Excessive hydrostatic pressure severely compromised a residential seawall in Myrtle Beach, SC. Inadequate drainage for landward rainwater led to undue stress on the structure’s panels. As a result, water seeped through the joints, carrying soil particles and eroding the supporting earth on the inland side. This case study examines how a Seawall Repair Network® contractor Waterbridge tackled this urgent problem.
Repair Materials
The contractor used SW-RP1, a structural polymer foam, to repair the leaks and erosion. This eco-friendly seawall repair foam is known for its exceptional strength and durability. Furthermore, SW-RP1 is certified to NSF (61-5) standards, making it safe for contact with potable water. In addition to SW-RP1, a hydrostatic pressure control system was installed. This system consists of dewatering channels with panel filters to alleviate pressure from water buildup behind the seawall while keeping supporting soil in place.
Procedures
The repair process began with injecting SW-RP1 behind each seawall panel joint. This step served two purposes: simultaneously sealing the seams and stabilizing the supporting soil. The structural polymer foam quickly expanded, permeating loose soil, filling voids, and creating a robust water barrier. Next, the team installed the hydrostatic pressure control system. This involved coring dewatering channels through the wall and the newly installed SW-RP1 layer and placing pressure control technology in the channels to regulate water flow behind the wall. By taking these steps, the contractors ensured a comprehensive solution to the seawall’s issues, addressing immediate damage and potential future problems.
Results
The project was completed in just two days, showcasing the efficiency of the chosen repair methods. The repairs successfully sealed the wall and stabilized the soil. Most importantly, the property owners were satisfied with the outcome. This case study demonstrates the effectiveness of using SW-RP1 and implementing hydrostatic pressure control systems for seawall repairs.