This project was the last and largest section of the Palmetto Expressway Improvement Program (Entire program was 12 Sections). The primary objective of the project was to increase capacity along the Palmetto Expressway (SR 826) and the Dolphin Expressway (SR 836) while enhancing existing ramp connections and creating connections that did not exist before. The project also made provisions for express lanes connections for future projects. Design innovations, coupled with a well-executed construction plan, allowed for an early completion of the project while providing FDOT $276 million in savings over the Department’s construction estimate.
BCC was the Engineer of Record responsible for developing the structural design for the project, which included 47 new bridge structures as well as an extensive amount of permanent and temporary walls, and overhead sign structures. Structural improvements included:
- 4 Segmental Flyover Bridges
- 4 Steel Plate Girder Bridges
- 39 Florida-I Beam (FIB) Bridges
- MSE walls up to 40 feet in height
- Temporary walls
- Anchored bulkhead walls for the realignment of the Northline Canal
- Over 40 overhead sign structures
- Large size diameter culverts (greater than 20 ft diameter)
The segmental bridges provided movements for 4th and 5th level ramps and consisted of 775 variable depth post-tensioned segments for a total of 7,763 linear feet of bridge. Maximum span length is 266 ft and tallest pier is 81 ft. Balanced cantilever construction method utilizing a launching gantry was used simplifying maintenance of traffic, increasing safety, expediting construction and providing significant cost savings to the Department.
The steel bridges consisted of curved flyover bridges including a 220’ single span bridge with a maximum skew of 56 degrees, and continuous two-span bridges with a maximum span length of 213’ and up to 47-degree skews.
The Florida-I Beam (FIB) bridges utilized all different types of Florida-I Beam sizes, and consisted of single-span and multi-span bridges with span lengths varying between 71 feet to 170 feet. Several bridges are complete replacements of the existing bridges and required phased construction.
A casting yard was located within the project limits for concrete casting of all Florida-I beams, prestressed piles, and MSE wall panels providing significant cost savings.
BCC was the Lead Designer for this project, and provided design services for Structures, Highway, Signing & Pavement Markings, ITS, Lighting, Drainage, and Environmental Permitting.