PLUS VTRC Update Evaluating BMD Conventional and High RAP Surface Mixtures Through Full-Scale Accelerated Pavement Testing 72 Hours ‘Til Departure: Paving Yeager Airport Paving the Pulse of the City The Broad Street Gateway & Corridor Improvement Project A PUBLICATION OF THE VIRGINIA ASPHALT ASSOCIATION //SPRING & SUMMER ISSUE 2024
Spring/Summer 2024 INSIDE THIS ISSUE Visit vaasphalt.org and follow us on Facebook and LinkedIn for up to date industry and association news. COLUMNS 06 CHAIRMAN’S PERSPECTIVE 08 PRESIDENT’S PERSPECTIVE DEPARTMENTS 30 VAA 2024 PARTNERS 31 AFFILIATE MEMBER SPOTLIGHT: CHANEY ENTERPRISES 31 AFFILIATE MEMBER SPOTLIGHT: EQUIPMENTSHARE VTRC UPDATE 10 Applying the pressure to RA and high RAP. PAVING THE PULSE OF THE CITY 14 Lee Hy works around the clock to keep Richmond moving. 72 HOURS ‘TIL DEPARTURE: PAVING YEAGER AIRPORT 18 Coordination and partnering makes for an exceptional project. BACK TO BASICS: JOINT CONSTRUCTION AND COMPACTION 22 It may be legal, but can you do it right. BACK TO BASICS: FRAP 25 One more step to higher results. MID-ATLANTIC ASPHALT EXPO & CONFERENCE 26 Learn, train, and touch what asphalt has to offfer. TEMPERATURES ARE RISING 27 New heat illness standard is in effect. BUILD YOUR FUTURE 28 VAA launches new scholarship to promote the trades. LEAD-ING THE NEXT GENERATION 29 Tapping young talent for future success. VIRGINIA ASPHALT A PUBLICATION OF THE VIRGINIA ASPHALT ASSOCIATION 7814 Carousel Lane, Suite 310 Richmond, VA 23294 Phone: (804) 288-3169 Email: cfahed@vaasphalt.com OFFICERS Chairman David White Vice Chairman Bobby Hedrick Secretary Tim Boone Treasurer David Branscome, Jr. 1st Ex-Officio Chris Blevins 2nd Ex-Officio David Horton Directors Ken Arthur; Sheila Cramer; Ed Dalrymple, Jr.; Harry King; C.R. Langhorne; Buddy League; Ben Miller; Lonnie Minson; Rob Schwear; Blair Williamson STAFF President Trenton M. Clark, PE Vice President David T. Lee, PE Director Mike C. Dudley Administration Caroline R. Fahed Member Relations Specialist Tigre J. Fortune DESIGN & ADVERTISING Advertising Sales: Ronnie Jacko Design & Layout: Jon Cannon For advertising opportunities and deadlines, contact LLM Publications at (503)445-2234 or ronnie@llmpubs.com. ©2024 Virginia Asphalt Association All rights reserved. The contents of this publication may not be reproduced by any means, in whole or in part, without the prior written consent of the publisher. PUBLISHED MAY 2024 ON THE COVER Lee Hy Construction paving project, Broad Street in downtown Richmond Virginia. VAASPHALT.ORG 05
In the heart of Virginia, the bustling highways are the arteries that connect our communities, yet the safety of our workers and the traveling public stands as a paramount concern. It’s a sobering reality that, in our industry, the only barrier between our employees and potential harm is often just a piece of plastic: a traffic cone or barrel. This stark image serves as a constant reminder of the vulnerabilities faced in work zones, where everyday individuals work diligently to improve our infrastructure, all while being a step away from a traveling public that is increasingly distracted. As President of Superior Paving, I’m often asked what keeps me up at night, and my answer is always the same: the safety of our people. The responsibility weighs heavily on my shoulders, knowing that each person under my watch is someone’s son, daughter, mother, or father. The significance of sending every employee home safely cannot be overstated; there should never be an empty seat at the dinner table. Never. Especially due to a preventable incident. Yet, despite our best efforts, the rising number of work zone incidents suggest that our current approach might be treating the symptoms rather than curing the disease. We add more signs, increase fines, and conduct public awareness campaigns—necessary measures, but are they enough? Are we truly addressing the root cause or merely applying a bandage to a persisting wound? The statistics prove that these strategies are not enough. Therefore, we must fundamentally change how we operate work zones by closing roads to traffic and eliminating the risk altogether. That is attacking the cause. It’s a bold proposition that requires significant logistical planning and public cooperation, but isn’t the safety of our workers and the traveling public worth it? The challenge we face is not insurmountable. It calls for innovation, collaboration, and a relentless pursuit of safety. It demands that we look beyond traditional methods and consider how we can fundamentally change the work zone environment to protect those within and around it. This is not just a call to action for the Virginia Asphalt Association, the Department of Transportation, or law enforcement; it’s CHAIRMAN’S PERSPECTIVE Beyond the Cones: A Call to Action for Work Zone Safety David A. White, President, Superior Paving Corp. a plea to every driver, every community member, and every stakeholder in the state of Virginia to help put safety first. We must collectively strive for a future where work zone safety is not just a priority but a non-negotiable standard. A future where the implementation of comprehensive safety measures transcends compliance and becomes a testament to our commitment to human life. This vision for a safer tomorrow begins with each of us today. It starts with acknowledging the gravity of our responsibility and the critical need to address the root causes of work zone dangers. Let’s unite in our efforts to innovate, educate, and advocate for safer work zones, not just for the sake of rule- following but for the preservation of lives. The journey ahead is daunting, but the goal is clear; together, we can transform the landscape of work zone safety, ensuring that every worker returns home safely, and that every journey through our roadways is a secure passage. Let’s make this our collective mission for the sake of every child and parent waiting with anticipation for their loved ones to come home. It’s a sobering reality that, in our industry, the only barrier between our employees and potential harm is often just a piece of plastic: a traffic cone or barrel. This stark image serves as a constant reminder of the vulnerabilities faced in work zones, where everyday individuals work diligently to improve our infrastructure, all while being a step away from a traveling public that is increasingly distracted. 06 SPRING/SUMMER 2024
