It’s not too early to plan for the National Asphalt Pavement Association (NAPA) 58th annual meeting at The Phoenician in Scottsdale this Feb. 10 through 13, 2013. Visit www.asphaltpavement.org for full meeting details and sponsorship opportunities.
California Although new technology retrofits for offroad diesel construction equipment won’t be widely available until 2014, the California Air Resources Board (CARB) has proposed the U.S. Environmental Protection Agency (EPA) require them now in the state. The Southern California Contractor’s Association and the United Contractors have warned the EPA that the CARB regulations will disrupt project delivery, among other negative impacts. Source: ARTBA
Colorado • Contractors in Colorado can check out the Colorado DOT’s project list for its $132.77 million FY2013 surface treatment program at www.co-asphalt.com 6 december 2012
The newly formed Pavement Economics Committee (PEC) has formed its six task groups and four of them had held face-to-face meetings as of press time. Former National Asphalt Pavement Association (NAPA) Ron White of Superior Paving Corp. is chairing the PEC. As of Nov. 1, twenty-two state associations had pledged financial support for the committee that will develop strategies to grow the market for asphalt pavements and counter the cement/concrete industry’s assault on asphalt’s share of the pavement market. For more information about the PEC, contact NAPA President Mike Acott at (888) 468-6499 or firstname.lastname@example.org. Source: NAPA
Oklahoma Smico—Symons Vibratory Equipment, announces the new facility that had sustained storm damage in May has been restored. “All is cleaned up and ready to go.” If you’d like to attend an open house at the new location in Oklahoma City to check out their sceening, feeding and vibrating conveyor applications, send a note to email@example.com or call (405) 946-1461.
Texas Have you hesitated to click on a short URL? Wonder how to make one and why? Has someone asked you to comment on his blog? You like someone’s page on facebook, but he insists that you actually don’t. Stop the madness! Social media guru and AsphaltPro editor Sandy Lender leads the workshop “Using Online Resources to Grow Your Asphalt Business” Thursday, March 21, at 7:30 a.m. during the World of Asphalt’s People Plants and Paving Training Program to be held March 19-21, 2013, in San Antonio. It’s early, but it’s packed with information on how to use social media efficiently to network and to expand your asphalt business. Visit http:// www.worldofasphalt.com/ for all your registration needs.
Washington, D.C. Did you know…under Moving Ahead for Progress in the 21st Century Act (MAP21), the Recreational Trails program was consolidated into the new Transportation Alternatives program, which also includes the old Safe Routes to Schools program and the Appalachian Highways program. The new program is to receive $1.6 billion over two years.
Fix Leaks Immediately T
he asphalt plant and surrounding yard can be a dangerous work environment. Accidents happen far too often if workers don’t pay attention to details, aren’t taught good safety practices or become complacent over time. Most accidents can be traced to the same root cause: production needs supersede common sense safety practices. Let’s take a look at one such case in the northwest of the United States. In the summer of 2011, workers at a portable drum plant in the northwest were trying to get the liquid asphalt cement (AC) to circulate. The heat transfer oil system had failed, so they were using a propane torch to heat the suction and discharge lines to the circulating pump. The shaft packing on the pump had leaked for several months, thus a large accumulation of fluid had built up on the frame around it and on the ground under it. Additionally, the liner had worn through in the dryer discharge collar and a large pool of diesel-soaked asphalt and aggregate had amassed a few feet away from the pump’s mess. When the torch ignited the asphalt under the circulat8 december 2012
by Cliff Mansfield
ing pump, the fire quickly spread to the asphalt under the dryer. In minutes, a major conflagration engulfed the area. Someone instructed the loader operator, who we’ll call Jose, to take his machine near the flames to retrieve the company’s portable welder, which was in danger of burning. Jose moved forward, but the growing flames quickly forced him to halt. Unbeknownst to Jose, a 50-year-old trucker had rushed in to help with the welder; he’d run in behind the loader. Jose backed over him and the trucker died from his injuries. This crew is fortunate not to have lost many more co-workers that day. Their terrible accidents can be traced directly to a lack of proper maintenance. If they had repaired the circulating pump and the discharge collar in a timely manner, and cleaned up the resulting messes, this accident may never have happened. The whole scenario might have been avoided if the heat transfer oil systems had been properly maintained and operated as the manufacturers intended. Even systems like the lo-density hot oil heat transfer system detailed in the Here’s How it Works department on page 68 this month that have preset features need a quick visit. The
AT LEFT: Make sure someone is assigned to perform daily maintenance checks—sometimes called “a walk-around”—at the plant to be sure no leaks are present. This hot oil circulating pump and pump motor are in pristine condition, and that’s the way you want yours to look, with a clean, material-free surface below them. Photo courtesy of Heatec. ABOVE: A fuel pump—the black box in the center of the photo—should also be checked during daily maintenance walk-arounds to ensure you have no leaks to worry about. This burner with fuel pump shows a clean, ready-to-install model. Yours won’t be that clean in the yard, of course, and if yours is larger, it will likely have a remote fuel pump with its own motor. Photo courtesy of Heatec.
plant operator may have the luxury of arriving to an already warming system at the beginning of his shift, but that doesn’t mean he can put the system out of his mind. A few minutes of repair work would cut into production time, but would have prevented the whole scenario outlined here. As mentioned above, a common thread in asphalt plant accidents is a disregard for safety issues in deference to production pressures. Asphalt plant operators often feel tremendous pressure to produce by any means possible. Unfortunately, this shifts the focus off safety and onto money without anyone realizing it’s happened. A clear-cut set of guidelines dealing with the company’s policy on safety issues should be drawn up and distributed to everyone involved with the plant. Be sure to include the paving superintendent so he or she doesn’t unknowingly exert pressure on the plant operator. Remember: Everyone wants to do a good job that the state inspector or owner/agency will approve. Sometimes employees go to great lengths to get results. To that end, conditions are overlooked that would never be overlooked or forgotten under normal circumstances. When dealing with safety issues, one must keep in mind the fact that you need to be safe all the time; you need only be careless once for tragedy to strike. Cliff Mansfield is an asphalt plant engineer and a freelance writer specializing in asphalt plants. For more information, contact him at (541) 352-7942 or send him your question through the “Ask the Plant Expert” form on the home page at www.TheAsphaltPro.com. www.theasphaltpro.com | ASPHALT PRO 9
mix it up
How to Compact High RAP, Sloped Shoulders
From AsphaltPro Staff and National Center for Asphalt Technology
This sloped shoulder was paved with Hot-Rap more than 10 years ago. Photo courtesy of Prairie Contractors
any agency officials who are responsible for the construction and maintenance of rural roads have found themselves called upon to improve the safety of the rural roadways’ pavement edges. The officials in Calcasieu Parish, La., have experienced problems associated with unpaved shoulders. Parish Engineer Tim Conner explained one safety problem. “In the past, we typically built two to three-foot shoulders using crushed limestone,” Conner said. Over time, the unbound aggregate washes away, leaving a pavement edge drop off that poses a significant safety hazard. The problem is one AsphaltPro readers have read here before. When a driver veers off the road, a vertical pavement edge drop off may cause him to over-correct his steering in an attempt to return to the paved roadway. This can result in loss of vehicle control that can cause a severe collision. It’s a known fact by now, roadway departures are the leading cause of highway fatalities nationwide. About a decade ago, Calcasieu Parish began placing narrow, tapered, 10 december 2012
paved shoulders to help eliminate the hazardous pavement edge drop off. The agency’s spec was based on a lowcost shoulder mix known as Hot-Rap, which was first used by Prairie Contractors, Opelousas, La., on a widening and overlay project in Beauregard Parish in 1998. Originally, Hot-Rap was a blend of crushed aggregate base and sand, with an asphalt content of 2.5 percent. “Now we’re able to use 40 to 50 percent RAP in the mix,” James “Jay” Winford, president of Prairie Contractors said. “And we can incorporate a lesser quality RAP than is used in surface mixes.” Hot-Rap is manufactured at approximately 250 degrees F and is placed at widths of 1 to 4 feet, depending on project requirements, using a side spreader. Paving Superintendent Jerry Chaney has been with the company for more than 33 years and was the first to place Hot-Rap on a Louisiana DOT project, according to Prairie President Jay Winford.
“Since then, Jerry’s spearheaded efforts with Calcasieu Parish whereby this is their standard for all roads.” Chaney explained that the company uses a Blaw-Knox R195 to place the mix. “We use the road widener that has a blade on it that strikes it off,” he said. The strike-off gives the end of the slope a structured edge. While there’s no numeric density requirement, the mix is compacted to the satisfaction of the engineer using a steel wheel roller. The outside edge is tapered to match the existing slope, and some handwork is required. That’s where most contractors come up with questions. In the Northwest, placing a chip seal on a new roadway within 12 months of completion protects the unsupported edge, but not every agency can afford to go back out and put a seal on every project. Both John Ball of Top Quality Paving and Dr. Ray Brown of the National Center for Asphalt Technology (NCAT) tell contractors not to discount the paving devices. “Shearing it off is enough to seal it,” Ball said. “The safety edge is placed at a slope that makes it difficult to compact,” Brown shared. On the NCAT Test Track, paving crew members rolled it the same way that they would roll without the safety edge, he explained. “So the steel wheel roller overlaps the edge but it doesn’t really come in contact with the safety edge, which is placed with a sloped surface. It does get some compaction with the paver when placed, but very little additional compaction.” Chaney has found success getting compaction on the sloped edge with a steel wheel roller. “We put three passes with a 12-ton roller forward, back and forward again, which is sufficient for the Hot-Rap. This is fewer passes than we would use with a regular hot mix.” As Brown explained in “Stop Rolling There” on page 36, the technology of
mix it up
warm-mix asphalt mixes allows density success at lower temperatures than hot mix asphalt mixes allow. The shoulder mix Conner of Calcasieu Parish calls for may be called Hot-Rap, but that’s not an indication of high temperatures. The mix is produced at 250 degrees F, which is “hotter” than crushed aggregate that can be washed away. Of course, that doesn’t mean foremen should let roller operators wait to get on the sloped shoulder. In fact, the Safety Edge Guidance and Policy document from the Federal Highway Administration (FHWA) advises the breakdown roller gets on the edge quickly.
