Cast In Place Pump Station – Sump Separator Secured By Site Specific Slide Rail with a Dual System 80 Tie Back

A Texas contractor was awarded the construction of a cast in place pump station. The project would require an excavation cut of 91-ft in length, with a width of 27-ft, and a depth of 20-ft. The geotech report classified the wet sandy soil as Type C-80. The project site would be located inside a refinery with the excavation cut adjacent to several operational lines, distillation towers, and different types of refinery machinery. The pressure loads originated from the adjacent structures and ground water found in  the area became a challenge.

The contractor would require a modular protective system that could provide an open span work area in a tight environment while providing a height free clearance as the concrete structure would stand 10’ above ground level. Additionally, the protective system would need to have the capability of securing the underground with an open end. The open end would allow the contractor to easily manage the construction of the concrete structure.

Due to the complexity of the project the contractor would require the assistance of an engineering shoring expert. NTS was able to assist the contractor and after carefully reviewing several shoring options the contractor selected a site specific slide rail with a dual system 80 tie back. Site specific engineered systems provide a high degree of customization that allows for certain protective devices to be customized for unique applications.

For the initial phase, it was determined that a slide rail system with rolling struts would be the most optimal solution thanks to its modular capabilities which added additional support and reinforced the center bay of the protective system. The rolling struts would be utilized until the cast in place would reach a pre-determined height to later be switched to a system 80 tie back with custom made H beam caps as the concrete structure would need additional height clearance to be formed. The H beams were welded onto the end caps to support both ends of the slide rail system. The system 80 was composed of two braces placed at ground level on the outer perimeter of the slide rail secured by clamps. After the pump station has been installed and it is fully operational, the structure will filter the water and remove chemicals allowing the refinery to safely reuse the water. The customer was impressed with the modular and customization capabilities that proved to be a cost effective solution.