Abstract
The bond strength of rock bolt must be evaluated appropriately for design of tunnel support. In the present study, the pullout tests were conducted in order to obtain the bond strength of various rock bolts, which includes higher stiffness or fiber-reinforced plastics (FRP). Especially, the bond strengths of various rock-bolts in early age were evaluated. From the test results, the bond strength of steel rock-bolt in different mechanical properties was almost equal. The different materials were so influenced factor on the bond strength of rock bolt.
