Large scale testing of surface support

Abstract

Ground support for dynamic conditions must be able to withstand the associated loads and deformations and the support scheme must work as a system. In order to prove the suitability of such support systems with high-tensile steel mesh and bolts, and also to analyse their bearing behaviour, a large-scale test setup was commissioned in Walenstadt, Switzerland. On this test rig, it was possible to apply large energies on variable ground support schemes with variable bolt patterns and meshes with a total support area of 3.6 m x 3.6 m. The test site is instrumented by load cells, high-speed video analysis and accelerometers. In this paper the analysis of the load cells, the accelerometers and the high-speed video cameras is given, and results are discussed. It could be shown that a combination of high-tensile steel mesh with a specific bolt pattern can result in high energy capacity surface support. Distribution of the impact loads during the stoping process to the different elements of the bearing support system depends on the strength and flexibility of the mesh and the bolts resistance and his pattern.