Definition - What does Rock Bolts mean?
Rock bolts are long bolts that anchor or support excavation by penetrating deep into the stronger portion of the rock and holding fast. Once the rock bolt is anchored, a compression force is set up into the surrounding rock. Trenchless methods of pipeline installation such as microtunneling and pipe jacking require excavating launch and exit pits for workers to operate equipment from.
Unstable rock formations can be dangerous for workers and equipment if they fall. Rock bolts can be used to hold up excavated pits by anchoring them into loose formations along with strong meshing.
Trenchlesspedia explains Rock Bolts
Rock bolts should be strong enough in order to support the dead weight of the loosened rock. Geological discontinuities become less with depth, but in-situ rock stresses increase with depth. Rock bolts have to be selected depending on the loading condition of the rock mass. The rock bolt should have strength higher than the load it has to bear. Rock bolting is carried out by arranging the bolting pattern in such a way that the rock structure is well supported.
Each bolt is anchored and tension is applied to the bolt to bring the rock under compression parallel to the bolt.