“The first thing we considered were trench boxes; possibly using the equipment that we had in our fleet or we could easily rent,” said Brian Snode, SHELLY & SANDS’ Project Superintendent. “But we realized with the soil conditions and the existing utilities that were in the ground, plus the surrounding buildings; dropping in a box just wasn’t going to work,” he said. “Also with the highway and the apartment on each sided, we realized we couldn’t vibrate in any sheeting or drive-in a lag wall,” Snode continued. “So when we got down to it, really the only thing that would facilitate our need was a dig-and- push shoring system,” he said. Contractor chooses unconventional Slide Rail shoring system “Dig and Push” is a process most commonly associated with installing a Slide Rail System. Slide Rail is installed by sliding steel panels (similar to trench shield sidewalls) into integrat- ed rails on vertical steel posts–an outside slotted rail first, then an open-face rail on the inside–then pushing the panels and posts incrementally down to grade as the pit is dug. SSI calls in help from Columbus equipment rental compa- ny Baker Corp. Snode, however, had little experience with Slide Rail Sys- tems. Needing help, he contacted his friend Jeff Riddle at Baker Corp for some ideas. “We’ve worked with Shelly and Sands many times before, and have a good relationship with the company and with their personnel,” said Riddle, Baker Corp’s Branch Operations Manager. “So after looking at Bri- an’s project parameters, I knew that an Efficiency Production (manufactured) Slide Rail System would work; maybe the only thing that was going to work,” Riddle said. Added Snode, “When Jeff started showing us how Efficien- cy’s Slide Rail System works, and the versatility of the sys- tem to change depending on ground conditions, well it was refreshing to see that they had a different shoring option for us,” he said. Approval from ODOT for shoring system no sure thing However, it wasn’t just the contractor that had to be con- vinced on the effectiveness of the Slide Rail System. Snode and Riddle needed to also convince ODOT that it would work in the difficult site conditions, and meet their safety require- ments. “We went over the entire installation and removal process with ODOT; how Slide Rail actually works and how it 12 NCP Magazine • April ‘18 meets their safety guidelines for underground construction,” said Riddle. Slide Rail is considered a positive shoring system. It main- tains constant pressure against the sides of the excava- tion and requires no over-digging. This prevents possibly undermining or disturbing the surrounding foundations of buildings, roads, or other structures. A positive shoring sys- tem is a critical requirement for approval from most states’ Department of Transportation—including Ohio’s—for any underground construction. SSI begins work on new sewer from bottom to top Sufficiently assured that Slide Rail met all safety require- ments, ODOT gave SSI the green light to begin work on the new gravity-flow sewer. They started from bottom to top; or downstream to upstream; or literally from the bottom of the hill at Short Street to the top of the hill at 2nd Street. Pit 1 reached down 32 feet to uncover and reroute an ex- isting sewer line. Utilizing the same Slide Rail components from the first excavation, Pit 2 was dug and shored for the installation of the four deep pre-cast sump manholes which contain the hydrodynamic separators.