Designing and building the Bourse Garage and theater complex in part of Philadelphia's old city presented contractors with a challenge. Narrow streets, limited site access, a high water table, and making the building fit with the nearby historic buildings were some of the obstacles contractors overcame to win a Grand Prize in the General Building Contractors Association Concrete Awards Program.
Due to constraints related to a high water table, a mat foundation design was used. The mat design was complicated because compound slopes in the mat surface were required to conform with slopes of the theater floor. Because of the theater complex, many of the columns supporting the parking structure had to be terminated at the ground floor level. This required shifting those column loads by transfer beams or girders. Post-tensioned transfer girders were designed to reduce girder depth, thus allowing headroom. Limited access and narrow local streets ruled out using a precast concrete structural frame. Designers chose a post-tensioned cast-in-place frame, using unbonded tensions.