Site-Specific Shoring Secures Culvert Installation

A well-established national contractor was tasked to install high box culverts to improve the flow of stormwater located in the center of an industrial district. The project would require an excavation cut of 60-ft in length, with a width of 28-ft and a depth of 24-ft; that the Competent Person on-site classified the sandy soil as Type-C-60.

The project site presented several challenges as the excavation cut sat on top of a busy avenue and next to active railroad lines. As a result, the contractor would be required to close sections of the adjacent roads until the project was completed. The project would require a protective system that could properly support the excavation at various depths and provide a large free work area for the installation of two 10-ft wide and 8-ft high box culverts while having a minimal impact on the project’s footprint. The shoring system would also need to address the Cooper E80 load ratings as the railroad would remain active during the installation phase. Additionally, the protective system would need to implement an easy installation process while effectively reducing the disassembly process and consequently restoring the flow of traffic at a much faster rate.

The contractor contacted NTS and after reviewing all of the challenges it was determined that the underground would require a site-specific solution. The NTS team of engineers jumped on board and presented a few cost-effective site-specific solutions that would address all of the challenges. The contractor selected a slide rail with rolling struts and a beam and plate system. The design allowed for a complete cohesive integration while supporting the underground at various depths and pressure loads. The incorporation of the slide rail system on the project provided the best open-span area for the linear section of the project. The slide rail system is a modular component, installed via the dig and push method that can be paired with various protective devices. Once the linear section was secured by the slide rail; two beam and plate systems were installed at each end of the linear run as the contactor would require a large free-span work area for the tie-ins. The beam and plate system is a site-specific engineering approach that performs well under poor soil conditions and tight spaces. Additionally, the beam and plate systems are normally used on projects that require underground support for an extended period of time while remaining a cost-effective solution. Once the underground infrastructure has been completed the contractor will commence with the street restoration phase. The contractor was extremely satisfied with the experience and support were given by the NTS team of engineers who developed a cost-efficient site-specific solution that addressed all the site’s challenges.