Rock bolts are typically installed into pre-drilled boreholes in the rock (although some are self-drill) and grouted into place. Rock bolts are normally un-tensioned but can be post-tensioned. Boreholes are formed using rotary bored and rotary percussive rigs and down-the-hole hammers, depending on ground conditions.
Rock bolts are usually installed on a grid, and transfer loads from the unstable face into the load bearing solid rock behind. This ‘knits’ unstable sections of rock together, preventing movement. Rock bolts are used together with surface retention, such as wire mesh or shotcrete.
We have the capability to install rock bolts and netting using wheeled excavator based machine or tracked Soilmec and Casagrande drilling rigs.