Efficiency Slide Rail System Ensures Excavation Safety for Marcus Construction
Shoring System Facilitates Difficult Dig: Marcus Construction Uses Slide Rail System to Safely Excavate a Receiving Pit as Part of the North Prairie Ag Expansion
A slide rail shoring system from Efficiency Production aided in the construction of a rail receiving pit and tunnel project at North Prairie Ag in Nekoma, North Dakota.
“It was a helpful structural system,” says Travis Roedinger, Project Manager for Marcus Construction of Willmar, Minnesota. “We were working in close proximity to the rail tracks, and the depth of the hole was an issue. Strategically, we needed a solid engineered protection plan that would meet the criteria of the rail system.”
Stringent guidelines are in place to ensure safety when working near railroad tracks. Efficiency Production hired an outside engineer for site-specific engineering to verify that the Slide Rail components would meet those requirements and produced drawings for the contractor to follow.
The Slide Rail System uses vertical steel posts and steel panels, such as those used as trench shield sidewalls. The contractor installs the system by sliding the panels into rails on the posts and then pushing additional panels and posts down as the pit is dug.
“You cannot disturb dirt under railroad tracks,” says Tim Hurst, Manager of the Special Ops Shoring Division at Efficiency Production in Mason, Michigan. “The Slide Rail System’s panel and post design prevents trench wall loss, because it is installed gradually. We call that a ‘dig and push’ shoring system. You are not at any time disturbing the dirt around the excavation.”
Marcus Construction dug a 20-foot-deep, 20-foot-wide hole for the rail receiving foundation. The pit was within 10 feet of an operational rail line. Crews ran into hard shale and water, which required constant dewatering pumps. Safety was the highest priority throughout the project. Trains will drive over the receiving pit foundation to unload the rail cars.
“The train cargo goes over the pit and they dump the cargo car by car. It’s a hoppercar,” says James McRay, Director of Marketing and Media for Efficiency Production.
The rail receiving was part of a larger fertilizer storage project, in which Marcus Construction built a 22,000-ton dry storage facility for North Prairie Ag as part of an expansion. North Prairie Ag was founded in 1925 to provide area growers with quality agricultural services.
Sackett-Waconia, an equipment supplier in Waconia, Minnesota, installed a tower system at the site, with four overhead tank sections.
The Shoring System
Efficiency Production developed the component Slide Rail shoring system. It can be rented on a weekly or monthly basis. “It’s about half the cost of sheeting,” McRay says.
The unloading pit took about two days to dig while placing the shoring system. The panels slide into the void.
“You dig ahead of the panels and posts, incrementally, 2 feet at a time,” Hurst says. “Then you take the excavator and push the panel down with the bucket.”
Marcus Construction used two Komatsu PC240 Excavators, from General Equipment of Fargo, North Dakota, for the project.
The Slide Rail System has the capacity to reach 32 feet.
“Because it’s a component system, the panels and corner posts have a set maximum weight for what would be the largest piece,” McRay says. “You can match your excavator capacity to the heaviest component you need to lift. That is helpful, because it brings in more mid-size excavators that can be used to install the Slide Rail System.”
The benefit, McRay continues is that a contractor may have midsize excavators as part of its fleet, which can be used, eliminating the need to rent a large excavator or crane.
“There is a definite technique to installing slide rail,” McRay says. “Our installers are good at teaching the contractor’s crew.”
Usually, the first day on site goes slowly, Hurst says. Everything must be squared.
“Once the operators get the technique down, they take ownership of the installation of the system, and by the third day, our installer steps back and troubleshoots or solve problems,” Hurst says.
Efficiency Production sent an advisor to help install the versatile universal Slide Rail System at the fertilizer job site. “They were very helpful,” Roediger says.
Once the track was removed, crews excavated under the tracks, with the site shored. After the pit was dug, Marcus Construction poured the concrete walls.
“It was a two-stage process,” Hurst says. “They dug the deeper excavation, poured the taller walls, removed the Slide Rail, turned 90 degrees and put in a shallower Slide Rail shoring system.”
The second area was about 6 feet deep. The crews tied that vault to the original one. The shoring portion of the project lasted 45 days from start to concrete pours.
“One of the important advantages of a Slide Rail System over open-cutting is that there’s no over-digging; the excavation walls can be cut exactly vertical,” Hurst explains. “The ‘positive’ shoring system also creates a much tighter work area.”
A Variety of Work
Founded in 1956 by Carl Marcus, Marcus Construction remains family owned and operated and specializes in agricultural and commercial projects. Carl’s son, Ross, serves as CEO and his son, Taylor, joined the company in 2017. The company takes a team approach, with a designated project manager and onsite superintendent, to deliver quality work, whether for private or public customers.
The agricultural division builds dry fertilizer, chemical and seed buildings, inland and river terminals, and bulk material buildings, across the United States and Canada. The division also provides renovation services. The commercial side builds office buildings and retail, healthcare, education, worship facilities, and heavy industrial buildings mostly in a five-state area, including Minnesota, Iowa, North and South Dakota, and Wisconsin.
Marcus Construction offers pre-construction services, and design-build and general contractor delivery methods. The North Prairie Ag project was a design-build project. The company can handle a variety of scope of work including site work, permitting, soil testing, layout and planning, geotechnical engineering and civil packages.
A culture of safety pervades all Marcus Construction projects. Certified safety professionals manage the company’s safety program. Superintendents, such as Bob Gaddy at the North Prairie Ag project, focus on ensuring all safety measures are taken. Marcus Construction has used the Efficiency Production Slide Rail System on prior jobs.
Efficiency Production, “America’s Trench Box Builder,” is an Arcosa Shoring Products company. In addition to the Slide Rail Shoring system, it offers trench and manhole shields, hydraulic trench shoring and excavation support equipment.
“Efficiency’s versatile trench shielding and shoring systems are designed specifically for safe and cost effective installation of utility systems and infrastructure improvements,” McRay concludes.