Cantilever Beam & Plate System Secures Oil Water Separator Project

A commercial technology and innovation district was in need of upgrading their existing storm water management program. The upgrade would enable the commercial district to properly treat the waste water that’s discharged into the river streams, a critical task for local authorities. The contractor in charge of the project was tasked with installing an oil water tank separator. Oil tank separators are designed to remove oil, grease and other contaminant particles from water and waste water. The contractor’s initial task required the excavation of a pit that measured 45-ft long, 16-ft wide with a depth of 17-ft in a clay soil that the Competent Person classified the as C-60.

The protective system would need to address a few obstacles related to the excavation site, including the proximity to two existing buildings, an active hanger, and an operational runway. The contractor estimated that the loads exerted from the nearby structures would negatively impact the soil conditions in the area. To avoid the potential of a cave in or structural damage to the nearby structures; the contractor would be required to stabilize the excavation with the use of a shoring system.

The contractor requested specialized engineered assistance for this project to ensure the system would meet the site specific issues present on the project. NTS provided a few site-specific options that the contractor carefully evaluated and ultimately selected a cantilever beam and plate system. A cantilever beam and plate system provides a large open span work areas by utilizing beams that are driven and pushed below grade to provide the strength for the system against the loads of the soil walls. Steel plates are inserted through the beams flanges to close the system and transfer the strength of the beams to the soil walls. The cantilever beam and plate system allowed for a free span excavation that also provided positive soil support to minimize soil disturbance that could have impacted the adjacent structure. Once complete, the project will help to ensure the adequate discharge of filtered waste water in accordance EPA regulations. The contractor was extremely satisfied with the cantilever beam and plate system and its high level of customization.