About the Bridge

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F.J. Torras Causeway is a four-lane paved road with a series of Bridges, It travels approximately 4.2 miles over a salt marsh and a series of five tidal rivers (west to east): a branch of Terry Creek/Dupree Creek, the Back River, the Little River, the Mackay River Bridges (part of the Intracoastal Waterway), and the Frederica River. It terminates on Gascoigne Bluff on the western edge of St. Simons Island. Prior to the construction of the Torras Causeway, the only way to reach St. Simons Island was by a ferry that left from a dock in Brunswick and arrived at a pier on the southern tip of the island. The causeway was reconstructed in 1949-50. In the mid-1980s, the causeway was widened from two to four lanes to accommodate the increase in traffic. The four bridges had to be rebuilt and reconstructed to carry four lanes of traffic in each direction.

 

 

Objective

 

Since construction of the bridge hair line and more visible cracks in support beams associated with the Mackay Bridge portion of the causeway had been reported during GDOT inspections. To better predict the remaining life expectancy of the bridge Cleveland Electric Labs (CEL) and ChM4 installed an all optical SHM System monitoring 24/7 with continuous live data with an automatic reporting system. CEL and ChM4 installed a series of XY crack sensors, strain and tilt optical sensors to evaluate whether the cracks are continuing to grow or has reached a stabilized growth pattern that will allow many more years of use. The bridge data evaluated was done by AECOM the Prime for the project.