Sylvan Avenue Bridge Replacement

The previous Trinity River crossing consisted of three separate bridges. Two of them crossed the east and west levees, and one low-water crossing bridge over the Trinity River. With the Trinity River crossing sitting at such a low elevation in the Trinity River floodplain, it became impassable at times of high water, accentuating the need for a new, more hydraulically efficient crossing. The new bridge raises the profile of Sylvan Avenue out of the floodplain. In fact, the crossing is built above the 800-year flood elevation providing uninterrupted traffic flow year round.

The new Sylvan Avenue Bridge is a 23-span bridge that incorporates context sensitive features such as ornamental lighting, open railings, and a ramp which allows both vehicular and pedestrian access to Trammell Crow Park and its soccer fields below. It is composed of precast concrete I-girders and spliced post-tensioned girder for the longer spans over the river crossing. There are 3 post-tensioned units, each consisting of 3 spans. Summit Engineering (Summit) provided construction engineering to the contractor and developed shop drawings for the precaster for the spliced, post-tensioned units. This type of construction was relatively new to TxDOT and the City of Dallas.  Summit introduced a number of innovative concepts to enhance the constructability of the project. To reduce construction costs, Summit developed an integral corbel system to support the girders during construction of the post-tensioned units. This eliminated the need for external strongbacks at 132 total splice locations and enabled all of the bridge girders to be erected in a single phase of construction.