Slide Rail System Used for Construction of Bridge Foundations

A South Carolina contractor was tasked to drive H-piles and pour new foundation footings that will support a new bridge on a busy interstate highway. The project would require a linear run of 32-ft with a width of 13-ft and a depth of 12-ft in a clay mixture that the Competent Person classified as Type-C-60 soil.

The project site was located 10-ft from the centerline of an existing railroad and 5-ft from a two-lane road. The project would require a protective system that could secure the underground excavation while providing an open span area for the new foundations. The system would also need to stabilize and maintain the integrity of the adjacent structures. Additionally, the underground protective system would only be able to secure up to 12-ft of depth due to the surge charge load originated by the railroad lines classified with a Cooper Rating of E-80.

The contractor contacted NTS, and after carefully reviewing several protective systems; the contractor selected a slide rail system. The slide rail system is a unique modular protective system, typically installed by the dig and push method. Panels are threaded along the interior grooves of the slide rail post at the top of the excavation and brought to depth ahead of the excavator’s cut. For this project, the slide rail system provided the needed space for the contractor to form and pour the bridge foundations while maintaining and securing the integrity of the railroad lines running parallel to the excavation cut. The contractor was extremely satisfied with the performance and safety provided by the slide rail system during the construction of the new bridge foundations.