Location: Key Biscayne, FL
Client: Miami-Dade County Public Works Department
Hardesty & Hanover and Kiewit Infrastructure South teamed together to provide design-build services for the design, demolition and construction of a new superstructure for the Bear Cut and West Bridges, which are part of the Rickenbacker Causeway to Key Biscayne. The project’s goal was to replace the superstructure and widen the existing bridge an additional 15 feet, with a designated bikeway, within a year so that the Annual Professional Tennis Tournament, held on the Island every April, would not be disrupted. The original bridges were built in 1947 and the severe coastal environment had severely deteriorated the steel superstructure. Accelerated corrosion detected in the 2012 Biennial Inspection mandated the emergency replacement of the bridges.
The new superstructure is modified prestressed concrete AASHTO Type II Girders. The girders were modified in height so that the existing bridge profile could be maintained. In addition, the new concrete superstructure had to maintain the original dead load so that the existing substructure would not be overstressed. Additional improvements included lighting, drainage, and approach roadways. The design and construction was completed within 16 months and included an investigation of an unknown foundation.
In 2014, the project was awarded the Best Project – Renovation/Rehabilitation/ Restoration and the Honor Award – Infrastructure by the Design-Build Institute of America (DBIA) Southeast Region. In 2015, the project was named Project of the Year (III) by the Cuban-American Association of Civil Engineers.