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Has anyone noticed the asphalt industry workforce is getting older? According to the career site Zippia, 47% of the workers in the asphalt industry are over 40, and only 25% are between 20 and 30 years old. The average age for the entire construction industry is 41. The Virginia Asphalt Association office reflects the industry we represent: 80% of the staff are over 50, and—well, we will not discuss our average age. For nearly a decade, our association and the entire asphalt industry have asked a seemingly simple question: where are the workers? In Matthew 9:37, Jesus tells his disciples, “The harvest is plentiful, but the workers are few.” While not an apples-to-apples analogy, the same applies to construction work across the United States. What is plentiful is funding. Virginia Legislators and Governors have secured and increased funding for transportation since 2013. While the federal gas tax has not moved since 1993, the Bipartisan Infrastructure Law (BIL) added more federal funds, allowing VDOT to cover the inflationary costs while keeping the program pace steady. Although this is not the case in all states, the funding potential is plentiful in Virginia. So, why are the workers few? For one, the housing recession of 2008 had a significant impact on workers. Plumbers, carpenters, and electricians found other work and never returned to their original trade. Most residential and commercial development stopped in its tracks, and in various parts of the state the building of roads and parking lots did as well. Over the last five years, the growth in other employment sectors, such as e-commerce and warehousing, has enticed employees away from construction. At the same time, the birth rate and legal immigration rate have declined in the U.S. This has created challenges for construction and was part of the impetus to establish the Virginia Infrastructure Academy in partnership with the Virginia Community College System. PRESIDENT’S PERSPECTIVE Where Are the Workers? Trenton M. Clark, PE, President, Virginia Asphalt Association This industry has a wonderful story that few know. There are so many career opportunities. Workers make more than a living wage. Their crew becomes their family. Yet, the days of people beating on the contractor’s doors to get a job are gone. Today’s workforce is different from 30 years ago. Salary is essential, as is personal and family time, not to mention the conditions of the work environment. As you’ll read from David White, site safety is paramount. What does the future workforce look like? How will technology play a role? Will it require a blend of properly trained laborers working with highly skilled equipment operators utilizing technology to provide quality asphalt pavements cost-effectively? How do we reach a new workforce, and how long will it take? It sure won’t happen overnight. However, by working with equipment manufacturers, trade schools, community colleges, and companies willing to take the bold steps required to make this transition, the future is closer than we think and brighter than we can imagine. Stay Safe. Today’s workforce is different from 30 years ago. Salary is essential, as is personal and family time, not to mention the conditions of the work environment. As you’ll read from David White, site safety is paramount. 08 SPRING/SUMMER 2024
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EVALUATING BMD CONVENTIONAL AND HIGH RAP SURFACE MIXTURES THROUGH FULL-SCALE ACCELERATED PAVEMENT TESTING The use of reclaimed asphalt pavement (RAP) is greatly influencing asphalt mixture production and development worldwide. While RAP usage has increased in recent years, its growth plateaued in the U.S. with a national average of around 20% in 2014. The economic and associated environmental benefits gained by using RAP in asphalt mixtures have since encouraged U.S. state agencies to introduce special provisions and specifications allowing its use at higher contents in mixtures. The challenges of using high RAP (HRAP) asphalt mixtures can be effectively addressed by incorporating recycling agents (RAs) and/ or softer binders within a performance-based framework such as the Balanced Mix Design (BMD) approach. This approach provides a tool to properly design and produce engineered asphalt mixtures, including those with higher RAP contents. The definition of HRAP mixtures remains specific to each state, and, in Virginia, HRAP mixtures are specifically defined as those containing RAP content exceeding 30%. Accelerated Pavement Testing: Virginia’s BMD Experiment Laboratory performance tests play a crucial role in the BMD process as they ensure the production of high-performing materials. In addition to performance testing and evaluation in the laboratory, accelerated pavement testing (APT) serves as a valuable tool to bridge the important and significant gap between models developed using laboratory material characterization and the actual long-term pavement performance monitoring. This technique involves applying wheel loading (typically surpassing the design load limit) to a pavement system to assess its response within a significantly condensed time frame. This provides insights into long-term pavement performance monitoring and analysis. Virginia is among the few states that have implemented the use of APT facilities for pavement evaluation purposes. In 2020, a collaborative experiment between the Virginia Transportation Research Council (VTRC), the Virginia Department of Transportation (VDOT), and Virginia Tech (VT) was planned and executed at the Virginia APT facility located at the Virginia Tech Transportation Institute (VTTI). A total of six experimental testing lanes were constructed for this study. These lanes featured the use of conventional and higher RAP contents, RAs, softer binder, and a warm mix asphalt (WMA) additive. Evaluated Mixtures The six evaluated mixtures were: • 30_C: a non-BMD mixture serving as a control and including 30% RAP content and PG 64S-22 asphalt binder (with S denoting standard traffic). This mixture was designed following the conventional Superpave mix design methodology through which the optimum binder content (OBC) was selected at 4% air voids. • 30_O: a BMD optimized version of mixture 30_C (with O denoting optimized) featuring the use of 30% RAP content and a PG 64S-22 at a relatively higher OBC when compared to mixture 30_C. • 45_HR: a BMD HRAP mixture containing 45% RAP and a PG 64S-22. The mixture design resulted in a much higher OBC as compared with all other evaluated mixtures. No softer binder or RA were used during the design and production of this mixture. • 45_HR_RA: a BMD HRAP mixture incorporating 45% RAP, a typical PG 64S-22, and an RA. • 45_HR_L: a BMD HRAP mixture featuring the use of 45% RAP and a softer binder, PG 58-28. • 60_HR_L_RA: a BMD HRAP mixture containing 60% RAP, a softer binder (PG 58-28), and an RA. The second through the sixth mixtures were designed following VDOT BMD specifications using Approach D (performance only). Equipment and Instrumentation The central component of the APT experiment was the Dynatest Heavy Vehicle Simulator (HVS) Mark VI shown in Figure 1a. The HVS automatically regulates surface temperature to ensure that the desired temperature is maintained at a depth of two inches from the surface. Jhony Habbouche, Ph.D., PE Stacey Diefenderfer, Ph.D., PE Brian Diefenderfer, Ph.D., PE Virginia Transportation Research Council 10 SPRING/SUMMER 2024
