Overview
The original Sargent Beach Bridge carrying roadway traffic from the mainland to the island was a barge swing bridge, which was first built in the 1940s and replaced in 1974. The structure had a limited horizonal clearance of approximately 140 feet and was struck by barges about once a month, making it the second-ranked impediment to navigation on the Texas portion of the Gulf Intracoastal Waterway (GIWW). TxDOT decided to replace with a concrete corkscrew high-level bridge that would span the GIWW and provide uninterrupted access. M&M was hired by the precast plant (Bexar Concrete) to perform a value engineering redesign of the superstructure and substructure of the new concrete corkscrew bridge. The three main spans (195’, 300’, 195’) consist of prestressed, spliced, post-tensioned concrete I girders. The remaining 39 spans are made up of prestressed slab beams. All pier caps were redesigned as precast. M&M also performed construction engineering, including erection plans, falsework, formwork, and temporary bracing designs. Work on the project began in 2018 and was successfully completed in 2021.
TxDOT’s allowance for alternate design, coupled with the ingenuity of an engineer, precaster, and contractor, helped the project team successfully navigate site constraints and transportation challenges. The result was savings of materials, costs, and time. The project received the 2021 Best Projects Award of Merit in the Highway/Bridge category, from Engineering News-Record (ENR) Texas-Louisiana Region.
Bridge Geometry
Length of Main Span | 300 Feet |
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Total Project Length | 2,365 Feet |
Lanes on Structure | Two Lanes |