RAM construction was subcontract by Blythe Construction to perform bridge deck patching, epoxy overlay and various joint repairs on 7 structures that were included on a paving project for The North Carolina Department of Transportation. The project was located on I-77 and I-485 on the south side of Charlotte. Like many major cities, the interstates leading in and out of town experiences extreme congestion. Because of traffic volumes, construction activities were limited to 7 to 9 hours of time each night. Along with the structure work that RAM was performing, there was also concurrent mainline asphalt paving and bridge beam repairs. With multiple operations occurring each night, daily coordination and schedule adjustments were necessary to ensure that the interstate was opened in time for morning rush hour and overall project completion.
RAM was required to plan out how much could be completed within the nightly time frames for each item of work. The epoxy overlay was required to have both lifts installed each night, which was also temperature sensitive. To further complicate the placement of the epoxy overlay, the bridges were located within the areas that were receiving new asphalt paving. RAM utilized specialized surface cleaning techniques so that the epoxy overlay would achieve proper bond strength and perform per the specifications. The project also called for various joints to receive a polymeric header. These locations required 6 inches on each side to be removed and header material placed back to reestablish a proper surface for new joint seals to adhere to. Similar to the epoxy overlay, a fixed amount of time was required for the product to achieve strength to support vehicular traffic. RAM planned out how much time was needed for the removal process, placement of header, and cure time for each work night.
The most unique aspect of the project was the neoprene joint seals that were held in place by metal retention plates on either side of the joint opening. The contract called for the old seal to be removed and a new continuous seal to be installed while maintaining traffic at all times. This required an extreme amount of coordination between RAM, NCDOT, The Prime Contractor, The Traffic Control Subcontractor and the Police Department. Traffic was shifted and the seal was installed from one barrier wall to the middle of the bridge and then traffic was switched and the seal was installed across the remaining portion of the bridge deck. At the completion of the project, the new joint seal was water tested to ensure a 100 percent waterproof sealed joint in order to prohibit rain water and contaminates from leaking on to the bridge pier caps.