EVALUATING BMD CONVENTIONAL AND HIGH RAP SURFACE MIXTURES continues on page 13 △ Inside the environmental chamber, a dual tire carriage was mounted. A laser profiler, installed on the HVS carriage (Figure 1b) was used to conduct scans of the pavement surface and quantify the rut depth present at the surface. The loading was applied using a dual tire assembly, utilizing 11.00R22.5 tires inflated to a pressure of 105 psi. A data acquisition system (DAS) was also used to capture signals from various instruments. Experimental Lanes and Test Cells Six APT lanes were constructed with one mixture placed in each lane. Each lane had a length of 300 ft and a width of 10 ft. Within each lane, five test cells were labeled A through E. Each test cell had a length of 24 ft and the five test cells were positioned within the center 200 ft of each lane. Test cells A, C, and E were instrumented with strain gauges, pressure cells, moisture sensors, and thermocouples to collect pavement response data. Test cells B and D served as backup test cells to address unforeseen issues or unexpected damage during the experiment. Figure 2 provides a visual representation of the site layout for the APT testing. The pavement structure was consistent across all six constructed lanes. Each lane was built with a research mixture consisting of two 1.5-inch lifts, with a total thickness of three inches. Each research mixture was placed on top of a 12-inch VDOT 21B base layer, followed by an additional 26-inch layer of VDOT 21B as a subgrade layer. Loading Conditions For each rutting test, there were three phases applied to each cell: an initial wheel load of 9,000 pound force (lbf) for the first two weeks, followed by 12,000 lbf for approximately one week, and then finished with 15,000 lbf for approximately one week. This progressive loading protocol was designed to expedite the development of pavement distresses. The internal pavement temperature was maintained at 40°C (104°F). For the cracking test, the loading protocol implemented for each cell included a wheel load of 15,000 lbf until three million equivalent single axle loads (ESALs) was applied. The internal pavement temperature was maintained at 20°C (68°F). Rutting Experiment Measurements Figure 3a shows the rut depth measurements collected within the 12 rutting test cells, with 2 rutting cells (R1 and R2) for each lane. Mixture 45_HR showed the poorest rutting resistance compared to the other five mixtures, as indicated by its rapid accumulation of rut depth. This performance can be attributed to the significantly higher flexibility resulting from the high OBC used in the design and production of mixture 45_HR. The rutting performance of the remaining five mixtures appeared comparable. A ranking among the corresponding test cells R1 and R2 also proved difficult. Further investigation into the effect of environmental aging was conducted to explain the observed differences in performance between test cells R1 and R2. The progression of rut depth for each mixture, normalized with respect to aging and averaged with respect to cell R1 and R2, is shown in Figure 3b. All BMD HRAP mixtures showed higher rut depths compared to the control mixture 30_C. This can be attributed to the inclusion of an increased binder content, along with the use of an RA, and softer binder grade in BMD HRAP mixtures to balance the mixture and enhance the cracking resistance. Figure 1. (a) Dynatest Mark VI Heavy Vehicle Simulator; (b) Laser Profile Mounted on HVS Carriage (a) (b) 0 50 100 150 200 250 300 ft 10ft N 45_HR_L 30_O 60_HR_L_RA 45_HR 45_HR_RA 30_C L6 L5 L4 L3 L2 L1 A B B B B B B C C C C C C D D D D D D E E E E E E A A A A A Rutting Study Cell Cracking Study Cell Figure 2. Site Layout for the Accelerated Pavement Testing Experiment L1 through L6 = lane numbering; N = North; C = control; O = optimized; HR = high reclaimed asphalt pavement (RAP); RA = recycling agent; L = softer virgin binder grade 0 100,000 200,000 300,000 400,000 500,000 600,000 Measured Rut Depth, mm ESALs 20 18 16 14 12 10 8 6 4 2 0 30_C_R1 45_HR_R1 45_HR_L_R1 30_C_R2 45_HR_R2 45_HR_L_R2 30_O_R1 45_HR_RA_R1 60_HR_RA_R1 30_O_R2 45_HR_RA_R2 60_HR_RA_R2 (a) Figure 3. (a) Rutting Depth for 12 Rutting Test Cells; (b) Normalized Average Rut Depth Values / Curves. ESALs = equivalent single axle loads; C = control; O = optimized; HR = high reclaimed asphalt pavement (RAP); RA = recycling agent; L = softer virgin binder; R1 and R2 = rutting cells 00.511.522.533.544.55 Normalized Rut Depth, mm ESALs x105 25 20 15 10 5 0 30_C 30_O 45_HR 45_HR_RA 45_HR_L 60_HR_L_RA (b) VAASPHALT.ORG 11
EVALUATING BMD CONVENTIONAL AND HIGH RAP SURFACE MIXTURES Mixture 30_C (a) Mixture 45_HR_RA (d) Mixture 45_HR_L (e) (f) Mixture 60_HR_L_RA_C1 (g) Mixture 60_HR_L_RA_C2 (b) Mixture 30_O (c) Mixture 45_HR Figure 5. Cracking Cells After Testing with Cracks Marked: (a) 30_C; (b) 30_O; (c) 45_HR; (d) 45_HR_RA; (e) 45_HR_L; (f) 60_HR_L_RA_C1; (g) 60_HR_L_RA_C2. C = control; O = optimized; HR = high reclaimed asphalt pavement (RAP); RA = recycling agent; L = softer virgin binder; C1 and C2 = cracking cell IDs Figure 4. (a) Number of Passes Corresponding to Observation of Initial Surface Cracking per Cracking Test Cell; (b) Total Surface Crack Length Per Cracking Cell. C = control; O = optimized; HR = high reclaimed asphalt pavement (RAP); RA = recycling agent; L = softer virgin binder; C1 and C2 = cracking cell IDs Number of Passes Until Observed Cracking 30_C 30_O 45_HR 45_HR_RA 45_HR_L 60_HR_RA_L_C1 60_HR_RA_L_C2 400,000 350,000 300,000 250,000 200,000 150,000 100,000 50,000 0 (a) Total Crack Length (mm) 30_C 30_O 45_HR 45_HR_RA 45_HR_L 60_HR_RA_L_C1 60_HR_RA_L_C2 60,000 50,000 40,000 30,000 20,000 10,000 0 (b) 12 SPRING/SUMMER 2024
