A senior laboratory technician at Structural Soils, recently attended a two-day course on practical rock mechanics testing at the University of Portsmouth. The course covered extensive testing and analysis of rock samples to a range of International Society of Rock Mechanics standards.
They learned some new ways to prepare small-diameter rock cores for shear testing: something we have been unable to do in the past. In addition, we will adapt some of the safety procedures he saw to minimise the rock shrapnel generated during compression testing.
The Bristol laboratory has recently acquired two new pieces of equipment that expand our rock testing capabilities to include slake durability and Cerchar abrasivity indices meaning we can now offer these testing services in house.
The slake-durability index measures the resistance of weak rocks, for example, shale, mudstone, siltstone and other clay-bearing rocks, to weakening and disintegration owing to cycles of drying and wetting.
The Cerchar abrasivity index is widely used as a measure of how abrasive rock is and is directly related to the wear of the cutter head in tunnel boring machines and the excavator bucket teeth in dredging operations, for example, the type of equipment used when building the electrical interconnector underwater and underground between France and the UK via the island of Alderney.