Soil and Rock Anchors
Anchoring is a common geotechnical construction technique to provide vertical, horizontal or sliding resistance. The applications are widespread and there are many different systems available. These include mechanical, resin, cement grout and helical systems to transfer the load into the ground or concrete. After installation the load transfer to the structure can be passive or post tensioned to provide active resistance. Installations have been performed up to 2000 kip capacity.
TerraFirm owns special equipment for limited access and difficult drilling conditions for soil and rock.
Uplift Anchors are installed where vertical restraint is necessary. Common uplift applications include subsurface basins, coffer dams seals and dams. They are also used to manage overturning or pullout loads on towers or guys.
Horizontal or Inclined applications for rock and soil anchors, also commonly called Tie Backs are widespread. Most common are to resist lateral earth pressures for excavations, either temporally or permanently. They are used in many aspects of construction and for remedial work. Typically horizontal anchors are post tensioned to apply a preload or to provide active restraint in remedial applications. Landslides can also remediated with high capacity anchors and thrust blocks to resist a rotational failure.
Sliding resistance can be augmented by utilizing anchors to exert a substantial normal force which increases the resistance to sliding. Since the 1970s anchors have been installed through dams and post tensioned to increase the dams ability to resist overturning and sliding.
Roof Bolts are used in mining or tunneling applications to reinforce the roof and connect varying rock formations. Many applications for roof bolts use a mechanical anchorage system or a specially designed polyester resin cartridge system. Typically large areas are bolted with a relatively close spacing. TerraFirm’s staff has performed projects where 100 units per shift were installed.