Our team developed Plans, Specifications and Estimates (PS&E) for the widening of Interstate 45 in Navarro County, Texas, for the Texas Department of Transportation (TxDOT). The entire PS&E package, which included 30 bridges, was developed in 4½ months to meet the letting schedule.
The project started north of Corsicana and extended south for 22 miles. The existing four-lane divided highway was widened on the inside to create a six-lane undivided section within the existing right-of-way. By strategically dividing the project into two independent, concurrent work packages and streamlining coordination with Union Pacific Railroad and BNSF Railway and franchise utilities, our team was able to efficiently progress the final design packages using a resource-loaded critical path method schedule. Our approach not only allowed TxDOT to save time and meet its accelerated letting schedule, it also enabled the agency to secure critical funding for the coming fiscal year.
The project included full reconstruction and reconfiguration of three Y-interchanges, improving safety by eliminating left-side entrance ramps. In total, we designed 26 main lane bridge widenings and four bridge replacements, including two direct connectors as well as cast-in-place concrete pan girder and precast, pre-stressed concrete beam bridges.
We developed design criteria and layouts for all 30 bridges and advanced final design and plans, specifications, and estimates for each bridge. We also worked closely with the project's geotechnical engineer to evaluate wall types and design six mechanically stabilized earth (MSE) retaining walls and two soil nail walls along the 22-mile corridor.
