ABSTRACT
Two rockbolts groups are ungrouted mechanically and grouted rockbolts. In ungrouted rockbolts the load and deformation characteristics of the system depend upon the behavior of the anchor, washer plate and bolt head and as well as upon the behavior of the bolt shank. The rock-reinforcement interaction concepts are not difficult to use for these types of rockbolts. It is very complicated to use for grouted rockbolts and there is not a comprehensive analytical method to characterize these types of rockbolts. This is because they do not act independently of the rock mass and hence, the deformations of the rock mass and reinforcement system can not be separated. In this paper, Rockbolt behavior is modeled for both mechanical and grouted rockbolts by FLAC and the effect of rockbolt presence is investigated in different states of stress. A comparison is made between the results obtained from Convergence Control method (Indraratna & Kaiser 1991) and FLAC program (Itasca Consulting Group 1995).