How to Make Hot-Rap • Crushed aggregate base sand • 2.5 percent AC • (40 to 50% from RAP) • Mix at 250oF
How to Compact the Sloped Shoulder
1. Blade the ground, preparing the shoulder with slope before paving 2. Place mat and create sloped shoulder simultaneously using a widener or other device that strikes off an edge and places a seal on the top of the mat 3. Get a 12-ton, steel wheeled roller onto the shoulder immediately behind the screed 4. Roll three passes in breakdown
12 december 2012
ABOVE LEFT: The Hot-Rap shoulders in Calcasieu Parish have a great chance of lasting for decades because the Prairie Contractors paving crews take steps to ensure they achieve good compaction on them. Photo courtesy of Prairie Contractors ABOVE: The shoulder drop off on LA 466 shows the steep pavement edge that agencies and DOTs wish to remove from rural roads to make safer surfaces for the traveling public. By placing a sloped pavement edge along such roadways, the agencies provide a smoother transition for motorists who accidentally veer off the main line and make corrections to get back into the travel lane. Photo courtesy of Prairie Contractors INSET: Here a crew places Hot-Rap shoulder material to build a sloped pavement edge. Drs. Buzz Powell and Ray Brown of NCAT suggest the best way to compact the edge is to let the widener strike off the edge and have a steel wheel roller overlap the edge. Photo courtesy of Calcasieu Parish Police Jury
“Delaying the rolling of the edge of the mat should be the last resort taken to retain the slope of the Safety EdgeSM. This becomes a decision between durability along and near the pavement edge and retaining a slope of the Safety Edge.” Because FHWA recommends the Safety Edge be at an angle of 30 degrees after rolling, contractors are concerned about displacement or lateral movement of the mix under the roller. Chaney had an answer for this as well: planning ahead. “We blade the ground out with slope before we pave,” he said. “This allows uniform thickness when paving, more control of the material and keeps the material from squeezing out too far.” The initial cost of placing Hot-Rap shoulders is greater than using crushed stone, but when high percentages of RAP are used, that additional cost can be estimated as a manufacturing cost of approximately $10 per ton. In
addition to creating a safer roadside, paving shoulders with Hot-Rap has resulted in other benefits for Calcasieu Parish. The mix is very durable, Winford said, noting that early Hot-Rap projects still look good after nearly 15 years in place. Shoulder maintenance cost is greatly reduced because the material doesn’t wash away and the placed material prevents vegetation growth. Pavement edge markings also stay cleaner due to the paved shoulder buffer. Additionally, the mix is used to provide erosion control around turnouts and drainage structures and can also be used to prevent erosion on the steep front slopes of ditches. Most importantly, paving shoulders with HotRap is saving lives, Winford said. “I think that using asphalt shoulders, especially with high quantities of RAP, is one of the best things we can do to offer our owners and public agencies a great safety enhancement.”
Midsouth Sets Stage for I-20 Project By ASPHALTPRO STAFf photos courtesy of John Ball, proprietor of Top Quality Paving, Manchester, N.H.
14 december 2012
LEFT: The Tarrant site plant features a counterflow double barrel drum where plant foreman Dennis Graham can produce mix with RAP or RAS. For the I-20 project discussed here, one of the mixes he made included PG67-22 with Evotherm. ABOVE: The Tarrant plant site features eight cold feeds and two RAP bins.
he end of this paving season sees APAC Midsouth, Birmingham, Ala., preparing for a busy 2013. One of their paving crews began in early October with simple patching and continued into November with night paving to get Interstate 20 ready for summer shutdown. Midsouth crews are no strangers to coordinating with others. From the Oldcastle company’s beginning, combining forces has been standard operating procedure. Mike Glass, production manager, said it’s hard to say which of the many plants the company owns started up first. “Midsouth is a grouped company that consists of several divisions combined. This company was APAC Southeast and APAC Gulf Coast that were consolidated into one group.” Some of the oldest plants in the group are a 1972 Barber Green batch plant and several parallel flow drum plants from 1979 to 1982. These days, the majority of the Midsouth plants feature Astec
double barrel drums, CMI plants as well as Gencor plants, which Glass said allows them to produce multiple mixes such as hot-mix asphalt (HMA), warm-mix asphalt (WMA) and cold mix (CMA) for their customers. “Different dryers are counter flow and parallel flow,” he explained. “Also, we have converted some batch plants to drum plants by adding mini drum mixers.” Of course the latest technology is on their minds these days. In the past few years, the Midsouth team has been making modifications that incorporate higher recycled asphalt pavement (RAP) and recycled asphalt shingle (RAS) use, WMA technologies, energy reductions and multiple silo configurations. An interesting strategy the Midsouth company uses with silo configuring is not to max out on capacity (tph). None of the silos in the plant family are more than 200 tons and that’s by design. www.theasphaltpro.com | ASPHALT PRO 15
“Good daily planning allows us to have mix ready for on-time delivery,” Glass said. “Some plants run three to four different mixes a day and multiple silos allow this without holding a customer up. Multiple silos reduces plant restarts.” At the Tarrant plant site, where APAC Midsouth produces mixes for the I-20 project, APAC Midsouth works with an 8-foot diameter counterflow double barrel. Eight cold feeds and two RAP bins feed into the plant and also have RAS capability there. Five 200-ton silos receive mixes and have a PM-96 drum control 16 december 2012
and a stand-alone APAC ticket system to keep production automated. For the I-20 project, APAC Midsouth makes a 424 wearing surface mix, 423 SMA binder, and a 423 SMA wearing surface mix. They incorporate PG6722 with anti-strip, PG67-22 with Evotherm and PG76-22 with polymer. Bobby Egger, the project manager for the I-20 project, said the plant’s about 30 minutes from the paving site, which is one of the busiest interstates in Alabama. It’s a stretch of I-20 in Jefferson County between Exit 140 at Leeds to I-459. Egger explained that patching began around Oct. 1.
The crew was paving at night to correct slopes and enhance safety along the roadway. When they’re done, they’ll have a 4-inch overlay of SMA and seal for the Alabama Department of Transportation so next spring, they can perform a much larger project. Starting in March, they’ll shut down one side of the interstate, detouring traffic onto interstate I-459 for March, April and May. Then the process reverses for June, July and August. He shared that the crew is responsible for its own traffic control. That means safety is set squarely on their shoulders.
LEFT: Dennis Graham uses a PM-96 drum control and stand-alone APAC ticket system to produce mix and keep customers supplied from the counterflow plant. ABOVE: Five overall keys to safety remind employees and visitors to the Tarrant Asphalt Plant that APAC Mid-South has a commitment to everyone’s health and safety on the job.
“Our safety culture has changed so the employee has responsibility for safety,” Egger said. “It’s not a dictatorship. The company doesn’t just ‘tell’ people what to do. We have safety leadership teams called SLTs that meet every month and we have T5 meetings every day before we start our jobs. We go over safety every night. Safety is No.1.” By empowering employees to be part of the safety process, the company has made them part of the commitment to safety. Oldcastle Materials Group has a Commitment to Zero Policy that began in 2010 that all divisions participate in. “If somebody comes up with a good idea, we can implement that best practice,” Egger said. “If there’s an incident, we conduct a root cause analysis of the accident. Those things have gotten the employees more involved in safety and the safety culture.”
Staying on top of safety counts for every project and every day, especially as they lead up to bigger tasks that put them on a deadline. “Next year is the big part of the I-20 job,” John Ball said. He was on hand in October to assist Egger’s crew with back to basics training. “They’ll have to remove and bust up concrete and replace it with asphalt while under a time constraint,” Ball explained. “But they’ll have no trouble. They’ve got good equipment operators who work hard. They take the job seriously and they care.” Ball had glowing things to say about the mechanic on the I-20 job, Tim Wright. “Tim has a real good sense of humor and is a real crafty guy. If you need something, he can put it together. He keeps the job going. These guys have some older equipment and he can run just about anything. His skills are many.”
www.theasphaltpro.com | ASPHALT PRO 17
18 december 2012
LEFT TOP: Ricky Egger (at left) is the superintendent and Bobby Egger (at right) is the paving superintendent. They’re both at the top of their game for APAC Mid-South.OPPOSITE PAGE BOTTOM LEFT: Each APAC Mid-South paving crew includes 12 to 14 members and every paving shift begins with a safety talk. Before the whole crew dispersed, Ball snapped this photo. Back, from left: Tim Wright (mechanic), Toby Huynh (paver operator), Chris Yarbrough (laborer). Front, from left: Clinton Haynes (foreman), Ricky Egger (project superintendent), Dave Ponce (roller operator), Dewey Sellers (roller operator). OPPOSITE PAGE BOTTOM RIGHT: Paver Operator Toby Huynh shows a positive attitude and professional skill.
Ball was also impressed with the paving operator on the I-20 job, Toby Huynh. “Toby’s been there five years and does a fantastic job. He keeps a nice, straight line and goes at whatever speed they need. He’s real consistent. He also listens to directions and has a great attitude. He does a great job of maintaining the paver and cleans up the end gates so they look brand new.” With good crew members who pay attention to such details as maintenance, equipment operation and the all-important safety aspect of the job, APAC Midsouth management has good reason to brag on its teams. The Tarrant asphalt plant site with the paving crews that work from it show an attitude of teamwork and commitment to collaboration for a great job. Motorists along I-20 should be proud to have this company working on their infrastructure.
www.theasphaltpro.com | ASPHALT PRO 19
20 december 2012
www.theasphaltpro.com | ASPHALT PRO 21
Manage Temperature F
ield density and mat smoothness help determine asphalt construction success and an asphalt professional’s pay. To achieve proper density and smoothness, mix temperature needs to be consistent. While material transfer vehicles (MTVs) and good paving techniques help reduce temperature inconsistencies in the field, the initial delivery temperature is established at the plant facility, not out on the road. Temperature inconsistencies originating at the plant make it difficult for the paving crew 22 december 2012
to perform, and can even set crew members up for failure. Most owner/agencies are concerned enough with temperature that they write specs for allowable temperature ranges. These temperature ranges typically establish minimums and maximums around the ideal target mix temperature. Paving success can occur anywhere inside that temperature range, but mix temperatures that rise and fall inside that range can cause problems in the paving operation.
By T.J. Young
These tolerances are typically +/25 to 30°F (or 10 to 15°C) of target design temperature. Paving and compaction experts, however, tell us that the optimum rolling and compaction pattern can vary with mix temperature shifts of only 10 to 15°F (or 5 to 8°C) so it behooves us to pay even closer attention to the shipping temperatures at the plant than specs allow. Consistency is the key. It is possible to maintain product temperatures +/-10°F (5°C) from the plant without too much difficulty.
P.J. Keating Company, Lunenburg, Mass., uses a PMII and BC4000 burner system from Astec Industries, Chattanooga, to monitor and control the plant through computer. Photo courtesy of Astec Industries
Outside of mix consistency, this is the greatest contribution the plant can make to paving success. Let’s look at how this is done and what influences production temperature. We can hold temperatures consistently on product leaving the plant and we can identify these items in this article and make them a monitoring point for your personnel in plant production. This will allow you to hold your load-out temperature within the 10°F (5°C) desirable to ensure roadway success.
