The Southern Wake Expressway is part of the Interstate 540 outer loop in Raleigh, NC on the southern side of the city that connects Holly Springs, NC to Garner, NC. The first planning for the I-540 project originally started in the early 1970s. In 1976, the planning maps in Raleigh contained “Northern Wake Expressway” which was the first portion of the I-540 loop that was constructed. The first construction of the outer loop was started in 1992 and finished in 1997. The newest expansion of the expressway has several bridges being constructed over wetlands and rivers. The supports for these bridges are 30” in diameter with ½” thick steel wall and are 55’-0” long in length. These bridge pipe piles require a double “progressive dip” for most kettles in the county. Another product that was galvanized on this bridge were the bearing plates supporting the large concrete girders.

The decision to galvanize these pipe piles were for the longevity of service life and the depth that they will be driven into the ground. Most of these pipes were driven down 45’-0” into the ground leaving an exposed 10’-0” above ground. The bearing plates were galvanized for sustainability purposes as well. Both of these products were specified for initial cost savings as well as coating durability.

All 64 loads of these pipe piles were staged at the galvanizing facility and scheduled to ship when the cranes were in place for pile driving. This portion of the project lasted around 2 years requiring long term storage at the galvanizing facility. The bridge pile supports were used for 3 main bridges crossing wetlands and rivers.