Faster Excavation Shoring with High-Load-Capacity Hydraulic Struts

Hydraulic shoring systems can shrink project timelines, cut labor costs, and increase safety.

Installing conventional excavation shoring systems for a large excavation can bust budgets and schedules. Fabricating and welding steel beam walers and pipe struts is slow, tedious, and potentially dangerous work. For deep excavations, installing welded shoring at every level consumes even more time and man-hours. High-load-capacity hydraulic struts offer the same level of shoring protection while slashing installation time and boosting safety.

These heavy-duty steel struts have three main parts: A base adjustable hydraulic ram unit that provides up to 1 meter of length adjustment for a precise fit; one or more bolt-together extension units; and end bearing plates that can be secured against a variety of working surfaces. They can span an excavation as a direct support between concrete capping beams in basement-type applications or steel walers, modular hydraulic bracing systems or slurry walls.

The struts are available in multiple sizes, from 150 tonnes to 750 tonnes, with clear spans up to 157 feet, which enables companies to design an excavation shoring system that’s customized for the excavation dimensions and the expected loads. United Rentals is the only company in North America that offers 750-tonne struts, which enable large clear spans and are capable of handling the high loads often seen in deep excavation shoring.

Big struts, big benefits

High-load-capacity hydraulic struts require little to no fabrication or welding. They can be assembled offsite, then delivered, lifted into place, connected and pressurized in just a few hours. Compared to welding steel pipe in place and using manual jacks with steel shims for pressurizing, using hydraulic struts drastically reduces installation time while minimizing hazardous tasks that may put workers in harm’s way.

The time savings can be dramatic. On one infrastructure project, a hydraulic shoring system designed by United Rentals and consisting of hydraulic struts and modular hydraulic braces cut shoring time by two-thirds and saved hundreds of thousands of dollars in labor costs.

Removing the struts is easy. Connecting two hoses to a power pack and pulling a lever releases the pressure. It takes about 30 minutes to depressurize the struts and lift them out of the hole and into a truck. There’s no leftover material to contend with. By contrast, to relieve the pressure on welded pipes and remove them, a worker must cut them out with a welding torch, a process that poses significant hazards. Leftover steel must be disposed of or stored.

Another significant advantage of high-load-capacity hydraulic struts: Load pins can be installed inside the struts by the temporary equipment vendor, allowing project team members to wirelessly monitor the load applied to struts in real time. Configurable alerts raise awareness of substantial load fluctuations.

Designing a hydraulic shoring system

Designing a high-load-capacity hydraulic shoring system based on the expected load, including surcharges, is a job for engineers. The size of the struts and the way the components are bolted together determine their load capacity.

United Rentals pioneered the use of high-load-capacity hydraulic struts in the United States and leverages that experience, and the expertise of in-house Registered Professional Engineers, to design hydraulic excavation shoring and bracing systems for each customer’s application. A United Rentals installation adviser can help ensure that the struts are installed according to the engineered plans.

If a contractor already has a shoring plan in place that calls for welded steel struts, United Rentals can review the plan and advise whether high-load-capacity hydraulic struts could deliver efficiencies and cost savings.

High-load-capacity hydraulic struts are the way of the future for supporting large or deep excavations. United Rentals has the expertise to design shoring systems using these struts and the scale to source them quickly, allowing customers to claw back days -- or even weeks -- in a project schedule and begin work in an excavation sooner.

To inquire about hydraulic shoring and bracing solutions for your next excavation, contact the United Rentals Trench Safety team.