Monitor “Chute to Truck” Temperature Loss
You will encounter some temperature drop between the mix temperature as it exits the chute and the final truck temperature. The question is how much. Fine mixes experience very little temperature drop relative to coarser mixes. Simply stated, base and binder mixes typically have a larger temperature drop than surface mixes and the larger the aggregate size, the greater the drop. 25-mm mixes, stone matrix asphalt (SMA) mixes, open graded friction courses (OGFC), and high recycled asphalt pavement (RAP) mixes have some of the greatest temperature drops. Temperature drops of 25°F (12°C) for these mixes are not uncommon. The reason this occurs is that the path of heat is from hot to cold. The internal centers of these aggregates are cooler than the outside surfaces as they exit the dryer, but the temperature probe in the chute is measuring the outside surface and the liquid asphalt temperature. As the mix continues up the transfer equipment and is stored in the silo for load-out the temperature stabilizes. The outer surface temperature drops and the internal aggregate temperature rises. After
it sits in the silo for a short period of time the temperature equalizes. Because the temperature probes for the plant controls are in the chute and do not measure the temperature of the mix as it is loaded into the truck, one doesn’t know this is occurring unless one takes the temperature in the truck prior to leaving the yard. On large rock mixes, high rock percentage mixes and high RAP mixes, this is highly advisable. Once the temperature drop is established, the operator can adjust his chute temperature to maintain his target final mix temperature. Handheld infrared based thermometers or infrared guns are a handy tool to have around the plant. Keeping all safety measures in mind, have a ground person use an infrared gun to take temperature of mix as it exits the chute, and then of the stored mix as it enters the truck. Have him or her feed this temperature drop information back to the plant operator. Note that vapors and steam can cause these devices to read low, so it is sometimes necessary to find the variance using both a calibrated stick thermometer from the lab and the infrared gun. Once the temperature drop for the mix is established with the assistance of the ground person, the operator can know his proper chute temperature to maintain his target truck temperature. Keep in mind most controls manufacturers include temperature sensors that will do most of this job for you, feeding the measurements into the controls system and making adjustments as your plant operator sets it to make them. Of course, no controls system gets inside the bed of the haul truck for you. Wade Collins of Pavement Technology Inc. (PTI) agreed that it wouldn’t be too difficult to affix a thermocouple to the Robotic Truck Sampling Device (RTSD) to make temperature collection easier. The RTSD already has a telescopic probe that plunges into the hump of asphalt in the back of the haul truck bed. After submerging in the middle of the load, the probe pulls back a 30- to 45-pound
sample size that is representative of the whole mix. It would also be representative of the whole mix temperature if the thermocouple reading it were insulated from the probe’s heat.
Maintaining Consistent Moisture in the Feed Stock
Feeding dry feed stock to the plant is really the responsibility of the loader operator. It’s easy to talk about keeping stockpiles dry, feeding off the solar face, paving under the stockpiles, and other management techniques to keep production rates high and drying costs low, but for the purposes of this discussion let’s focus on maintaining as consistent a level of moisture as possible. Feeding drier material at a consistent moisture level is the obvious goal. This of course, means keeping off the stockpile floor where all the moisture is, and then trying to feed from a consistent part of each stockpile. It is common to teach the loader operator to simply stay a half of a bucket off the bottom. An observant loader operator can see the moisture change as he extracts it from the stockpile as he works his way through the pile. Different levels of moisture will make the material appear to be darker (wetter) or lighter (drier). Being observant as he extracts material will help keep the feed stock going to the dryer at a consistent moisture level and help regulate final mix temperature. One of the greatest helps the loader operator can provide the operator is telling him on the radio if the stockpile moisture changes. This gives the plant operator a heads up that his burner position will need adjustment in the near future to maintain his target temperature. One of the biggest complaints around the plant is loader operators feeding wet material into the plant causing the mix temperature to dive. This can be avoided by teaching loader operators to move sloppy, wet material to the side of the stockpile to let www.theasphaltpro.com | ASPHALT PRO 23
At the Westport location of P. Flanigan and Sons (PFS), Baltimore, Md., team members look over controls of the Generation3 automation from Libra Systems, Inc., Harleysville, Pa. Controls systems today can monitor and report temperatures around the plant, making the job of the ground personnel less hectic and the job of the plant operator more precise. Photo courtesy of Kelly Heck, InfoPathways, Inc., Westminster, Md.
it dry rather than simply feeding it to the plant. Also, when fresh wet material has just arrived into the yard, treat it like produce at the grocery store— stock it in back. It may be more convenient to feed the new arrival directly into the plant, but the best practice is to take a few additional loader movements and relocate it to a proper part of the stockpile. Remember that final field density, smoothness and a paving bonus may be at stake. The loader operator is a long way from the paving operation, but is a critical part of the paving success.
Hold a Consistent Production Rate
With most plants there is about a fourto five-minute delay from the cold 24 december 2012
feed bins to the exit of the drum. Raising or lowering the production rate forces a change of burner position because there is a different quantity of material going through the drying drum. It is difficult for the automatic temperature adjustment algorithm in the burner controls to respond with precision to these changes. In fact, some plant operators will run their burner controls in manual for this reason. Making small changes in production rate helps greatly, whether you are using the automatic burner control feature or you are adjusting it manually, because small changes in burner position are required. Large swings in production rates will likely result in wider variations in final product temperature until the new
burner setting is arrived at through taking a new set of temperatures. If we accept that maintaining temperature consistency is a primary goal of production for paving success, then making small changes in production rate is logical. “Ramping up” and “ramping down” the production rate (5-10 tph change every 5-10 minutes) has other benefits, like ensuring consistent fines content in the mix because it takes a fairly long time for the fines to enter and be returned from the baghouse, but it also helps greatly in maintaining a consistent final mix temperature. Paying close attention to these factors of mix production that affect mix temperature will allow the plant to contribute greatly to the success of the paving crew. ”
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Asphalt Plant Products
GTB-4840AWS Cedarapids Portable Drum: Nominal, 88" Diameter x 30' long RAP entry • Collar • Triple-axle portability • Leveling jacks and support pads • 100 HP drive motor • Slinger type, feeder conveyor with a 5 HP, 30" wide x 14' long belt, rated at 600 TPH • Cedarapids 75 million BTU burner, Number CRX -16 for diesel fuel • Cradle chain drive
GTB-4840BWS Cedarapids Portable Pulsejet Baghouse: Model 11060P-13 • Triple-Axle portability, with leveling jacks and landing pods • Portability measurements are; nominally 39 ft long x 11ft-8in wide x 10ft tall • The Baghouse reportedly has a nominal capacity of 50,000-55,000 CFM • Bottom mounted, drag slat type dust removal with 7.5 HP drive • Twin 100 HP Exhaust Fan motors
GTB-4840EWS Cedarapids Self-Erect Silo: Portable Self Erect, 70 ton
capacity • Triple-Axle portability with built-in Gooseneck, Landing Gear and etc. • Champion, piston type 10 HP Air Compressor • Slats are 6" x 24" bolt-on • Single strand, 6" pitch, Slat Roller Chain in good condition • Easily accessed, Slat Chain Tail take-up assemblies • Heavy Duty, shaft mounted reducer drive assembly • On-board hydraulic elevation package with cable assist
GTB-4841BWS CMI 30,000 Gallon Portable Liquid AC Tank: Direct Fired with a Power Flame brand Diesel Burner • Gooseneck of trailer has a built-in diesel storage tank • Equipped with a 15 HP loading/unloading pump • Equipped with an overflow pipe in bottom of trailer frame • Landing jacks and blocking pads, for stabilizing the tank • Inside of tank looks good, oil has been drained • Equipped with a pump metering skid on rear of unit • Stairs to top of tank to access lid of tank for inspection • Tandem axle portability • 66' long X 10'-7" wide
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State of the climate
ow that we’re into December, many of us may have already forgotten just how warm the summer of 2012 was. Indeed, it was one of the hottest on record in the United States. People in cities may have found it even more uncomfortable, as the urban heat island (UHI) effect is accentuated during hotter summers. This brings new urgency to the question of how cities’ infrastructure contributes to the heat. The UHI effect makes a metropolitan area significantly warmer than the surrounding rural areas. The main cause is modification of the land surface by urban development, which retains heat. One Clemson University researcher describes the cause of UHI as “the impacts from the close proximity of construction materials in buildings, pavements, and other infrastructure components combined together with the lack of vegetation in cities [leading] to mass heat buildup and slow release periods, which results in heat storage.” UHI was first identi¬fied in the early 1800s—long before either asphalt or concrete pavements were commonly used. Researchers today investigate how designing the appropriate infrastructure, including pavements, can help decrease urban heat and the energy required to cool buildings. Both highly reflective pavements and dark pavements can be hot— and both can be cool (See Figure 1). One difference, however, is that dark pavements can absorb solar radiation instead of reflecting it back into buildings. Although the color of a pavement is one factor that may affect the surface temperature, other pavement characteristics such as structural design, thickness and porosity all play a much larger role than color in influencing pavement surface temperature and UHI impact. For example, Clemson University researchers recently documented that permeable pavements, both concrete and asphalt, “released stored heat energy in them faster than the conventional pavement [counterparts], allowing for less buildup of solar energy in the material. . . . [and] 26 december 2012
allowing for an environment more like a rural or natural setting to exist in an urban area. This leads to cooler pavement temperatures, and a potentially smaller impact of the pavement on the area’s UHI, thus lowering the impact of the built-up materials on the local environment, mitigating human health, ecological health, and economic impact for a community.” In addition, researchers are just beginning to understand that the temperature on the surface of a pavement has little to no impact on air temperature a few feet above the pavement; nor does surface temperature increase the amount of energy required to cool the adjacent buildings. In fact, recent studies have found that reflective pavements can redirect ground-level radiation back into buildings, heating them up. An article in The Atlantic Cities reported that, “According to new research out of Arizona State University (ASU), efforts to [increase] the reflectance of Arizona’s cities by
Recent studies have found that reflective pavements can redirect ground-level radiation back into buildings, heating them up. [for example] painting roofs white may be reducing rainfall across the state.” ASU researchers found that highly reflective surfaces may reduce evapotranspiration, which is the amount of water evaporating back into the air. This corroborates what the Clemson researchers found: that permeable pavements help cool down air temperatures, increasing evapotranspiration to mimic what happens in nature. Similarly, scientists at Stanford University have recently posited that merely increasing white surfaces may actually heat up the atmosphere, increasing global warming. The Stanford study emphasizes that just painting infrastructure white oversimplifies a complex phenomenon, potentially causing unintended consequences.
Interestingly, some researchers are also looking at ways to harness a pavement’s heat sink, redirecting that energy for other purposes. And because asphalt pavements don’t reflect solar radiation back into adjacent buildings, these are the pavements of choice for harnessing heat sink energy. The science of urban heat islands is complex and should not be oversimplified. Assuming that a pavement’s color determines its contribution to the urban heat island does little to further an accurate and valid understanding of how infrastructure (including pavements) can help cool down our cities. Howard Marks is the Vice President for Environment, Health, and Safety at the National Asphalt Pavement Association. www.theasphaltpro.com | ASPHALT PRO 27
API Takes on Full Recycling
Steuben County FDR project calls for 17,344 tons of Superpave with RAP By Sandy Lender
ounty Road 800S in Steuben County had seen better days. Anthony Jarem, vice president of Soil and Materials Engineers, Inc., (SME), Kirtland, Ohio, explained that the road’s original aggregate base was a bank-run, rounded material that didn’t have a good, angular interlock. He said the surface’s last preservation treatment was about 10 or 12 years 30 december 2012
ago, but that repair hadn’t addressed the underlying problem of swampy ground and peat deposits that don’t offer a good sub-base. According to Mark Cox, regional manager for The Klink Group, things were only going to get worse. The average daily traffic (ADT) on the 4.5-mile stretch of roadway was between 2,000 and 4,000 with 15 percent of that truck
traffic. “The ADT is estimated to increase to 5,000 in the next five years with the truck count increasing to 30 to 40 percent due to the eastbound traffic from the new Family Dollar distribution center and the growth of Hamilton’s industrial park,” Cox reported. It was time to address the problems of the existing pavement, which Cox reported had an estimated 40 to
API Construction’s primary plant is the ADM Milemaker 275 in Huntertown. It has two 200-ton capacity silos and a higher production capacity than their plant in Angola. It’s located about 30 minutes from the CR 800S project.
