Load Transfer Behavior of Fully Grouted Cable Bolts Reinforced in Weak Rocks Under Tensile Loading Conditions

摘要

To enable a better understanding of the load transfer performance of fully grouted cable bolts, a new laboratory short encapsulation pull test (LSEPT) unit has been designed and constructed. With this unit, both peak and residual capacity can be assessed over a relatively large pull-out displacement range of 100 mm. Various cable bolt failure modes, including relative slippage along the cable/grout and grout/rock interface, can be studied. Both a modified and a plain strand cable bolt confined in a material having a low strength of 8 MPa were tested. Within this testing process, the impact of the design of the bearing plate was considered that was found to alter the failure mode of the modified cable bolt. Other factors are considered, including the influence of borehole diameter, cable surface geometry, and sample strength on the axial performance of cable bolts.