ACPA Concrete Pavement Progress - Winter 2022-23

WWW.ACPA.ORG 19 Winter // 2022–23 RCC (SPECIAL APPLICATION) SCTAC Hercules Way Greenville, South Carolina CONTRACTOR: Andale Construction*/King Asphalt OWNER: Greenville County ENGINEER: COTRANSCO, LLC SILVER Roller Compacted Concrete on I-59 in Birmingham Jefferson County, Alabama CONTRACTOR: A.G. Peltz, LLC* OWNER: Alabama Department of Transportation ENGINEER: Alabama Department of Transportation Hercules Way, part of the landside pavement at Donaldson Field in Greenville, South Carolina, is the site of the first unbonded RCC whitetopping project. Donaldson Field, which is part of the South Carolina Technology and Aviation Center, was built in 1942 as Greenville Army Air Base, then was renamed Donaldson Air Force Base in 1951. The base was decommissioned in 1962 and returned to the City and County. Over the years, the Technology and Aviation Center has become home to a number of companies, including Lockheed Martin. Lockheed Martin currently maintains and refurbishes the legendary Air Force C-130 Hercules cargo aircraft and Navy P-3 Orion patrol aircraft at Donaldson Center and is about to expand to work on the F-16 fighter jet. As part of this expansion, Hercules Way, the road leading to the Lockheed Martin facility, was slated to be improved by Greenville County. Hercules Way is an 8-inch thick concrete taxiway that was converted to a road after the base was decommissioned. The original pavement was constructed between 60 and 80 years ago and covered with roughly two inches of asphalt several decades ago. By 2021, the asphalt pavement was completely oxidized. Initially, engineers for the County planned to rubblize and overlay or remove the existing pavement and completely reconstruct the pavement. However, after looking at the multiple advantages of RCC (construction speed, durability, cost), the County decided RCC would be the best choice. The price of the RCC option was $695,000. Compared to an estimated $1.3 million cost for the rubblizing project; RCC yielded a 46% cost savings. The RCC was finished using finishing admixtures, power trowels and brooming, providing excellent aesthetics and a quiet surface with adequate texture. It was produced at a local ready-mix concrete supplier, proving that special plants are not necessary. As with many concrete interstate roadways, I-59 near Trussville, Alabama, has been in service for over 45 years—significantly longer than its intended design life. When the Alabama Department of Transportation (ALDOT) decided to bid on an 8-mile reconstruction project on I-59 in 2021, the roadway was in significant need of numerous safety and ride improvements. Historically, ALDOT has replaced asphalt shoulders with like pavement. However, with this project, ALDOT had a unique challenge in that the existing shoulders had pavement edge drains installed below the existing shoulder pavement. RCC was selected by ALDOT as the best-value pavement for shoulder reconstruction for multiple reasons. First, the existing edge drains in the pavement are at a 5.5-inch depth, and ALDOT did not want to disturb these costly drainage structures. In addition, during the mainline rehab, ALDOT used the shoulder to carry temporary traffic, requiring a pavement solution with both high strength and the ability to return traffic in a timely manner. With its rapid flexural and compressive strength gain and ability to place a single lift up to 10 inches in one pass, utilizing RCC allowed ALDOT to meet interstate drop-off limitations and keep the adjacent interstate lanes open daily. Finally, as the prime contractor, A.G. Peltz Group was able to bid and complete the entire project at $13.1 million, on the lower end of the bracket estimate range of $12.6 to $15.4 million established by ALDOT. This included over 128,000 square yards of RCC shoulders and ramps, 3,500 cubic yards of interstate mainline rehabilitation and 246,000 square yards of concrete grinding for smoothness. This was the first ALDOT shoulder and ramp project that utilized RCC and the first ALDOT paving project to use portland limestone cement in lieu of traditional cement, reducing typical carbon emissions by 10% minimum. From a contractor standpoint, the project was one of the thinnest (5-inch depth) and narrowest (5 feet in some places) pavements placed by AGP, requiring creative modifications to the RCC placement equipment. The end result for ALDOT was a low-maintenance, long-term shoulder pavement along with a rehabilitated concrete mainline, which will allow the existing concrete interstate to stay in service for another 10-plus years. GOLD