PESC, an H&H company, provided structural engineering design services for the US 183 NB to IH 35 NB direct connector (DCNN): 35 spans with column heights up to 68ft, steel tub girders, prestressed concrete U-beams; and six MSE retaining walls at DCNN (three wrap-around walls protecting embankment at each abutment), and three cast-in-place footing walls to support the new shared-use paths.

PESC worked closely with partner firms and TxDOT to develop aesthetic details for the direct connector bridges. In particular, the appearance of bridge columns and bent caps were designed to resemble the existing bridge structures to remain at the intersection. The design required a careful balance between aesthetic detail, cost-effectiveness, and constructability.

Interchange improvements at IH-35 and US 183 are intended to alleviate traffic congestion and provide better access from one highway to the other. The TxDOT-funded interchange project consists of three new direct connector bridge structures, reconstruction of one existing direct connector bridge entrance, reconstruction of an existing bridge at St. John’s plus two new adjacent turn-around bridges, construction of new MSE and soil nail retaining walls, improved lower roadways, and new shared-use paths along the frontage roads to improve the mobility options and safety for pedestrians and cyclists.