△ continued from page 11 Cracking Experiment Measurements Passes to Initial Cracking Figure 4a shows the number of loading passes at which the first cracks were observed for each of the tested mixtures. Overall, HRAP mixtures (45% RAP) featuring the use of either RA, or a softer binder grade withstood the highest number of passes before developing the first visible surface crack. This was followed by mixtures 45_HR, 60_HR_RA_L (based on average values from cells C1 and C2), 30_C, and finally 30_O. Cracking Quantification Figure 5 shows the cracking cells of the six experimental lanes after full-scale testing at the end of the experiment. The final cracking length, along with its severity determined by its width, was measured for each test section. During the field survey, it was observed that the majority of identified cracks in the testing sections exhibited low severity, with a crack width of 0.1 mm or less. Some cracks were of medium severity, with a crack width of 0.1–0.4 mm, while few exhibited high severity, with a crack width of greater than 0.4 mm (mainly greater than 0.75 mm). Figure 4b shows the total surface crack length for each cracking cell. Overall, HRAP mixtures (45% RAP) that utilized either RA or a softer binder grade exhibited the least amount of cracking when the experiment was concluded. Closing Remarks The OBC of all BMD mixtures was higher than the control mixture, suggesting that the BMD process may result in additional binder being used for some mixtures. The mixtures that included an RA and/or softer binder (45_HR_RA, 45_HR_L, and 60_HR_RA_L) had a lower OBC when compared to the mixture that did not include an RA and/or softer binder (45_HR). The APT rutting experiment found that BMD mixtures (30_O, 45_HR, 45_HR_RA, 45_HR_L and 60_HR_RA_L) showed higher rut depths compared to the control mixture 30_C. Meanwhile, the APT cracking experiment found that BMD mixtures (30_O, 45_HR, 45_HR_RA, and 45_HR_L) exhibited less total cracking compared to the control mixture (30_C). It was concluded that the dense-graded unmodified surface mixtures with high RAP contents exceeding 30%, as set forth by the current VDOT specifications, can be designed using the current VDOT BMD special provision. Furthermore, the effective use of BMD should include the ability to optimize mixtures using a variety of tools including gradation adjustments and the use of RAs and/ or softer binder, instead of solely relying on increasing the asphalt binder content. Finally, ensuring a sustained progress in the implementation of BMD will contribute to the production of longer-lasting, cost- effective, and environmentally sustainable asphalt mixtures. The BMD framework will continue to support innovative practices and technologies with a promising performance outlook. Acknowledgement The authors express their gratitude to Gerardo Flintsch, Bilin Tong, and Ernesto Urbaez Perez of VTTI, as well as Donald (Clyde) Landreth and Travis Higgs of VDOT Salem District for their valuable assistance with this study. The authors thank Boxley Asphalt Paving and Ingevity for their work in producing the mixtures studied herein. EVALUATING BMD CONVENTIONAL AND HIGH RAP SURFACE MIXTURES VAASPHALT.ORG 13
The Broad Street Gateway & Corridor Improvement Project PAVING THE PULSE OF THE CITY Winner of the 2022 Golden Lute Award C.R. Langhorne, Executive Vice President, Lee Hy Construction LLC 14 SPRING/SUMMER 2024
continues on page 16 △ PAVING THE PULSE OF THE CITY One of the first things people notice as they drive down Broad Street in Richmond, Virginia, is the bright red bus lanes used by the Pulse Bus Rapid Transit (Pulse) system. To improve public safety, the bus lanes were “painted” red, requiring the pavement on Broad Street to be resurfaced. the paving portion of the project was completed, a separate company applied the red epoxy surface to designate the Pulse lanes. The paving phase had to be completed to allow the remaining phases to progress and accomplish the city’s overall timeline. PROJECT EXECUTION In March 2022, Lee Hy Construction (formerly Lee Hy Paving) began work on this pivotal corridor project for the City of Richmond, starting on the 3rd Street end, moving west to the city/county line, and returning east to complete the paving. Like the overall project, the paving portion was also broken into five segments. Each directional segment had to be completed before moving ahead, given the complex maintenance of traffic operations and time restrictions. To accomplish this work, an aggressive schedule and work plan approach was adopted. With Broad Street accommodating over 12,000 vehicles per day, the city sought to minimize the amount and length of traffic disruptions due to paving. This project execution included 24-hours-a-day, five-days-a-week operation. Except 6 pm on Friday evening through 6 pm on Sunday evening, Lee Hy was at work milling, patching, and paving. The crews and inspectors did take a short break during the morning and evening rush hours to prevent traffic congestion, but work resumed once the rush hour passed. Initially, the work was planned to progress from the outside travel lanes and parking lanes to the inside median through a sequence of milling and paving, but that approach was changed to maximize efficiency and speed up the project. Instead, Lee Hy proposed a mill at night and pave during the day approach. While complex with the number of drainage structures, manholes, water valves, and other in-pavement fixtures, the milling could progress with fewer complications and be quieter for the residents living along Broad Street. Along with the separation of the milling and paving operations (day to night), Lee Hy paved from inside to outside, allowing for better control of grades and surface drainage. Utility crews adjusted the traffic lights for the periods between milling and paving to keep cars moving. After milling two inches from the existing roadway, the city specified a fiber-reinforced asphalt surface mix to be placed at This, of course, was a complex project. U.S. Route 250 stretches from Sandusky, Ohio, to Richmond, and the busy thoroughfare of Broad Street is where this highway terminates. The road is composed of a variety of paving materials, some of the sections having been constructed in the 19th century. Today, much of Broad Street is composite (asphalt on jointed concrete) or asphalt pavement, depending on where you look. PROJECT SCOPE The Broad Street Gateway and Corridor Improvement Project was commissioned by the City of Richmond’s Department of Public Works (DPW) and funded by a mix of federal, state, and local monies. According to the City of Richmond’s DPW newsletter, this project “literally led the way,” stretching from the City/Henrico