45 percent failure in the sub-base and asphalt layer. According to his report, CR 800S had major rutting in the pavement and edge failures one can see in the image (at left). Steuben County officials looked at new construction estimates in the ballpark of $5.5 million but Cox said engineers estimated a full depth reclamation (FDR) with hot mix asphalt
(HMA) paving could come in around $2.3 million. API Construction Corporation, LaOtto, Ind., won the bid at a little more than $1.3 million, saving the county 75 percent in funds over new construction and using in-place materials. Here’s how they did it. “This project is unique in the fact that it used a FDR construction process instead of the conventional pavement
removal and replacement,” Tom Johnson said. He’s an estimator and project manager as well as the quality control (QC) representative for API Construction. “This construction process is less expensive, has a much shorter construction window, minimizes the impact to the traveling public, and is greener due to the reclaiming of the existing pavement section requiring less equipment and therefore emissions, and virtually no spoils or waste materials to dispose of.” Johnson called the job “recycling on a massive scale” with good reason. First, SME designed the FDR process for the road and the subcontractor The Klink Group came in to work on the FDR in place. “Soil and Materials Engineers performed the initial soil borings for the evaluation process for the pavement design, as well as the in-place sampling and testing of the FDR for proper cement content, water-cement ratio, density and till depth verification,” Johnson said. “The Klink Group not only performed the FDR construction process, but placed the seal coat material and hauled asphalt for us on the high production days.” SME’s Jarem said the county already owned the materials in the roadway, which presented a cost savings right off the bat. The Klink Group merely had to pulverize—Aug. 1 through 3—and mix those materials with some chemical additives, which they began Aug. 6, to enhance the road base’s properties. “Although API Construction did the fine grading and final compaction of the FDR, the actual pulverization, cement till and initial sheep-foot rolling operations were completed by The Klink Group,” Johnson said. Once the FDR section was built, API Construction paving crews had to wait at least five calendar days for it to cure before they sprayed a tack coat at a rate of approximately 0.03 gallons per square yard. Starting Monday, Aug. 13, they placed the HMA base—an INDOT Type B 19-mm Superpave mix— 3.5 inches deep. The base mix was designed with a PG64-22 binder in which API incorporated 15 percent RAP. Between the base and surface courses, they sprayed another tack coat at 0.03 gallons per square yard. The www.theasphaltpro.com | ASPHALT PRO 31
Left: The east limit of County Road 800S after the full depth reclamation and hot mix asphalt paving project shows a smooth finished surface for Steuben County’s motorists. Potholes and cracks are a thing of the past now that a stable base is covered by Superpave. Above: Mark Cox, the regional manager for The Klink Group reported that the existing surface of CR 800S had patches, potholes, deep ruts, drainage issues and edge failures, which one can see in this before picture. Opposite Page: The API Construction crew sprayed a tack coat atop the base course before placing 1.5 inches of surface course. They used the Blaw-Knox PF 3172 to place a Superpave mix with 25 percent RAP. Density averaged 92.6 percent for the 9.5-mm surface mix.
surface course was an INDOT Type B 9.5-mm Superpave mix placed at 1.5 inches. It also used the PG64-22 binder, but incorporated 25 percent RAP. To get a smooth surface, Johnson credits HMA Field Superintendent Kary Benson and Scott Fenstermaker from API’s testing department for working closely together to keep the project flowing. “Between these two individuals and their communication and cooperation, we were able to produce a consistent quality mix that not only achieved very good test results, but also performed well on the lay-down end without segregation, tearing, stripping, etcetera that can oftentimes occur. We also achieved production rates that were expected.” The crew ran the plant at an average of approximately 160 tons per hour (TPH). The paving crew used a Blaw-Knox PF 3172 paver with a material management kit and a ski modified with a mat-reference system to place 17,344 tons along nine lane miles in 10 32 december 2012
www.theasphaltpro.com | ASPHALT PRO 33
Above TOP: Engineers at Soil and Materials Engineers, Inc., designed a full depth reclamation process for the CR 800S project. The team from The Klink Group pulverized the existing roadway, and then reclaimed it with chemicals churned in with a WR2400 from Wirtgen. API Construction workers rolled the reclaimed surface and gave it five calendar days to cure before hot mix paving began. At Left: API Construction’s crew sprayed a tack coat atop the reclaimed and cured surface at a rate of about 0.03 gallons per square yard. Then the paving crew used a Blaw-Knox PF 3172 paver to place 3.5 inches of Superpave with 15 percent RAP for the base course. They used a Bomag BW266, an Ingersoll-Rand DD90 and a Volvo DD-112 to get compaction behind the screed. Density averaged 92.4 percent for the 19-mm base.
days. They used a Bomag BW266, an Ingersoll-Rand DD90 and a Volvo DD112 to get densities that they monitored in the field with a TransTech PQI and in the lab with core samples. Overall, the density results averaged 92.4 percent for the 19-mm base and 92.6 percent for the 9.5-mm surface. “The [finished] typical cross-section pavement design for CR 800S consisted of 1.5 inches of HMA 9.5-mm surface on 3.5-inches of HMA 19-mm base, which were placed on 16 inches of full depth reclamation…thus having an overall thickness of 22 inches,” Johnson explained. Cox explained how the pavement thickness was reduced overall. “If you look at a mechanical empirical value 34 december 2012
applied to the FDR section using a conservative structural co-efficient value of 0.2 per inch, we provided an equivalent new HMA value of 9 inches plus 5 inches of new HMA, which equals a cross-section equal to 14 inches of new HMA.” To complete so much work in such short order, it takes cooperation. “I can’t say enough about how fortunate we were as a prime contractor to have a great group of subcontractors such as Mark Cox, Jane Cox and Robert Creamer of The Klink Group; John and Karen Haan for signs; and Greg Lowe of The Airmarking Company for the pavement markings, which were all cooperative, knowledgeable and very timely
with our set construction sequence of operations and schedule. “Lastly, hats off to the Steuben County Commissioners Ron Smith, James Crowl and Loretta Smart for their timely assistance and guidance. Steuben County’s Highway Superintendent Ken Penick championed the idea by allowing a ½-mile FDR test project in 2011. And a very special thanks to Ken Herceg, Brian Thomasen and Adam Bowden of Ken Herceg & Associates for their quality design, project coordination, on-site inspection, engineering and for being such a valuable asset to the project and its success. The CR 800S FDR and HMA paving project is something everyone can and will be proud of for many years to come.”
www.theasphaltpro.com | ASPHALT PRO 35
Stop Rolling There By Sandy Lender
t a conference many years ago, a gentleman at one table asked the members of the small group at what temperature they advised their roller operators get off the mat. The general consensus was that mat temperatures below 170 or 180 degrees F were too cool to allow the equipment to achieve additional density. That was a time before the popularity of warm mixes. Now the question of when to start or stop compactive effort is more complex. Everyone from roller manufacturers to paving consultants have had difficulty answering the question over the years unless the contractor could first specify whether or not the mix incorporated Superpave methodology, the mat was laid beneath overly shaded areas, the base was stable enough to support the weight and force, etcetera. Tim Murphy of Murphy Pavement 38 december 2012
Technology, Inc., Chicago, explained that the mat temperature at which you take the roller off should be determined on a job by job, mix by mix, base by base, and temperature by temperature basis. He gave some specifics. “For example, if the temperature is summer-like, the mix is 300 degrees and you have plenty of thickness versus the maximum aggregate particle size, then there should be no problem,” Murphy suggested. The thickness he prefers is three times the maximum aggregate particle size. “If the base is soft and unable to hold the roller, then maximum achievable density will occur at a significantly higher temperature, and most likely will be accomplished by the use of a substantial amount of static, not vibratory, compaction,” Murphy continued. “With standard paving—solid base, good weather, reasonable thicknesses—then
ABOVE: The BW190 AD serves in the breakdown position with another Bomag roller immediately behind in the intermediate position. Make sure crew members follow established rolling patterns faithfully to achieve proper density on WMA projects, just as they would on a HMA project. Photo courtesy of Bomag Americas
the minimum compaction temperature of the asphalt is generally 180 degrees F and above, internal temperature. Below that temperature, the asphalt viscosity is such that we begin to crack aggregates and fracture the binder matrix. Neither is a good outcome.” There you have some basic caveats for taking the finish roller off when the mat temperature is 180 degrees—if you’re working with a hot mix asphalt (HMA). With warm-mix asphalt (WMA) mixes, paving foremen found the temperature immediately behind the screed equal to the intermediate rolling
zone of the typical HMA mat. They sought new rolling patterns. As luck would have it, the same principles of compaction apply when rolling WMA; equipment operators happen to have a new technology in the mat helping out. Chuck Deahl, formerly of Bomag Americas, reminded readers that the temperature of a mix determines its workability. Another stable principle is the more coarse the mix, the more quickly it will cool. The more variables the mat encounters—such as those Murphy listed above—the less time the roller operators will have to achieve density. Dr. Ray Brown, director emeritus at the National Center for Asphalt Technology (NCAT), said contractors should be rolling WMA mats the same way they rolled HMA mats with success. “We’re rolling it the same way we roll HMA and finding it easier to compact,” Brown said. “The warm-mix technology is making it workable at the lower temperatures.” There’s the crux of the matter for achieving density with WMA mixes. The technology, whether foamed or additive-based, changes the mix in such a way that temperature isn’t the same dictating factor it is in HMA compaction success. A temperature of 230 degrees F immediately behind the screed allows the breakdown roller to seal up the majority of density with a WMA mix the way 320+ did for HMA mix. Mat temperatures dip from there, but at a slower rate than they do when beginning at a high level thanks to physics. The lower temperatures don’t pose the threat to aggregate or binder matrix integrity that lower HMA temperatures do thanks to asphalt entrainment in WMA technology. Foremen will see the static finish roller achieving density at temperatures as low as 140 or 150 degrees F if they’re working on a WMA mat. “If you took regular hot mix and tried to roll it at these temperatures, you would not succeed,” Brown said. Due to the WMA technology, the cooler internal temperatures allow the contractor to achieve density with WMA mats. Depending on the factors Murphy listed above, contractors may be able to remove a roller from the compaction train and still achieve specified 40 december 2012
This team member from Grace Pacific Company checks the rolling pattern’s success with a Troxler density gauge. Photo courtesy of John Ball, Top Quality Paving
densities. Readers might think Deahl and others in the equipment sales end of the industry would be pounding the drums of status quo and encouraging contractors to keep three to four rollers in every rolling pattern, but Deahl shared that there are times when the breakdown and finish rollers can achieve density on a WMA mat without additional help. “Warm mix has definitely changed the parameters,” John Ball of Top Quality Paving, Manchester, N.H., said. Ball is another who advised contractors use caution when deciding to remove or add a roller to the compaction train. While some aspects of the train have gotten easier, he said the crew still has to be sharp. That means using the right equipment and being consistent. “We used to have to seal the mat up while it was hot,” Ball said. “We used to have a 300-foot or so rolling zone behind the screed. With WMA, you still get on right behind the screed to get the air voids out of it. Get on it more quickly and be more consistent with your established rolling pattern. You don’t have as long of a rolling zone
now. You stay within 250 feet of the screed instead of 300.” Even though Ball stressed going for density quickly and in a consistent, methodical manner, he also shared good news for moving quickly. “The WMA mat doesn’t cut up as much when you make a stop. It doesn’t bow up on you or cut in on you the way the very hot mat used to.” No matter what type of mix or mat you wish to compact, success depends on adhering to best practices. Murphy and Ball both tell their clients to pre-heat all of the paving and compaction equipment prior to start-up. Most readers know it’s wise to cover loads and haul them to the site in insulated beds, whether or not working with a WMA or a fine mix that holds its temperature well. Finally, make sure the breakdown roller—and the intermediate roller—gets on the mat as close behind the screed as possible to seal up air voids and gain as much compaction as possible in the first few passes, whether you’re working with a 300-foot rolling zone or a 250-foot rolling zone.
