Numerical Modelling of Fully Grouted Rockbolts Subjected to Shear Load

Excerpt

Rockbolts are often installed into the rock masses as a reinforcement structure to restrain the rock deformation at the excavation surface in underground excavation projects. When the rock moves towards the excavation surface, the rockbolt elongates, resulting in tension in the rockbolt and compression in the surrounding rock mass (Bobet and Einstein 2011). The most commonly used rockbolt is the fully grouted rockbolt as it has a reliable anchoring system and high bearing capacity (Li and Stillborg 1999). The mortar and resin are often used as the grouting agent and filled in the annulus between the rockbolt and the borehole wall. The load transferring capacity of the fully grouted rockbolt is, therefore, heavily dependent on the bond strengths at the interfaces between the rockbolt and the grout and between the grout and the rock (Hyett et al. 1992; Ma et al. 2014; Nie et al. 2019). …