County line on the west near Staples Mill Road to 3rd Street near the heart of downtown Richmond. While the overall project was very complex and had multiple phases over 20 months, the paving tied the entire project together by providing a continuous appearance from end to end. Along with the paving, the project included constructing and installing sidewalks, curbs, ADA ramps, traffic islands, tree planting, lighting, and new street furniture. All project phases were wrapped up by the Spring of 2023, with the paving phase being the first “out the gate.” The existing asphalt surface on Broad Street was old and worn out, with multiple patches (primarily utility), ruts, and numerous cracks resulting from the underlying pavement (primarily concrete) and the continual exposure to car, bus, and truck traffic. Many of the existing curbs and gutter pans had been overlaid with asphalt from prior resurfacing. While not all the curb and gutter were replaced on this project, it was vital to maintain the current pavement surface drainage. For the paving phase, the project contract called for milling the existing asphalt surface to a depth of two inches, spot repairs of the underlying pavement, and paving a new fiber-modified asphalt surface mix. Once VAASPHALT.ORG 15
PAVING THE PULSE OF THE CITY two inches thick. The fiber was supplied by Forta to increase the tensile strength of the new mat. As previously noted, an entire reconstruction of the pavement to address the underlying challenges was not within the scope of the project. However, positive outcomes from fiber-reinforced asphalt surface mixes in Virginia and around the country led to its inclusion in this project. The fiber was used in an SM-12.5D mix per Virginia Department of Transportation specifications. The mix had 30% recycled asphalt pavement (RAP) and a PG 64S-22 binder supplied by Associated Asphalt. Zycotherm SP2 was the warm mix additive used to aid in compaction. When all was said and done, Lee Hy laid over 19,300 tons on 27 lane miles of Broad Street. PROJECT CHALLENGES A project in the middle of Virginia’s capital comes with its challenges. In addition to the traffic, the in-pavement structures, the residents and businesses, a 58-day working window, and the fiber-modified surface mix, Broad Street was getting a new traffic configuration to accommodate the Pulse lanes. Unlike many bus routes, in which the bus stops are along the outside or right side of the roadway, most of the Pulse stops are in the median. The Pulse line was constructed for the sole use of transit buses to improve travel time through the city. These lanes require dedicated traffic lights and markings to keep the buses moving. The challenge was the alignment of the longitudinal paving joints with the future pavement lane markings to avoid driver confusion. Through a series of partnering meetings between the City of Richmond and Lee Hy project staff, a solution was reached: re-align the bus and travel lanes to avoid joint and marking conflicts. As one travels Broad Street today, the smooth ride and red bus lanes garner the driver’s attention–not the longitudinal joints. CONCLUSION The scope and schedule of this project were challenging. To keep the overall five-phase project on time, paving needed to be completed within 58 working days (80 calendar days) over the summer of 2022. Separating the milling and paving operations, allowing utility crews to make their adjustments, and paving from inside to outside kept the project progressing. Through the experience and knowledge of Lee Hy’s paving team and the partnership with the City of Richmond, the project was completed in 25 working days—33 less than the contracted timeframe! A major accomplishment for everyone involved and the users of Broad Street. Lee Hy Paving would like to thank the City of Richmond’s Operations Manager Kenny Horak, and his team of Isaac Mason, Dewayne Winston, Rodney Morris, Keith Hewitt, and Jared Netto. Herb Williams led Lee Hy’s team. We’re honored to be a part of this great project completed for our capital city. △ continued from page 15 16 SPRING/SUMMER 2024
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72 HOURS 'TIL DEPARTURE: PAVING YEAGER AIRPORT 2022 MidAtlantic Masterpiece Award Winner John Crane, Executive Director, Asphalt Pavement Association of West Virginia 18 SPRING/SUMMER 2024
72 HOURS ‘TIL DEPARTURE: PAVING YEAGER AIRPORT The Mid-Atlantic Masterpiece Award honors the top paving project completed the previous year across Maryland, Virginia, and West Virginia. A single submission is permitted per state, and the project is rated on the quality of materials, workmanship, and complexity. During the Mid-Atlantic Asphalt Expo and Conference in December, the inaugural 2022 Mid-Atlantic Masterpiece Pavement was awarded to West Virginia Paving, Inc. from Dunbar, West Virginia, for its work repaving the West Virginia International Yeager Airport (CRW). History of the Airport Originally called the Kanawha Airport, CRW opened for commercial service in December of 1947 after three years of construction. In 1985, the airport was renamed after then-Brigadier General Chuck Yeager, a United States Air Force officer, flying ace, and record-setting test pilot. Chuck Yeager was born in 1923 in Lincoln County, West Virginia, and is well known for being the first pilot in history confirmed to have exceeded the speed of sound in level flight in October 1947 in a Bell X-1. Yeager Airport sees an average of 100 flight operations per day: 63% general aviation, 13% air taxi, 15% military, and 9% airline. The airport also hosts the McLaughlin Air National Guard Base, home to eight C-130 Hercules aircraft and the 130th Airlift Wing, an Air Mobility Command unit. Project Overview The CRW runway 5-23 rehabilitation was a high-profile project commissioned by the Central West Virginia Regional Airport Authority. It was completed over three years and concluded in September 2022. West Virginia (WV) Paving managed all paving operations across three contract packages, ultimately installing a complete structural overlay of the 150 by 6,500-foot runway with two and four inches of P-401 asphalt. Additionally, West Virginia Paving milled and filled three inches on the outer edges (60 feet long) and reconstructed isolated deep pavement sections. In 2021, the second phase required a mill and fill of two inches in the center 30-foot keel section and correction of the elevation for roughly 5,100 feet of the runway surface. Finally, the third phase began in 2022, during which WV Paving placed the final structural overlay, grooved the runway, placed permanent pavement markings, regraded soil in the runway safety areas, and replaced edge and guard lighting. Cumulatively, WV Paving milled roughly 305,000 square yards and placed over 63,000 tons of P-401 asphalt. Much of the work was done with time restrictions, often performed at night before the airfield opened for commercial traffic. However, the final mill and fill (150' x 4700' at 2 inches) and overlay (150' x 6250' at 2 inches) were placed during a 72-hour window. continues on page 20 △ VAASPHALT.ORG 19