www.theasphaltpro.com | ASPHALT PRO 41
The state of upgrading
P.J. Keating retrofits plant for future products F
By Astec Industries 42 december 2012
rom new affiliations to new equipment, P.J. Keating Company, Lunenburg, Mass., has prepared for new asphalt products since 1999. The company was founded in 1923 and became affiliated with Oldcastle Materials, Inc., in 1999. It then became a part of a regional collaboration with Tilcon Connecticut, Inc., becoming Oldcastle Materials New England South in 2011. Thatâ€™s when management made the move for a significant upgrade of the P.J. Keating asphalt plant in Lunenburg including new silos, reclaimed asphalt pavement (RAP) mixing capability and foamed warmmix asphalt (WMA) production capability. The company began site
A massive retrofit and upgrade positions P.J. Keating’s Lunenburg plant for future projects that include RAP and WMA.
preparation, including taking down its old plant, in 2011, according to Plant Operator Eric Morin. Astec team members came in during early spring to begin setup and by early July, the plant was online. With a full year of operation under their belts, the P.J. Keating team has good things to say about their upgrading decisions. “The main part of the retrofit was to increase storage capacity and replace old, existing silos with new, more modern silos,” Joe Marrone said. He’s the asphalt division manager of Tilcon Connecticut. He said the new silos give the asphalt producer the ability
to store more materials and to store them for longer periods of time. The Lunenburg site makes a variety of mixes, including Superpave for the state and some municipal and commercial mixes. On any given day, the plant may produce seven or eight different mixes. In accordance with Massachusetts Department of Transportation (MassDOT) regulations, they can use up to 15 percent RAP in state mixes and the plant has the ability to run up to 50 percent in commercial mixes. “Until the retrofit, this was strictly a hot mix plant, but now it has the
capability to do warm mix as well,” Marrone said. “That was another reason for the update.” P.J. Keating’s Lunenburg plant, one of the company’s five locations, had been the site of a batch plant for more than 30 years, but was updated with an Astec Double Barrel® in 1995. After performing for about 15 years, that plant had done its job. As part of the massive retrofit in 2011, Astec installed the warm mix system, a 9-foot by 47-foot Double Barrel® drum mixer, a Phoenix® Talon 125-MBTU/ hour combo gas/No.2 oil burner, a fuel pump, infrared temperature sensors www.theasphaltpro.com | ASPHALT PRO 43
for aggregate and for mix, conveyors, Continuous Mix Blending Controls with a 45-inch console, a 30,000-gallon vertical asphalt tank, and all accompanying components. The plant now has a set of six 300-ton, 14-footdiameter silos with an 800-ton New Generation Storage System. It also has three new 30,000-gallon asphalt cement (AC) tanks along with a 20,000-gallon vertical double containment fuel tank with a completely new tank farm system run by hot oil. They added other items from Heatec such as a 3-inch twin pump asphalt metering system, a 4-inch asphalt unloading pump, a 2-million BTU/hour gas/oil heater with mani44 december 2012
fold, four centrifugal hot oil pumps, and a 4-inch asphalt supply pump. “With the volumes we produce here, we were under capacity with a 1,000-ton storage system,” Morin said. “We obviously needed to upgrade. The silos were old and tired….Now, with the new warm mix system, we’re environmentally friendly, pleasing to our neighbors and keeping our costs down.” Morin said another plus about the retrofit is the Blue Smoke package on the silos, which makes the plant virtually smoke-free. With the retrofit, the plant receives virtually no complaints, according to the management. They’ve had no odor
Opposite Page: Each of the six 300ton silos is 14 feet in diameter and gives the Lunenburg plant a capacity it needed. “With the volumes we produce here, we were under capacity with a 1,000-ton storage system,” Asphalt Plant Operator Eric Morin said. “We obviously needed to upgrade.” The silo system also features a Blue Smoke package, which makes the plant virtually smoke-free. BELOW TOP: Astec and Keating team members installed the Astec Double Barrel® Green so the company has the option to run warm-mix asphalt mixes at the Lunenburg facility. “Now, with the new warm mix system, we’re environmentally friendly, pleasing to our neighbors and keeping our costs down.”—Eric Morin, Asphalt Plant Operator BELOW BOTTOM: The technologically advanced computer system housed in the control house makes operation more streamlined than past automation Asphalt Plant Operator Eric Morin has used. To acquaint employees with the new system, P.J. Keating sent a team to Astec’s Advanced Customer Schools, which are held annually. “We went from an old PM96 computer…to running a PMII and BC4000 burner system,” Morin said.
complaints since the installation last year, according to Morin. “The new system is also very quiet compared to the old one,” Morin said. “We’re 6,000 feet from residential homes and with the old system running at night, we would have complaint issues from neighbors. Now, we haven’t had a single noise complaint. And we’re running seven days a week. We have very busy days and nights like asphalt plants do. We never stop.”
Morin said new state standards are coming up, but he expects to have met or exceeded state requirements with the new Astec burner. “It’s a prototype burner,” Morin said. The technologically advanced computer system makes operation more streamlined. To acquaint employees with the new system, P.J. Keating sent a team to Astec’s Advanced Customer Schools, which are held annually. “We went from an old PM96 computer…to running a PMII and BC4000 burner system,” Morin said. “I was adept at flipping switches with the old system, but with running the plant through computer, the school was definitely a plus and a must. It makes life easier for employees. It took a little bit of time getting used to, but now I can do it with my eyes closed.” This article is used with permission from Hot-Mix Magazine, Volume 17, Number 1. www.theasphaltpro.com | ASPHALT PRO 45
the State of silica dust
Shave Your Face and Other Methods of Frac Sand Dust Control By Mark Kestner
uring the handling and processing that occurs from mine to drill site, there is opportunity for silica containing dust to impact workers’ health. Among the steps to ensure worker safety, the National Institute for Occupational Safety and Health (NIOSH) recommends shaving facial hair each day when wearing respiratory protection to ensure a proper seal to the skin. Of course there’s more to controlling exposure than good hygiene and there’s nothing funny about a respirator that doesn’t fit. Most mining operations use wet processing and don’t produce appreciable dust emissions with the exception of large storage piles that are susceptible to wind erosion. Roadways can also contribute to visible dust. Processing plants that receive raw material from the mine and that crush and screen the sand into products of various sizes and properties rely primarily on dry collection systems like baghouses and cyclones to control dust. Products are conveyed to silos and loaded into trucks using sealed pneumatic systems. Waste sand, however, is often handled in the open by conveyor and placed in an outdoor pile for disposal. At National Environmental Service Co (NESCO), we have installed water spray systems to suppress dust emissions during stacking operations. These systems use pumps operating at 200 psi and conventional spray nozzles. NESCO and companies like it have also installed misting systems at dry processing plants to control dust in areas around crushers and screens where fugitive dust originates from fine material that is dislodged from conveyors and from deposition of fines onto structural members. Mechanical action and the vibration of production equipment can cause this dust to become airborne. Because it is very diffuse it’s not easily collected by vacuum filters like baghouses. These misting systems use impingement and other types of fine nozzles to produce a very fine mist with droplets in the 50 micron size range. These cause dust particles in the air to aggregate and settle out rapidly. Misting systems of this type are relatively inexpensive depending on the size of the facility and degree of automation. Major sand-producing states, such as Wisconsin, are in the process of developing regulations to establish air quality standards for visible dust emissions as well as concentration 46 december 2012
Waste sand is often handled in the open by conveyor and placed in an outdoor pile for disposal. Fugitive dust from this type of handling can be minimized with water spray systems.
standards that must be met at the property line. Sand mining operations are also regulated by the Mine Safety and Health Administration (MSHA), which has adopted strict standards for exposure to silica containing dusts. The standard depends upon the silica content of the sand. The higher the silica content, the lower the allowed standard. Fortunately, most mining to extract sand employs wet processing so that dust emissions are minimal.
Blame it on the Wind
In addition to silica containing dust emissions from sand mining and processing, producers are also attempting to develop control measures for wind-eroded dust emissions from stockpiles as well as from unpaved and paved roadways. Wind erosion is a problem because stockpiles may often exceed 60 feet in height and cover more than an acre. While aerial spray systems and fog cannons have been proposed to control pile emissions, there are few, if any examples of their commercial use because of their high cost. Watering is the most common method of controlling road dust, but the most cost-effective way to combat road dust is to post and enforce a 10 mile per hour (mph) speed limit. Paved roads have to be flushed or vacuumed to remove silt that can become airborne by passing traffic. Wheel washes can be installed at the transition from unpaved to paved road to prevent dirt, mud and silt from tracking out and contaminating paved surface.
Drill Site Dust
Exposure to silica containing dust also occurs during handling and processing at the drill site (See Sidebar “Sources at the Drill Site”). Because the finest particulate is the most hazardous, vacuum filtration systems combined with personal protective equipment (PPE) such as respirators are the preferred methods of combating exposure to respirable dust. It’s the minus 10 micron fraction that comprises respirable dust that becomes lodged in the aveoli
www.theasphaltpro.com | ASPHALT PRO 47
Suppress With Water
Wet suppression systems, fog systems in particular, may be of some benefit in suppressing airborne dust. Fog systems are able to produce droplets in the -10 micron range that collide with respirable particulate in the air. The droplets cause the particulates to agglomerate into larger sizes that will drop out of the ambient environment. Fog systems use very high pressures—greater than 1,000 psi—to produce these very fine droplets. Fog systems work best in enclosed environments such as warehouses and transfer stations, but have also been used outdoors. Interestingly, fog systems were originally marketed for evaporative cooling so they offer the additional benefit of cooling work areas in hot weather. In this composite image, you can see the plume characteristics of an impaction-pin (a) nozzle and a swirl-jet (b) nozzle in a water spray system. The smoke-like nature of the impaction-pin nozzle is evident. The straight edge of the swirl-jet nozzle in image (b) shows the high momentum of larger droplets. This implies a larger droplet size at the edges.
