Installation Process of Ground Anchors
The entire procedure which is adopted for the installation of a ground anchor is described below in steps.
First of all, Holes of the required size are drilled with the help of a drill rig, etc., at the locations selected for the installation of anchors. The depth of the holes will be the desired depth as the design depth. Holes will be drilled with or without casing pipes, either vertically or at an inclination as required.
The anchor tendon is inserted centrally into the hole.
A grout, usually cement, is pumped into the space left between the tendon and the hole at predetermined grouting pressure. The pressures vary for the primary grouting and the secondary grouting.
Usually, a sheath is provided around the tendon in the secondary grout area to protect it from corrosion. If a casing pipe is used in drilling the hole, it will be withdrawn during grouting. The grout is finally allowed to cure.
A reaction and locking mechanism are connected on the ground surface or on a structural surface, which is called an anchor head.
Extended tensile stress is applied to the anchor by a hydraulic jack, which is greater than the design load. The value of this tensile stress usually varies from 1.25 to 2 times the design load of the anchor. They may sometimes be pre-stressed to control the longitudinal movement.
When the load is applied to the anchor, the lock-off system is engaged, and the applied tension from the jack is released.
Audio of Installation of Ground Anchors