April 2011 Vol. 66 No. 4
Features
Complex Shoring Solution
What do you call a job that requires four different pipe jacking pits to install a new 72-inch sanitary sewer pipe? While that may sound like a standard job, the reality was much different.
It required excavations that ranged from 20-feet deep to 32-feet deep, had an active 21-inch sanitary sewer line running through one of the pits, a pond directly next to another of the pits, a creek less than 12-feet away, had a mix of sticky clay soil and running sand, there was an apartment building nearby, and also had a highly traveled road 15-feet away.
But if you are Lowe Construction, you would call it a successful job.
Lowe Construction contacted Pro-Tec Equipment early-on in the process to design a plan to safely and efficiently protect their workers. According to Joshua Thorne, Pro-Tec Equipment’s slide rail manager, “with the mix of bad soil conditions, the proximity to a building and a road, and the overall scope of the project, I was confident that the Pro-Tec Slide Rail System would be able to get the job done for Lowe.”
The Pro-Tec Equipment Slide Rail System is a dig and push-style system. With its modular, flexible design, the system can comply with a wide variety of shapes and sizes. The Pro-Tec Slide Rail Shoring System is installed from the top down and removed from the bottom up, minimizing size of excavations, soil disturbances and restoration time and cost. The installation is done with low vibration, providing soil support for excavations, adjacent structures and existing utilities.
“The original plans called for a beam and lag system,” said Scott Bazinet, president of Lowe Construction. “We asked the engineers if we could use the Pro-Tec Slide Rail System instead of the beam and lag. They were happy to allow it.”
Special requirements
The project, Saddleback Sanitary, located in Grand Rapids, MI, called for a low-vibration system, since all the work would be taking place in close proximity to multiple apartment buildings. “In past projects when we used the slide rail system, we were able to push the post in place with our excavator bucket,” said Scott. “Since we were so close to the apartment buildings, we had to take it a step further and pre-drill the post holes.”
“On all four of the boring and jacking pits, we had limited access,” says Kim Sprague, field superintendent for Lowe Construction. “We had a creek nearby on the first pit, a pond next to the second pit and apartment buildings and a road for the other two pits.” With Pro-Tec’s patented panel installation tool (P.I.T. Boss), having limited access is merely a minor inconvenience. “We used the P.I.T. Boss on three out of the four pits we installed,” said Josh Brown, one of the Pro-Tec Equipment Slide Rail consultants on the Saddleback Sanitary project. “Without the P.I.T. Boss, at the depths that Lowe Construction was working, there would have been no easy way to install those panels to the proper depth.”
The slide rail shoring system is made up of five main components: corner post, spreader post (also known as linear rails), spreader beams, roller beams and panels. The panels used in the slide rail system are similar to trench shields; however, they are designed and reinforced in a way that allows them to stand up to the rigorous environment in which slide rail systems are commonly used.
Worst conditions
On the site, Lowe Construction was using two 100,000- pound excavators. At one point, they even enlisted the services of a 700 Hitachi excavator. “In my 25-plus years of dirt work,” said Sprague, “these were the worst job conditions I’ve come across. We had sticky and firm clay, mixed in with running sand. They weren’t on top of each other. In some cases, they ran vertically or even diagonally.”
For the Saddleback Sanitary Project, Lowe Construction was the primary sub-contractor for the boring and jacking. The general contractor on the site was Jackson-Merkey Contractors, out of Muskegon, MI.
Lowe Construction is based out of Horton, MI. Founded in 1974, their primary focus is in auger boring and jacking, pipe jacking and tunneling.
Pro-Tec Equipment has been a leading producer of trench shoring and shielding equipment since 1995. Based out of Charlotte, MI, Pro-Tec Equipment’s products are P.E. certified to meet and\or exceed OSHA standards.
FOR MORE INFO:
Pro-Tec Equipment, (800) 292-1225, www.pro-tecequipment.com
Lowe Construction, (517) 529-9406, www.lowecon.net
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