Keep it Clean
Good housekeeping practices are also very important. Personnel that have to clean up spills can be exposed to dust. They should vacuum or wash down sand spills rather than try to shovel or broom them up. Most of the exposure to respirable dust occurs during clean-up when workers have to remove material from under conveyors, crushers, etc. Using best practices in these instances and other control measures mentioned throughout this article will go a long way toward ensuring worker safety around silica containing dust. Mark Kestner, Ph.D., is the president of National Environmental Service Co.
Sources at the Drill Site
Close-up of the swirl-jet and impaction-pin nozzles
of a worker’s lungs. There the dust can cause debilitating silicosis. Particulates larger than 10 microns are generally exhaled. Many of the sources of dust are mobile or intermittent, which makes it difficult to use vacuum systems. This makes a respirator program a manager’s best defense for employees’ personal protection. Industry members have found some problems with respirators, which can be uncomfortable in hot, humid weather and difficult to fit for a proper seal when the employee has facial hair. One of NIOSH’s recommendations at its website is to use “respiratory protection as an interim measure until engineering controls are implemented.” The institute suggests employers meet with an industrial hygienist to decide what type of respirator to use and to establish a comprehensive program that adheres to the Occupational Safety and Health Administration regulation found in CFR 29 1910.134. Workers using respirators must be medically cleared for their use, need to be properly trained in their use and have equipment properly fitted to them. Review the NIOSH policy on respiratory protection for crystalline silica at http://www.cdc.gov/niosh/docs/2008-140/. 48 december 2012
The following list gives an idea of where fugitive dust occurs at the well site. Be aware of these locations and look into the ways MSHA and NIOSH suggest covering them or working around them for improved worker safety. • Dust emitted from thief hatches— open ports on the top of the sand movers used to allow access into the bin (SOLUTION: use local exhaust ventilation for capture and collection. Dust collectors, a portable baghouse, the NIOSH minibaghouse assembly or other collection system can be retro-fitted over the existing thief hatch openings.) • Dust ejected and pulsed through side fill ports on the sand movers during refilling operations (SOLUTION: see mini-baghouse idea above. The use of cam-lock caps for fill ports on sand movers may soon be mandated.) • Dust generated by on-site vehicle traffic including sand trucks and crew vehicles, by the release of air brakes and by winds (SOLUTION: keep vehicle speeds to a minimum; use amended water to reduce dust generation on roads into and at the well site. Do not use well brines for dust control. Also limit the number of workers, or the time workers must spend, in areas where exposure to high concentrations of silica can occur.) • Dust released from the transfer belt under the sand movers (SOLUTION: use passive enclosures at points of dust generation. Install
stilling/staging curtains around the bottom sides of the sand movers to limit dusts released from belt operation. You can install these curtains along and at the ends of the dragon tail as well.) • Dust created as sand drops into, or is agitated in, the blender hopper and on transfer belts (SOLUTION: replace transfer belts with screw augers on sand movers. This involves Prevention-through-Design.) • Dust released from operations of transfer belts between the sand mover and the blender (SOLUTION: see screw auger idea above.) • Dust released from the top of the dragon’s tail—the end of the sand transfer belt on sand movers (SOLUTION: minimize distances between the dragon tail and T-belts and blender hoppers. Minimizing the distance that sand falls through the air can help minimize dust generation.) • For any and all exposure areas, provide worker training. Hydraulic fracturing workers should be trained on the hazards of crystalline silica and the steps they should take to limit dust generation and reduce the potential for exposure. Sources: National Institute for Occupational Safety and Health (NIOSH) and the Centers for Disease Control (CDC). Visit http:// www.cdc.gov/niosh/docs/2008-140 for more information.
State of storage
Where Does WMA Equipment Go? By AsphaltPro Staff
50 december April/May 2012
hether you work with warmmix asphalt (WMA) mixes for the safety benefits, energy savings, compactive advantages, emissions reductions, or any other good reason we could list here, you have a new technology at your disposal. With new practices come new plant components and controls. Make room for marketplace expansion with the use of WMA, but don’t start breaking new ground. Most equipment and storage tucks nicely into existing plant space so the most expansion you see is in the WMA foaming chamber itself, not in your plant footprint. It’s true that if you elect to use additives to achieve a WMA mix, you can
skip the foaming equipment required in the mechanical process of WMA production. Keep in mind that the use of WMA additives can require an injection or metering system along with pallets for storing supersacs of waxes or fibers, skids for storing barrels of product or tanks for storing blended material, etc. Don’t think of that as a deterrent, though. Any number of additive-modified asphalt cements can be delivered pre-mixed and ready to pump into the production process without taking additional storage space in your yard. Ed Myszak of PQ Corporation reminded readers to watch for additives that can be used to bump the
Opposite Page Select different tanks to hold different grades of liquid binder. Photo courtesy of Astec Industries ABOVE: Joe Musil, senior engineering fellow for Terex Roadbuilding, said the Terex warmmix system works by injecting a variable amount of water with hot asphalt cement inside the single-point mixing chamber. It injects and mixes up to 4 percent of water by mass weight of the liquid AC. The system includes a water meter that works in a closed-loop method to verify that the correct percentage of water is injected with the hot AC inside the expansion chamber. Photo courtesy of Terex Roadbuilding www.theasphaltpro.com | ASPHALT PRO 51
performance grade (PG) of an asphalt binder. If you need modified PG mix as well as non-modified, you’ll want separate storage facilities for each. Look to the tank farm for the nook where you’ll place the tank to house your new binder material. Let’s say you elect to add a foaming system to your plant for a mechanical means to achieving WMA mix. This is the obvious “equipment”
producers think of when adding warm mix capabilities, but most systems are easily attached to the incoming AC line. Typically, a device allows a water inlet and AC inlet to combine forces in a single chamber and it sits in line with the drum. Depending on the manufacturer, the method of foaming and the placement of a chamber may vary, but the equipment and the accompanying Using water, the Terex warm-mix asphalt (WMA) system requires a water line to the tank, and costs for the water source will vary depending on location and access to water. The tank includes a hi-low indicator that automatically keeps the tank filled. Photo courtesy of Terex Roadbuilding
The flow meter in the Accu Shear’s control panel meters water so the plant can run in a continuous mode when producing WMA. Photo courtesy of Stansteel
The water tote and warm-mix system of the Accu Shear slide up to a spigot that provides consistent water for WMA production. Photo courtesy of Stansteel 52 december 2012
correct proportioning. Low level interlocks provide warning or shutdown to the operator. In the same way, a water holding reservoir of at least 200 gallons is an integral portion of a properly designed system….This holding reservoir receives water flow from commercial water companies, well water or any other sources the plant may choose. This reservoir allows the plant to run in a
continuous mode without any interruption to production.” Producers can see that both mechanical and additive-based WMA technologies require equipment— thus space—to be successful. Not every new technology needs to expand the plant’s footprint, and WMA components can be tucked into available nooks and crannies easily with planning assistance from the OEM.
If you need modified PG mix as well as nonmodified, you’ll want separate storage facilities for each. Look to the tank farm for the nook where you’ll place the tank to house your new binder material. Photo courtesy of Astec Industries
water tank takes up as little space as possible. “All new Terex plants are plumbed to accept the foamed warm mix asphalt system, reducing time and costs associated with initial set-up,” Mike Rodriguez said. He’s a district manager for Terex Roadbuilding. “The system requires only the single mixing chamber (installed inline), water tank skid with tank, pump, meter and the signal from the plant controls package for operation. “Whether it’s a water line or ‘rain for rent’ system for a foamed warm mix system or storage bins and method of delivery for additives, there is going to be a required investment in infrastructure to get the product where it needs to be.” Stansteel/Hotmix Parts’ Gregg Gilpin spoke of the importance of the water holding tanks and its components. “Because water (for foaming) is an important ingredient, it must be metered, calibrated and have appropriate interlocks,” Gilpin said. “These interlocks are critical to prevent no flow or partial flow and ensure www.theasphaltpro.com | ASPHALT PRO 53
Pink Power Paving By John Ball
anagement at Virginia Paving Company, a division of The Lane Construction Corp., reach out each year to do something positive to assist the Susan G. Komen Foundation. For the year 2012, the company ordered and bought the eye-catching haul truck you see here. It’s part of the company’s Norfolk Plant fleet and part of the company’s everyday operations. Companies like Virginia Paving and Lane Construction that place an emphasis on employee health and safety make me proud to be a member of the asphalt business. It’s good to see them spread the message of health and safety beyond their employees and into the community. Thousands of motorists see this truck every day. It’s part of the company’s community service and good neighbor relations. It’s part of their “Care for People” aspect of their mission.
ABOVE: Of the more than 1,000 trucks that Lane Construction Corp. owns, this one that Virginia Paving Company ordered at the beginning of 2012 is special. It represents the division’s open commitment to helping raise awareness of breast cancer and the general health of all employees. Driver Kendra Speller takes good care of her vehicle. Regular maintenance is as important for machinery as it is for healthy employees. AT LEFT: As the date drew near, Virginia Paving crews put a sign on the truck advertising the 2012 Komen Tidewater Race for the Cure®, which took place Oct. 13 at the Virginia Beach Oceanfront. The organizers raised more than $422,000 in funds with the event. 56 december 2012
www.theasphaltpro.com | ASPHALT PRO 57
58 december 2012
State of the competition
By AsphaltPro Staff
et used to the alphabet soup. The Concrete Sustainability Hub (CSH) at the Massachusetts Institute of Technology (MIT) still seeks a way to prove concrete pavements save on vehicle fuel economy. The National Asphalt Pavement Association (NAPA) summarizes CSH’s findings in its report from April of this year, “Model Based PavementVehicle Interaction Simulation for Life Cycle Assessment of Pavements,” as ignoring important phases of a pavement’s life cycle. The CSH report specifically focuses on a pavement’s stiffness. Considering the report has taken this least important variable of a pavement’s life cycle and built a case for vehicle fuel savings upon it, further study by an impartial entity is in order—an entity not funded by the Portland Cement Association (PCA) and the National Ready Mixed Concrete Association (NRMCA). First of all, NAPA has released a paper explaining that the CSH report oversimplifies the complex relationship between a vehicle’s fuel economy and the pavement upon which it drives. NAPA also points out that CSH’s report neglected to mention how roughness plays into the decline in fuel economy. And when it comes right down to it, the modeling assumptions the CSH study made aren’t accurate for asphalt pavements; they’re inconsistent at best and biased in favor of concrete pavements. As luck would have it, researchers and scientists beyond NAPA’s experts picked up on the ethical and scientific problems with CSH’s study and findings. According to Cheryl Allen Richter in the Office of Infrastructure Research & Development for Turner-Fairbank Highway Research Center (TFHRC), the Federal Highway Administration (FHWA) has a vested interest in a research project called Models for rolling resistance In Road Infrastructure Asset Management systems (MIRIAM).
