One of our public agency clients developed a well-planned and executed program to improve the serviceability of their aging highways and bridges. The goal of the program is to improve the condition and load-carrying capacity of state-owned bridges and culverts as well as extend asset service life to a minimum of 25 years. The early years of the program focused on bridge rehabilitation and preservation, and Collins has been awarded three consecutive on-call bridge preservation contracts since 2016 supporting this program.
Collins helped develop a first-of-its-kind bridge maintenance preservation design for ten bridges on the I-95 and I-195 interchange corridors. Our team provided the unique specifications-based design of high-quality bridge maintenance activities that generally included bridge washing, concrete sealing, deck joint replacement, concrete superstructure and deck repairs, scupper and downspout repairs, and bituminous concrete milling and paving. Deliverables included preparing 90% and PS&E specifications, traffic management plans, construction cost estimates, and supplemental permitting documentation.
In 2019, under this contract, a seven-span bridge over the tidally influenced river founded on pile-supported reinforced concrete piers with granite facing was found to have significant scour that exposed the concrete tremie seals at two piers and was undergoing significant erosion, exposing several steel H-piles. Collins developed a short-term underwater repair design and completed contract documents for repair construction for the bridge in accordance with agencies’ design and construction policies, procedures, and standard specifications. Collins also provided underwater quality control inspections for the agency and verified quantities.
Fast river flows during tide changes coupled with low overhead clearances under the superstructure resulted in the completion of a performance-based set of contract documents that enabled flexibility in the mean and methods. Final construction consisted of doweled and staked grout bags placed to fill existing tremie voids and to surround the perimeter of the tremie seals with competent materials.