VAASPHALT.ORG 15 PAVING AGAINST THE CLOCK CHAMBERS FIELD RUNWAY-NS NORFOLK continues on page 16 △ The Golden LuteAward is given to the top paving project inVirginia completed the previous year and is based on the quality ofmaterials, workmanship and complexity. In addition, subjective and objectivemeasures are used to select the ultimatewinner. During the Mid-Atlantic Asphalt Expo and Conference in December, the 2021 Golden Lutewas awarded to Branscome, Inc. for the Chambers Field at Naval Station Norfolk project. Project Overview The Chambers Field Runway 10-28 repair was a high- profile, fast-tracked project commissioned by the Norfolk Naval Facility, or NAVFAC Mid-Atlantic, completed between March 2021 and July 2021. It required a complete resurfacing of a 200 by 6,500 foot-long runway, with three to six feet of variable depth P401 asphalt. The project also involved upgrading the Instrument Landing System (ILS) or airfield lighting and signage, as well as environmental improvement, reverting approximately 94,000 square yards of paved surfaces to green space. As the primary contractor, Branscome was responsible for the complete site package, including repairing cracks and other deficiencies in the existing concrete and asphalt; demolition and regrading the existing runway by way of Universal Total Station (UTS) milling; placing a surface treatment on the runway subgrade paving; pavement marking of the new runway; support for the ILS with micropile foundations; and new electrical duct banks. The runway consisted of 39,000 tons of asphalt using three different mix designs and 176,000 square yards of milling, which varied in thickness from 3 to 8 inches. The infield area involved an additional 94,000 square yards of milling, which varied in thickness from six to 48 inches. The schedule was the most significant concern going into this project. To support the construction effort, the Navy had to completely shut down the runway, rerouting all mission-essential air traffic operations away from one of the largest naval airports in the country. Due to this level of effort, all construction work had to be done on an accelerated schedule to reopen the runway on time. Four milling crews, two paving crews, and 70 trucks per day were required to meet the demanding schedule, which required all paving work to be completed in 12 days. Special Considerations Chambers Field was one of the first government- commissioned jobs that required personnel to undergo the Airfield Asphalt Certification Program to meet Unified Facilities Guide Specifications (UFGS). Branscome sent personnel to the National Center for Asphalt Technology at Auburn University to earn these certifications and hosted the Navy-led inspection of Branscome’s Hampton Asphalt lab and plant to confirm specific requirements, including accreditation by the American Association of State Highway and Transportation Officials. Each lot’s pay factor was determined by taking the lowest computed pay factor based on either laboratory air voids, in-place density, or grade/smoothness; all while meeting strict government specifications. For example, the lab air voids pay factor was based on the mean absolute deviation of lab voids from the job mix formula. Mat cores were to be within 94–96% theoretical maximum density (TMD), with joint cores above 92.5% TMD. In addition, joints that ran along concrete had to be cored six inches away from the plain cement concrete joint and only rolled by a rubber-tired roller, requiring the same density as regular mat cores. Surface smoothness was also essential for this project, so grades were checked at several stages throughout the paving process to keep them on target. The Branscome-produced asphalt material underwent thorough lab testing, then was verified by profilograph and other performance QC checks after paving was complete. The job included three mix designs: • 30,217.08 tons of P401 (¾ inch nominal maximum) virgin, 75 gyrations, that required PG 76-22 liquid. This design also had a very tight specification on coarse aggregate, requiring specialized stone matrix asphalt from a different quarry (which also added to logistical and planning issues). This mix design was tested over 13 lots, with 60 samples. Some days required as many as six samples to keep up with production. In addition, 126 joint/mat cores were cut and weighed out by a third-party testing firm. The asphalt content of this mix was kept to a 0.12 standard deviation throughout the project. The schedule was the most significant concern going into this project. To support the construction effort, the Navy had to completely shut down the runway, rerouting all mission-essential air traffic operations away from one of the largest naval airports in the country. Due to this level of effort, all construction work had to be done on an accelerated schedule to reopen the runway on time.
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