According to Richter’s presentation, 12 participants from Denmark, Sweden, Austria, Norway, the United States, Belgium, Poland and Slovenia have formed a partnership “to provide a sustainable and environmentally friendly road infrastructure by developing an integrated methodology for improved control of road transport CO2 emissions. The methodology will be implemented in road asset management systems to optimize the reduction of the part of vehicle CO2 emissions related to road pavement conditions.” It’s in the asphalt industry’s best interest to monitor the information—or misinformation—fed to the researchers participating in MIRIAM as FHWA will be placing importance on the group’s findings. With MIRIAM’s results, it will enable FHWA to select the most appropriate pavement surfaces considering agency costs, public safety, vehicle operating costs and user delay costs. For FHWA, the bottom line is to more effectively manage pavement assets. For the end user, the bottom line is to stay safe while maintaining reasonable vehicle operation costs. While members of the asphalt industry can see clearly how asphalt pavements can save agency costs, increase public safety, reduce vehicle operating costs, and decrease user delay costs during construction, use and maintenance/preservation activities, such claims must be proved through scientific principles. By partnering with European counterparts, U.S. engineers should have positive learning experiences and the opportunity to contribute and derive value from a research foundation. Contact NAPA’s Dr. Howard Marks for more information on the “Concrete Sustainability Hub’s Fuel Economy Model Not Valid for Estimating the Impacts of Pavement Characteristics on Vehicle Fuel Consumption.”
www.theasphaltpro.com | ASPHALT PRO 59
Take Eye Safety Seriously “
The Honeywell Eyelation program is idea for companies of every size,” Dan Birch said. He’s the senior product manager for Rx Products, Honeywell Safety Products. “Safety and HR managers enjoy the benefits of an automated system and the confidence that their workers are wearing the approved safety eyewear for the application, with their current prescription, for the greatest protection.” To begin using the program, end users log on, and then apply a “fitting pad,” which is a one-time use adhesive strip, to the forehead. A built-in camera photographs the employee and proprietary software does the rest. Once the employee selects the frame that’s suitable for his or her work environment, ABOVE TOP: The Honeywell the employee scans his or Eyelation program uses onsite, web-enabled, touch screen kiher prescription and purchasosks to let end users order prees the frames. The program scription safety eyewear without fulfills the order and the emthe human resources professionployee receives the new eyeal’s involvement. ABOVE BOTwear at work in approximateTOM: The dielectric style of ly one to two weeks. the Uvex Pheos safety eyewear comes with Uvex Dura-streme® The Honeywell Eyelation dual action anti-fog, anti-scratch program is available now coating. through major safety equipment distributors in the United States or by contacting the Honeywell Safety Products customer care department directly. The next product Honeywell unveiled is the Uvex Pheos safety eyewear, which combines streamlined styling with technologically advanced materials to deliver high-performance protection. The eyewear’s frameless design features duo-spherical lenses. The dielectric style comes with Uvex Dura-streme® dual action anti-fog, anti-scratch coating. They’re available in two sizes and three lens tints—clear, gray and amber. Like all Uvex® styles, Uvex Pheos offers 100 percent ultraviolent protection and meets the ANSI Z87.1-2010 standard for impact protection. Uvex Pheos eyewear is available now through major safety equipment distributors throughout the Americas. 60 december 2012
For more information on the Honeywell Eyelation program, contact the Safety Products customer care department directly at (800) 446-1802 or visit www.HoneywellSafety.com/Eyelation. For more information on the Uvex Pheos eyewear, contact Honeywell Safety Products customer care department at (800) 430-5490 or visit www.uvex.us. Tell them you saw it in AsphaltPro Magazine.
Powerscreen Displays Warriors
During an open day event for their North American distributors Oct. 16 through 17 in Boston, Powerscreen showcased a full range of crushers and screens featuring the latest design innovations. Delegates from Scania also attended to have feed- ABOVE TOP: Here the XH500 imback sessions and dis- pact crusher feeds recycle to the Warcussions about the Tier rior 1400X screen during the U.S. Open Day in Boston. ABOVE BOT4i/Stage IIIB engines. TOM: Here the XA400S pre-screen The event included vis- jaw crusher feeds blasted granite to its to two neighboring the 1300 Maxtrak cone crusher, which quarry sites to see new feeds a Chieftain 2100S. and existing Powerscreen equipment working together. The first site in Walpole featured an XH500 impact crusher feeding the new Warrior 1400X screening machine working on a recycled concrete and asphalt application. The Warrior 1400X was set at 3 inches (75 mm) while the bottom deck was set at 1 inch (25 mm) producing 3-inch+ (75-mm+), 1 to 3-inch (25 to 75-mm) and 0 to 1-inch (0 to 25-mm). The Powerscreen XH500 is the flagship horizontal impact crusher for the company. It features up to 500 U.S. tons per hour for quarrying, recycling and demolition applications. It features a live independent pre-screen, standard full underbelt product conveyor and optional vibrating underpan. The second site at Wrentham had a new XA400S prescreen jaw crusher feeding a 1300 Maxtrak cone crusher, which in turn fed a Chieftain 2100S screen and a separate Warrior 2400 screen, working on blasted granite. The prescreen on the jaw was set at 2 inches (50-mm) with the Chieftain configured at 1 inch (25 mm) on the top deck, ½ inch (13 mm) on the middle deck and ¼ inch (6 mm) on the bottom deck. The Warrior had a top deck of 4 inches (100 mm) and a middle deck of 2 inches (50 mm).
The Powerscreen X4000S Jaw Crusher incorporates a fully independent high amplitude, hydraulically driven pre-screen with increased drop angle on the bottom deck to improve throughput and overall capacity. Also, the discharge opening from under the chute has been increased from 200 mm to 320 mm for faster prescreened material flow. For more information, contact Powerscreen at +44 28 87 718 500 or firstname.lastname@example.org. Tell them you saw it in AsphaltPro Magazine.
Volvo Rolls On
The new Volvo SD75 soil compactor meets Tier 4i engine requirements while lowering its cost of operation, according to the manufacturer. The SD75 features high centrifugal forces, high frequency and drum weight to produce the energy necessary for compaction and high machine productivity. Dynamic drum forces are adaptable to a wide range of terrain or depth of material. The operator can select high or low amplitudes from the operator control panel. Additionally, two drum frequencies can be chosen with a console switch to compensate for changing soil types and conditions. An optional 5-frequency feature further boosts the machineâ€™s versatility. A center joint provides +/-38 degrees of articulation and +/-17 degrees of drum oscillation for stable, flexible machine performance and operator comfort over rough terrain. The machine is designed to be able to negotiate slopes of up to 33 percent. One highlight of the new SD75 is its powerful 4-cylinder Volvo engine (99.2 horsepower), which combines Tier 4i and EPA certification with fuel efficiency. A hydraulically operated engine cooling fan runs only when needed. Volvo long life coolants protect the machine for up to 6,000 hours. For more information, contact Bill Law at Volvo Construction Equipment at (828) 974-2530 or email@example.com. Tell them you saw it in AsphaltPro Magazine.
Volvoâ€™s SD75 www.theasphaltpro.com | ASPHALT PRO 61
equipment gallery ARTBA Takes Safety in Hand
One of the transportation industry’s most heavily used publications—the Manual on Uniform Traffic Control Devices (MUTCD)—is available for the first time on Apple mobile devices through the American Road & Transportation Builders Association (ARTBA). The MUTCD of course defines the standards by which public and private transportation professionals install and maintain traffic control devices on all public streets, highways and bikeways, providing guidance on the types of shapes, colors and fonts, and installation methods that should be used in road markings and signs, as well as standards by which all U.S. traffic control devices must conform. The e-book format now allows road managers nationwide to access safety information via their smart phones or tablets at the job site or in the office. It’s available for $29.99 through the www.artbastore.org and is formatted for users to search, find, copy, paste, print and save both text and graphics by navigating hyperlinks and setting bookmarks for information about traffic control rules and regulations. Whether you have an iPhone, iPad, iPod or Kindle, you should be able to view the Apple iBookstore and any mobile device can download the MUTCD through Amazon’s bookstore. For more information, visit ARTBA at www.artba.org.
62 december 2012
International Smoothness T
he excellent crew at Fulton Hogan in South Australia placed 460,000 tonnes of deep lift asphalt along 23 kilometers in 18 months to complete the Northern Expressway project. The wearing course is a stone mastic asphalt (SMA). Here you see the haul truck feeding a new SB1500, which wasn’t required on the job, but was 64 december 2012
a piece of equipment the Fulton Hogan crew wanted to assist with mat smoothness. In the end, all 92 lane kilometers featured an average IRI of 0.56. Ken Little of Fulton Hogan attributed the excellent IRI number to a variety of best production and paving practices. “The IRI number is a product of the process,” he said. “We had a real focus
By AsphaltPro Staff
on reducing variation as any action; be it stop/start, change level, end of a run, even stopping the roller introduces variation and diminishes the ride. The aim was to get going and change nothing; long uninterrupted runs have contributed to the good IRI numbers.” Photo courtesy of Fulton Hogan, Adelaide, Australia
here's how it works
D&H Equipment’s Auto Loader M
oving horizontal tanks and plant components means adding into a project’s bid the crane and other lifting equipment rental cost or value depreciation. To help producers get around the expense of large lifting equipment at the plant site, the engineers at D&H Equipment, Ltd., Blanco, Texas, designed the Autoloader to make the company’s containerized equipment more portable. Here’s how it works. The Autoloader is built into the certified container frame that surrounds the equipment, such as a blending unit or tank. Normal operation occurs with the equipment sitting at ground level. When it’s time to move, an operator attaches the portable, 10-horsepower 66 december 2012
hydraulic motor drive box to the back end of the cage with an adapter that requires only one connection. The hydraulic motor then begins to raise the container using 22,000 pounds per square inch to lift up to 75,000 total pounds on four hydraulic cylinders to a maximum lifting height of 66 inches. When the load has reached the desired height, a truck driver backs a trailer into place so that the load is centered above the trailer deck. Ground personnel can tell the driver when he’s perfectly in place. Then the operator at the back of the load flips a switch on the motor drive box to hydraulically lower the container until the load is gently stabilized on the trailer deck.
