In situ bond strength testing of Australian cable bolts

Testing of axial load transfer of various Australian cable bolts has been conducted in overseas laboratories within the last two years (Thomas, 2012). The comparative laboratory testing determined that nutcaged cables and indented wire cables provide stiffer and higher capacity bond strength compared to plain cable. Laboratory studies have limitations in terms of rock strength and installation practice but have the benefit of controlling the type of load applied during the test. In situ cable bolt tests were conducted underground using common installation equipment, resin capsules instead of cementitious grout where relevant, and in a typical coal mine roof. In situ testing methods included anti-twist methodology similar to that used in laboratory tests.