A 2,340′ cast-in-place segmental bridge carrying SR60 from Tampa to Clearwater in Florida. The project was delivered by the contractor and their engineering team in a design/build format. Long spans crossing the water were built in balanced cantilever using form travelers. Severe damage was found in the channel columns during cantilever construction, and contractors stopped the work until an appropriate repair could be implemented. The new Memorial Causeway Bridge is a 2340′ long concrete box girder bridge built using bo th cast-in-place on falsework and segmental balanced cantilever construction. The superstructure is comprised of twin single cell box girders with widths of 54′-3½” and depths varying from 18′-3½” to 9′-3½”. The lengths of the 9 spans of the bridge are: 168′, 173′, 264′, 350′, 360′, 350′, 280′, 209′ and 186′. The substructure of the bridge consists of reinforced concrete piers and footings supported by reinforced concrete drilled shafts.
Corven Engineering Role: Channel columns supporting the 360′ main span and 350′ adjacent spans were heavily cracked during cantilever construction. Corven Engineering was retained to evaluate the condition of the columns and make recommendations with regard to remediation of the bridge. This work included time-dependent construction analyses to determine the forces acting on the columns and non-linear column studies to determine the state of stress within the columns. The work concluded with the recommendation to replace the damaged channel piers from underneath the completed superstructure with new twin-wall columns. This solution was implemented by the design/build team.