Cable bolting is an established technique used extensively for reinforcement of the rock mass adjacent to surface and underground rock excavations. Cable bolts are long, fully grouted, untensioned reinforcing elements. The objective of cable bolting is to improve the shear and tensile strength of the rock mass.
In some cases normal cable bolting is too stiff a reinforcement method and it is unable to survive large deformations. For example, reinforcement of a highly stressed and broken rock mass requires a more flexible cable bolt. A yielding cable bolt would be an obvious solution in these cases. This two-year research project has been studying the viability of this solution. The project started in 1993 with a short preliminary study. A more detailed literature review has been carried out during 1994 and 1995. According to the review, the yielding cable bolt would provide major advantages in mining operations using cable bolting with a skin or surface support.
The successful development of the yielding cable bolt requires a basic understanding of cable/grout/rock interactions. Numerical modelling methods should be applied in analyzing the assumed behaviour of the yielding cable bolt to assist in the design of the required laboratory and field tests.