72 HOURS ‘TIL DEPARTURE: PAVING YEAGER AIRPORT Project Specifications The CRW project followed the Federal Aviation Administration (FAA) P-401 specifications, utilizing Superpave 19-mm mixtures with coarse and fine limestone aggregates and a small fraction of natural sands. The mixtures were designed at 75 gyrations with a PG 64H-22 (PG 70-22). To meet the tight 72-hour time frame for the final paving, WV Paving utilized two local plants located in Dunbar and Poca, roughly 15 and 20 miles, respectively, from the airport. Each plant was dedicated to its own paving crew, which consisted of a materials transfer vehicle followed by a paver setup for 26 feet and three rollers performing compaction. WV Paving employed 85 trucks, 35 of which were dedicated to milling operations and the remainder dispersed between the two asphalt plants to ensure smooth operation during both day and night shifts. In front of the two pavers, WV Paving utilized four milling crews equipped with GPS and laser leveling systems to complete the roughly 123,000 square yards required to complete the two-inch mill and fill section and the other areas and tie-ins. All milling operations were completed in 16 hours. After the milling, WV Paving used an echelon paving operation to place roughly 23,000 tons of asphalt materials in just 54 hours. This helped WV Paving meet the strict time restraints and reduced the number of longitudinal joints that had to be saw-cut, improving the overall joint quality and appearance. After paving was complete, the asphalt was required to cure before being grooved and permanently striped. The final project stage required rigorous quality control checks throughout the production process, notwithstanding the time constraints. This required 13 lots consisting of 59 materials samples, and over 5,000 survey points to verify the elevation of the runway during the milling and paving processes. After completion of the overlay, a final survey confirmed that the entire runway was within the specified half-inch elevation tolerance. While profilograph roughness was not required, quality control data revealed that the runway had exceptional smoothness, with an overall average International Roughness Index reading of 66.5 inches per mile. While Percent within Limits (PWL) can be a challenging specification, WV Paving came to this project well prepared, as the WV Division of Highways utilizes a similar specification on all its National Highway System routes. The FAA required that each lot’s pay factor be determined by taking the lowest computed pay factor (based on either laboratory air voids and in-place density), all while meeting strict government specifications. Pay Factors for each lab air voids, and in-place density (mat and joint) were based on the statistical percentage of material within their given tolerances, which is calculated with the sample mean and standard deviation of the property. Air voids tolerances were between 2–5%, with the in-place mat density lower threshold being 92.8% △ continued from page 19 20 SPRING/SUMMER 2024
theoretical maximum density (TMD), with joint cores being 90.5% TMD. Pay factors entered a deduction adjustment if the PWL of the property fell below 90. Total core counts for the runway were 88 (48 Mat and 40 joint), with none of the cores failing to meet the minimum thresholds, averaging an in-place mat and joint density of 94.2% and 94.9%, respectively. Acknowledgments Completing this impressive project could not have been accomplished without the roughly 250 people across eight companies working tirelessly to ensure the West Virginia International Yeager Airport had an excellent runway that will serve our community for years. 72 HOURS ‘TIL DEPARTURE: PAVING YEAGER AIRPORT VAASPHALT.ORG 21
BACK TO BASICS: Transverse and Longitudinal Joint Construction and Compaction Thomas Travers, Director of Technical Sales, Astec Industries Charlie Butler, Customer Service Specialist, Hills Paving Equipment Division, Hills Machinery Every paving project consists of two joints—the transverse joint and the longitudinal joint. Only two transverse joints should be formed during a typical day’s paving. How well those joints are constructed and compacted will determine if the driver of a vehicle even notices they exist. Likewise, the project will consist of two longitudinal joints or a longitudinal joint with an outside edge. Since these joints run the length of the project and not a paver width (i.e., transverse), how well they are constructed and compacted greatly impacts the performance of the pavement. The following article will discuss best practices in asphalt paving construction and compaction for both transverse and longitudinal joint construction and compaction. Transverse Joint Construction and Compaction Crews are graded on three areas when constructing a transverse joint: flatness, smoothness, and density. Each is important for both the driver’s experience and the long-term quality of the road. Take a transverse joint at a bridge, for instance. If the joint is constructed poorly, then it could create a launch point with an impact that the driver feels every time they cross the bridge, and the pavement or bridge is impacted every time the tires leave and reconnect with the surface. The effect of such a long-term beating is the wearing of the asphalt or bridge, which can lead to premature failure. Everything in the lifecycle is affected by that load, so the flatter, smoother, and denser the surface, the longer the life of the asphalt and whatever is adjacent. Best Practices First and foremost, a 90-degree or vertical face (i.e., butt joint) is essential at the beginning and end, resulting in a square transverse joint. Saw cutting is usually the best way to achieve this, preferably with new, sharp blades. No worn-out or jagged edges on the blades- it will make an ugly joint and wear out your employees. Next, with wood, steel, or other materials, block the screed off the surface at the start of each lift to allow for the compacting effort of the new mat. The rule of thumb is one-quarter inch per