- Highway Bridge, Seismic Retrofit,

Client: Missouri Department of Transportation

Location: St. Louis, MO

This project consisted of the seismic retrofit of a double-deck bridge and bridge painting at two disconnected sections. The work began with drilled shafts underneath enlarged footings. Differing site conditions and access made the drilled shafts a large obstacle to overcome during construction. The columns were strengthened by one of two ways. These included installing post-tension strands and encasing the column or installing grouted steel jackets around the column. Hinge seat retrofits and restrainers were both installed in the modification of the structure. The existing bridge caps were post-tensioned. Due to the condition of the structure and access issues, some design changes were necessary to ensure proper seismic retrofit construction.