EBS’s design-build capabilities can provide our clients with a cost-effective custom shoring solution.
The advantages of using EBS include the following:
- the ability to install in limited access and low headroom
- minimize vibrations and spoils
- in-house engineering team that reduces design time
Our specialty shoring systems include:
Hybrid Soldier Pile and Lagging Wall
Helical piles or micropiles can be used for hybrid soldier pile and lagging walls in tight access/low headroom sites. The system would consist of vertical helical piles or micropiles installed as soldier piles. As excavation operations commence, channels are attached to the micropiles (soldier piles) and lagging is installed to support the excavation. Once a lift of lagging is in place tiebacks consisting of either helical anchors or grouted anchors are installed horizontally to minimize lateral deflection.
HELICAL TIEBACK AND GROUTED ANCHOR
Helical Tieback or grouted anchor walls typically consist of cast-in-place reinforced concrete walls, with spread footings and one or more rows of helical tiebacks or grouted anchors. They are often post-tensioned and generate pullout resistance past the active zone of the soil behind the wall. Grouted anchors or helical tiebacks are typically installed at a 10-15° angle from horizontal but can be installed at steeper angles if required.
An important factor in building tieback walls is the downward component of force caused by the helical tiebacks or grouted anchors. (Each tieback results in a horizontal and vertical component of force in the retaining wall). They must be designed for the weight of the wall facing and downward component of force. As such, an analysis of anchor pullout, lateral earth pressures, overturning stability, sliding and bearing capacity must be undertaken prior to construction. Four of the more common types of excavation shoring are: shotcrete walls, sheet pile walls, soldier pile and lagging walls or braced walls.
Shotcrete Shoring Walls (Helical Soils Screws Or Grouted Anchors)
Shotcrete walls can be created by excavating and installing tiebacks (helical or soil nail), followed by shotcrete in several stages. (A method often referred to as “top-down construction”.) This shoring can be completed in tight access low headroom sites and on the interior of structures.
Tiebacks For Sheet Pile Walls
Sheet pile shoring systems are constructed by driving or vibrating continuous corrugated sheet piling through the ground from the surface along the perimeter of an excavation. After sheet piles have been installed, an excavation is made to the top row of the tiebacks. Tiebacks can consist of helical or grouted anchors. Once the tiebacks have been installed, a steel waler is placed over the anchors and attached to the sheet pile. The process is then repeated from the second and subsequent rows of tiebacks.
Projects
View case studies involving specialty shoring applications on the projects page.