Slide Rail Systems Offer Cost-Effective Trench Safety Option

By Jeff Griffin, Senior Editor | April 2010 Vol. 65 No. 4

For excavation projects requiring manned entry, shielding and shoring trench walls is a major cost. Material and labor prices escalate as excavations cover more area and become deeper.

On many large projects -- especially long runs of large-diameter pipe installation -- slide rail systems have become the preferred method of preventing the collapse of trench walls. Proponents say that in most cases, slide rails can be installed faster and more economically than conventional methods.

A slide rail system is a component shoring system comprised of steel panels similar to trench shield side walls and vertical steel posts. It is installed as the trench or pit is excavated by sliding the panels into integrated rails on the posts -- either double or triple rails depending on needed depth -- then pushing the panels and posts incrementally down to grade as the pit is dug.

Modular slide rail systems may be used in a variety of configurations without cutting or welding. They do not require interior walers or beams which provides more working space in the excavation. Slide rail manufacturers say the systems can reduce shoring costs from 30 to 60 percent compared to conventional methods.

Representatives of three leading slide rail manufacturers recently commented to Underground Construction on the technology and the advantages it offers.

Efficiency Production, James McRay, director of marketing and media: “Slide rails have become a very popular alternative to applications that would require tight sheeting and are most effectively used in very encumbered areas where access to all four sides of an excavation is not possible. Because slide rails are comprised of component pieces, the entire system can be installed with access to only one or two sides. In many cases, traditional trench shields and shoring is just unfeasible, either due to the restrictions of excavation site, or the limitations of the excavator and other equipment. In those instances slide rails may be the only option. This is certainly true for very deep excavations, or when it is necessary to shore all four sides of an excavation.

“There are differences among the slide rail systems available today. The biggest is in applications that require a cross brace or spreader system and tend to vary widely between the manufacturers. Efficiency Production’s system of cross brace support utilizes parallel beams that pin in place standard trench box spreader pipes.