one inch of compacted lift thickness. So, to match a compacted two-inch lift, you’d want to start your screed on top of a half-inch block to give you an uncompacted two-and-a-half-inch mat. Aligning the screed with the joint is critical. You don’t want to overhang or try to perfectly align the face of the screed with the transverse joint, which will require you to shovel material back to the joint to fill it. It’s better to stay short of the joint with the screed and remove some material from the existing pavement versus returning material to it by hand. As a rule, the less hand work (shoveling in material or raking off material), the better. Eliminating the chance for launch points or dips that create longterm problems comes down to the screed’s angle of attack coming off the joint. You want to come off right at the plane of the previous mat. The best way to do this is to use automation with a 30-footlong mat reference ski. There will always be handwork around the joint after it’s created. A straight edge of ten feet or so will do the job and is required in VDOT and many other transportation agencies’ specifications. Span it across the previous day’s compacted mat (or existing pavement for a new construction joint), slide out eight feet on the new lift (pre-compaction), and judge if any deviations will lead to a dip or a launch point. If deviations are noted, add or remove material accordingly to achieve a more consistent plane. To come off smoothly, you need a consistent head of material in front of the screed. If there’s too much material, you’ll climb, and if there’s too little, you’ll drop—avoid the bump and dip. Screed temperature is important at the start. If the screed is cooler than the asphalt material, the operator will have a drop because the material is more likely to be slow coming under the screed, which may lead to marks in the mat. If the screed is the same temperature or hotter, it will disperse the material smoothly and come off the joint true. Compaction concepts on transverse joints are fairly simple: if space allows, parallel compaction to the joint with no vibration and minimal overhang on the adjacent mat is preferred. If space does not allow, the joint should be attacked at varying angles from the previous day’s mat, slowly, and with no vibration. Longitudinal Joint Construction and Compaction Like transverse joint construction, best practices can help deliver an excellent ride for the traveling public and a low- to no-maintenance joint that will result in a longer life cycle for the pavement itself. Here are things to keep in mind. Best Practices To ensure a matching lift to an adjacent compacted mat, the matching joint should be one-quarter inch higher for every inch of the lift it matches up against. Like pulling off a transverse joint, if the final compacted lift thickness is two inches, the uncompacted mat at the longitudinal joint should be ½ inch higher. Densities on confined joints are better because the adjacent mat holds the material and creates a stronger joint. On the unconfined or open edge of a longitudinal joint, the initial restriction of an existing lane or shoulder does not exist. To create the confinement, the end gate on the screed should contact the underlying surface so that the asphalt mix gains initial compaction. If the end gate is up, asphalt material will flow under the end gate, creating a ragged joint with very little initial density and numerous 22 SPRING/SUMMER 2024
air voids. This will allow the mix to cool quickly and result in lower overall density results. Once the mat is laid, the first pass of the breakdown roller should be eight to 12 inches away from the mat edge, and then the second pass overhangs the edge of the joint by approximately six inches. For both passes, the drum is in static mode. This overall compaction approach creates a bridge over the compacted first pass and the uncompacted edge, alleviating some of the blowout that would happen if you put the drum on hot material on an unsupported edge. Straight paving is critical, and paving against a 90-degree joint (i.e., vertical longitudinal joint) will always help improve performance. Any outside influence on the paver will create a serpentine effect as it moves along the roadway. This is why we recommend against truck-to-hopper paving, as the movements and banging of that truck can affect the path of the paver. Material transfer vehicles (MTVs) can take those stresses from the paver and allow the paver operator to do their job to a much higher standard. It also allows them to move along at a more consistent pace. Since changing speeds is one of the biggest impacts on density, we must be consistent in every approach. MTVs also allow for material remixing to provide temperature uniformity, which leads to a more effortless flow of material to the end gates and a better final product with higher consistency. Compaction speed and proximity to the screed are among people’s most common errors. The freshly laid asphalt mix cannot be allowed to harden for any significant amount of time before compaction if you want to achieve your desired densities. Do not pave too fast. As safety allows, ensure your roller is as close to the screed as possible. This will reduce mat imperfections and increase density. A common mistake is often made because someone said, “You can’t run on hot material.” This is incorrect, especially if the drum is the same temperature as the material. This is important in all regions and particularly critical in northern climates due to freeze cycles and associated heaving. Final Considerations When following these practices, remember this: every mat and every roadway is different. Always work to the specs and demands of the job. Take localized conditions and requirements into consideration when making your paving plan. It’s also important to know your equipment. The responsiveness of each machine will affect the quality of the work. The best practices detailed here will help you improve the lifecycle and performance of your asphalt, lead to a higher-quality product, and result in easier paving for your crews. Most importantly, they help maximize the investment of our transportation departments and federal highway resources and the critical tax dollars that make the work possible. We recommend learning more about this topic with further resources from the Virginia Asphalt Associations, local equipment providers such as Hills Machinery and its paving division, Hills Paving Equipment Division, and local representatives for manufacturers such as Astec. BACK TO BASICS: JOINT CONSTRUCTION AND COMPACTION VAASPHALT.ORG 23
