The westbound bridge on SR 528 over the Indian River (Bridge No. 700016) is part of the Bennett Causeway and provides a link from the mainland of Brevard County to Merritt Island and Cape Canaveral. The existing westbound bridge was built in 1963 and is now considered to be functionally obsolete. However, the eastbound bridge was constructed in 1970 and is scheduled to remain in service for the next 10 to 15 years. The bridge is located in environmentally sensitive Class II waters, which are designated as a shellfish harvesting area and are the natural habitat of the West Indian Manatee.

The replacement bridge will utilize a vertical alignment with 3% grades on the approaches and provide a minimum vertical clearance of 65’ above mean high water (MHW) at the edge of the channel. The current USCG requirement of providing 125’ of horizontal clearance is achieved by attaching the new fender system directly to the main channel piers. This concept allows for the main channel to be spanned with a simple span superstructure consisting of 8-Modified AASHTO Type VI beams and a 161’ main span. The approach spans utilize a superstructure consisting of 6-Modified AASHTO Type VI beams and 153’ spans.

Deep foundations are required to support the large axial loads and the horizontal ship impact loads for the SR 528 bridge replacement. All of the piers are hammerhead type piers and the viable foundation alternates that were considered are 30" prestressed concrete piles and 60" diameter cylinder piles. Two separate foundation layouts are provided since the large cylinder piles have only recently been used successfully in the state of Florida and there is limited cost data available and concerns about their availability. The foundations are all designed with plumb piles and the 30" prestressed piles make use of a steel pipe embedded at the pile head in order to provide the required fixity and additional lateral capacity for the ship impact loads. The Department also incorporated the use of additional pressure meter soil testing so that site-specific geotechnical information could be utilized in an effort to economize the foundation design.

The total length of the SR 528 bridge replacement is 3,844’ and the overall project limits also include approximately 3,000 feet of roadway and drainage improvements in order to transition the alignment to the new bridge that is parallel to the existing eastbound bridge.