Hardman Construction installs different types of drilled and driven earth retention systems including steel sheeting, soldier piles and wood lagging, tangent augercast walls, soil nail walls and earth anchors. Installed in all types of soil to provide horizontal and vertical restraint of earth, water or existing structures during excavation and construction of below-grade facilities, our earth retention systems can be installed in top-down, cantilevered, braced or tied-back fashion to meet our clients’ specific needs.
Soldier piles and wood lagging systems are commonly used and are extremely cost efficient. Soldier piles are driven or predrilled at intervals along the wall’s baseline. If a predrilled approach is used, holes are drilled, grout is placed and an H-pile is installed in the hole, thereby providing a vibration-free installation. As the excavation in front of the wall proceeds, wood lagging is installed between the soldier piles in lifts. Tieback anchors may be installed and stressed to provide lateral restraint.
Tangent augercast walls are constructed by drilling low-vibration augercast piles at spaced intervals followed by installation of additional augercast piles between those spaces. This forms a continuous wall, sealing off the excavation. While these walls may be tied back or internally braced, tangent augercast walls are often a good solution when seeking a vibrationless earth retention system adjacent to existing structures or critical utilities.
Soil nail walls are an excellent solution when vibration-free foundation installations are required such as construction next to existing structures, reconstruction projects and reinforcement of existing embankments. Soil nail walls are installed in a continuous excavation method whereby shallow 3' - 6' vertical cuts are made in the soil, holes are drilled for the nails, soil nail tendons are installed and grouted, a shotcrete layer is applied and bearing plates and nuts are attached. This process is repeated until the final grade is reached. The grouted nails increase the shear strength of the overall soil mass and limit displacement during and after excavation.
Earth anchors can be used to limit lateral movement of retention walls or soils that have been vertically shored, allowing the face of the soil to remain free from obstruction. Earth anchors are beneficial when conventional tiebacks or excavation with internal bracing cannot be used. A variety of materials, designs and installation lengths are used depending upon the load to be carried and the bearing strength of the soil.