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BACK TO BASICS: FRAP: Take It From Me! Tim Boone, President, National Asphalt Manufacturing Corp. Fractionated Recycled Asphalt Pavement, or FRAP, has been gaining more attention as the asphalt industry strives to lower its carbon footprint. For many of us, however, FRAP is nothing new. Many companies, such as National Asphalt Manufacturing Corp., have produced new asphalt mixes using FRAP for years. These mixes, examined through the lens of Environmental Product Declarations (EPDs), have a lower global warming potential (GWP) due to higher recycled asphalt contents and less virgin asphalt binder/aggregate. An Example from the Industry National Asphalt is a single-plant asphalt manufacturing company based in Fairfax, Virginia. Until 1984, we operated an outdated batch plant that could no longer keep up with our customers’ demands. Things in our industry were starting to change. Advancements in plant technology were making great strides. Transportation departments nationwide were beginning to mill off the wearing coarse of asphalt instead of just overlaying it. Milling was creating a product that had little use. It was being landfilled or disposed of in other ways but rarely utilized in newer mixes. The industry recognized the potential use and value of milled asphalt material, including stone and liquid asphalt, and after much research and testing asphalt recycling was finally approved by local transportation departments. In 1985, inspired by these advancements, we decided to upgrade our entire facility to a state-of-the-art parallel flow drum plant that could incorporate recycled asphalt. We also installed a recycled asphalt product (RAP) processor to break apart, sort, and screen the broken and milled asphalt. This was all new technology, and it became a game changer for us and the asphalt industry at large. For years, millions of tons of old, wornout asphalt was thrown in landfills or anywhere else contractors could dispose of the material. Instead, we could allow our customers to bring in old asphalt, and we could then process and incorporate a percentage of it into our mix. By adding environmental and economic stewardship to its focus, the industry has helped turn asphalt into the most recycled product in the United States. The Virginia Department of Transportation (VDOT) initially allowed 10–15% RAP in mixes. We operated under this allowance for many years, processing our RAP into two sizes: a “coarse” product sized at 1.5 inches and a “fine” product sized at nine-sixteenths of an inch. As VDOT became more confident in the quality of RAP mixes, they raised the percentage allowances. However, our parallel flow drum was not designed to produce higher percentage RAP mixes, so we upgraded the National Asphalt facility again to an Astec Double Barrel with better mixing capabilities along with lower air emissions to meet the changing industry. With this upgrade, we began producing mix with an average of 25% RAP. Production seemed to run smoothly, but our Quality Control (QC) Director soon approached me with concerns. The consistency of the mix was all over the place. One sample would be coarse with a high asphalt concrete (AC) content; the next would be fine with a low AC content. In other words, we were struggling to keep our material within specification. The quality of our mix was in jeopardy unless we could find the cause. However, the only thing that had changed in our production was the percentage of RAP. Reducing the percentage of RAP was not an option, but the variation we saw in our gradation and liquid AC could not continue. A short time later, I was able to have a conversation with Astec founder Dr. Don Brock while visiting the Astec headquarters in Chattanooga, Tennessee. During our conversation, I mentioned the issues we were experiencing with mix inconsistency using higher RAP. Don asked me if we “fractionated” our RAP. After seeing the puzzled look on my face, he began to tell me how to screen our finished RAP differently. He then challenged me to go back and test our unprocessed RAP pile and find out what it contained. Once we had that information, he suggested we break the material down to a minimum of two sizes, though three or more sizes would be more beneficial. After my visit with Dr. Brock, I returned to our facility and had our team examine our RAP product to find out what was in our pile. What we found was that over 95% of the millings and broken asphalt we were getting from our customers was surface mix, with a top-size material of one-half to nine-sixteenths of an inch stone. So, the 1.5inch material we produced through our RAP processor resulted in clumps of one-half-inch minus material. To address this, we needed space to store two or more finished products. The problem? WE had no additional space, limited as we were to our facility’s 2.5 acres. We decided to replace our existing screening unit with a larger twodeck model and change how we screened the finished products. We eliminated the 1.5-inch material and limited the top size to nine- sixteenths of an inch. The smaller material now had a top size of one-quarter of an inch. Once we began producing material at these sizes, I had my QC Director test the finished products extensively. The nine-sixteenths material was very clean, comparable to a #8 stone, with a minimal amount of fines to it and a liquid AC content averaging 4.5%. The quarter inch material was comparable to a #10 stone, commonly known as stone dust, averaging 7.2% liquid AC. Overall, the products’ consistency meant we could blend them into our mix with little to no variability. From the moment we began producing material with our fractionated RAP, the variability in our gradation and asphalt contents causing QC issues became a thing of the past. Not to mention, the GWP of our surface mixes dropped below 50, with our base mixes even lower! The Benefits of FRAP Investing in fractionating our RAP has been a huge win for National Asphalt and the industry more broadly. Mix quality and consistency are a high priority: National Asphalt wants to produce the highest quality product, something that our customers can count on to be the same today as tomorrow. Now that we control every component of our mix, that is exactly what they get. VDOT specifications now allow 30% RAP in surface and intermediate asphalt mixes and up to 35% RAP in our base mixes. I believe that even higher RAP percentage mixes are coming. When they do, we’ll be ready. VAASPHALT.ORG 25
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