The legs will continue to contract until they clear the bottom of the container frame. With the load resting on the trailer, ground personnel slide each of the four 72-inch cylinders into the cage frame for transport. The operator disconnects the portable hydraulic motor and stows it for transport as well. At this point, the tank or other containerized load is ready to move to its new plant location where the process will be reversed for unloading. For more information about the D&H Equipment Autoloader, contact D&H Equipment at (830) 833-5366 or firstname.lastname@example.org, or visit www. dhequip.com.
www.theasphaltpro.com | ASPHALT PRO 67
here's how it works
PHCo’s Hot Oil Heat Transfer Unit W
hether it’s mid-December or mid-June, you want automatically controlled, even temperature transfer fluid flowing amid your industrial equipment such as asphalt tanks, silos, jacketed lines, pugmills, weigh buckets, jacketed pumps and other hot mix asphalt (HMA) components. Process Heating Company, Inc., Seattle, has designed a complete system called the Hot Oil Heat Transfer system that uses Lo-Density®, patented Coil-Lock design heating elements to heat, hold and distribute your transfer fluid. Here’s how it works. The hot oil heat transfer unit arrives pre-wired, pre-plumbed and ready for you to mount in any central location at the plant, but PHCo’s Rick Jay suggests locating it closest to whatever its No. 1 68 december 2012
heating priority will be. “If heating the tanks will be the major function, place it near the tanks; near the plant if that’s No. 1 or the silos if they’re the biggest user.” It depends on your use. To use the system, the plant operator presets a timer on the unit’s control panel for early morning startups as needed. Or the operator flips a switch to signal the unit to elevate fluid temperatures. Jay explained that PHCo uses the same open-coil elements in all their heating systems. Depending on the size of system a plant owner needs, from 10 to 250 kilowatts, the all-electric hot oil heat transfer unit could have anywhere from four to 20+ elements. The elements feature low watt density coils to keep the sheath temperature
decreased while reducing damage to the transfer fluid. While the thermostat keeps the fluid is at its optimum temperature, the pump atop the heater vessel circulates the heated transfer oil to the selected plant components, such as the drag slat system, liquid asphalt pumps and so on. In the event the heating system takes the temperature too high, the control panel’s high temperature alarm lights up and shuts the heat off. If the transfer oil in the expansion tank reaches a level below a set mark, the control panel shuts down the system for safety. For more information about PHCo’s lo-density hot oil heat transfer system, contact Rick Jay at (206) 682-3414 or visit www.processheating.com.
“Hot Mix Asphalt, Paving the Highway to the Future”
C.M. Consulting Looking for a used 150 tph hot plant?
WE CAN HELP!
2007 TEREX Counter-Flow Drum Plant, w/diesel fuel burner, 50-ton selferecting, back weighing silo w/batcher & 200 tph slat conveyor. 4-bin cold feed w/scale conveyor & slinger conveyor, computer controlled AC oil pump injection system, baghouse with exhaust fan, dust return blower and rotary air compressor. Portable 20,000 gallon AC tank. Plant moves in 4 loads. This plant has made less than 20,000 tons since new. Plant is FOB Seattle Washington and is available now. CMC is available for set-up & operational training. $850,000 obo
Many New and Used Asphalt Plants for Sale New Portable Counterflow Drum Plants, 100 to 500 TPH .......................................... Call. 2005 ADM 160 TPH Skidded Drum Plant, 2-AC Tanks, 3-bin, 90t Silo ..................... .Call. 1980s Boeing MS-200 250 TPH Portable Drum with Slinger & Burner .................... Call. 90-Ton Silo 350 TPH Drag & 12-Ton Weigh Batcher, very nice! .............................. Call. 1978 Wylie 40 tph Hot Plant. Baghouse. Generator, AC tank Complete & Running ... Call. 1966 MADSEN 5,000-Lb. Batch Plant, Baghouse w/silo and drag ...................... $80,000.
Cliff Mansfield Inc. • P.O. Box 407 • Odell, OR 97044 Office 541-352-7942 • Fax 541-352-7943 • www.hotplantconsulting.com
72 december 2012
resource directory ACE Group........................139, 40 Contact: Carl McKenzie Tel: 888-878-0898 sales.enquiries@ asphaltacesales.com www.asphaltace.com
CEI............................................... 4 Contact: Andy Guth Tel: 800-545-4034 email@example.com www.ceienterprises.com
Heatec, Inc...... Inside Front Cover Contact: Sharlene Burney Tel: 800-235-5200 firstname.lastname@example.org www.heatec.com
Reliable Asphalt Products......................Back Cover Contact: Charles Grote Tel: 502-647-1782 email@example.com www.reliableasphalt.com
Stansteel.............................. 69, 72 Contact: Dawn Kochert Tel: 800-826-0223 firstname.lastname@example.org www.hotmixparts.com
Almix......................................... 11 Tel: 260-672-3004 email@example.com www.almix.com
C.M. Consulting........................ 72 Contact: Cliff Mansfield Tel: 541-354-6188 Cmconsulting@aol.com www.hotplantconsulting.com
Hercules..................................... 62 Tel: 800-777-5617 or 727-796-1300 www.herculesus.com
Roadtec.................................. .7, 9 Contact: Sales Tel: 423-265-0600 Sales@roadtec.com www.roadtec.com
Systems Equipment.................. 35 Contact: Dave Enyart, Sr. Tel: 563-568-6387 Dlenyart@systemsequipment.com www.systemsequipment.com
Rocky Mountain Conference & Expo................... 71 Contact: Heather Clark Tel: 303-518-0618 www.rmaces.org
Tarmac International, Inc........... 67 Contact: Ron Heap Tel 816-220-0700 firstname.lastname@example.org www.tarmacinc.com
Asphalt Drum Mixers.....19-20, 43 Contact: Steve Shawd or Jeff Dunne Tel: 260-637-5729 email@example.com www.admasphaltplants.com Asphalt Plant Products.............. 73 Contact: Tom Holley Tel: 866-595-3268 Cel: 706-466-3678 www.asphaltplantproducts.com Astec, Inc........ 6-37, 41, 57-58, 61 Contact: Tom Baugh Tel: 423-867-4210 firstname.lastname@example.org www.astecinc.com B & S Light Industries...........54-55 Contact: Mike Young Tel: 918-342-1181 Sales@bslight.com www.bslight.com
Dillman Equipmen................28-29 Tel: 608-326-4820 www.dillmanequipment.com Dynapac US............................... 13 Tel: 800-732-6762 E.D. Etnyre................................ 44 Contact: email@example.com Tel: 800-995-2116 www.etnyre.com EZ Street............................. 16, 18 Tel: 800-734-1476 Info@ezstreet-miami.com www.ezstreetasphalt.com Fast-Measure................................72 Tel: 888-876-6050 www.Fast-measure.com
Libra Systems............................ 52 Contact: Ken Cardy Tel: 225-256-1700 Sales@librasystems.com www.librasystems.com Maxam Equipment.................... 47 Contact: Lonnie Greene Tel: 800-292-6070 firstname.lastname@example.org www.maxamequipment.com
Rotochopper, Inc..................... Inside Back Cover Tel: 320-548-3586 Info@rotochopper.com www.rotochopper.com
Top Quality Paving.................... 72 Contact: John Ball Tel 603-624-8300 Tqpaving@yahoo.com www.tqpaving
NAPA......................................... 63 Annual Meeting www.asphaltpavement.org
Rushing Enterprises.................. 62 Contact: Darrell Martin Tel: 800-654-8030 Dmartin@rushingenterprises.com www.rushingenterprises.com
World of Asphalt……............... .70 www.worldofasphalt.com www.asphaltpavement.com
Process Heating........................ 53 Contact: Rick or Ron Jay Tel: 866-682-1582 Ron@processheating.com Rick@processheating.com www.processheating.com
Stansteel AsphaltPlant Products…........... 25 Contact: Dave Payne Tel: 800-826-0223 email@example.com www.stansteel.com
WRT Equipment….................... 62 Contact: Dean Taylor Tel: 800-667-2025 or 306-244-0423 firstname.lastname@example.org www.wrtequipment.com
AsphaltPro’s Resource Directory is designed for you to have quick access to the manufacturers that can get you the information you need to run your business efficiently. Please support the advertisers that support this magazine and tell them you saw them in AsphaltPro magazine.
www.theasphaltpro.com | ASPHALT PRO 73
the last cut
Petroleum Around the Globe By AsphaltPro Staff
As reported recently, China’s been trading its oil in Yuan instead of U.S. dollars since Sept. 6. Iran began accepting payment from China in Yuan back in May, but had already been accepting rupees and mercantile from India and China. While China doesn’t produce oil naturally, the country can impact the global oil landscape through a trade agreement with the Russian Federation, which was signed Sept. 7. According to SOTT. net, the agreement allows the Federation “to sell oil to China in any and all amounts they [China] desire.” At press time, Japan had exported most of its bitumen during the month of September to China. (Japan imported most of its bitumen from Korea that month with its imports of bitumen firming up by 31 percent as compared to August’s imports.) Xiamen Huate Group Corporation Ltd. and Beijing Zhongwu Zhenhua Trading Co. Ltd. is the importer bringing the most bitumen into China during the month of September and a player to watch there. Sources: Various
China took in 81,325 megatonnes of bitumen from Singapore back in August; Indonesia also saw an increase in imports from Singapore to the tune of 37 percent more than what the country took in during the previous month. Source: Petrosil’s Bitumart
AsphaltPro staff has seen a trend whereby Thailand is decreasing its import and export of bitumen. The country’s exports decreased by 11 percent overall during the first half of this year as compared to January through July of 2011. The downward trend has continued with the country’s bitumen exports plummeting by 45 percent in September as compared to August’s exports. What bitumen it still sends out goes to different countries such as Australia, China and Vietnam. As for bringing material in, Thailand’s bitumen imports, most of which come from Malaysia and China, decreased by 23 percent in August when compared to July. Source: Petrosil’s Bitumart
At press time, two refineries in the New York Harbor area were still out of operation after the devastation of Hurricane Sandy. The two refineries typically have a combined capacity of about 300,000 barrels per day (bbl/d), according to the Energy Information Administration (EIA). Even with that capacity offline, things were starting to return to normal in other impacted areas. “Some of the most severe damage from the storm occurred in the New York and New Jersey areas, including the product trading hub in New York Harbor,” EIA reported. 74 december 2012
Liquid Asphalt Cement Prices—average per ton Company, State
Aug ’12 Sept. ’12
NuStar Energy, Ga.
NuStar Energy, N.C.
NuStar Energy, Va.
Assoc’d Asphalt Inman, N.C.
Assoc’d Asphalt Inman, S.C.
Assoc’d Asphalt Inman, Va.
Marathon Petroleum, Tenn.
Marathon Petroleum, N.C.
Valero Petroleum, N.C.
Data for Southeast region, Source: ncdot.org; Data for Massachusetts, Source: mass.gov; Data for California, Source: dot.ca.gov; Data for Missouri, Source: modot.mo.gov; Data for Colorado, Source: CDOT and Cenovus
Crude Oil Activity (U.S. Crude) futures spot data
369.9 m bbl
366.2 m bbl
360.7 m bbl
364.5 m bbl
357.1 m bbl
359.1 m bbl
Sep 21 Sep 28
Diesel Fuel Retail Price (dollars per gallon) Aug 6
367.6 m bbl
365.2 m bbl
364.7 m bbl
Sources: Energy Information Administration
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