LARGE DEFORMATION ANALYSIS FOR ROCK EXCAVATIONS - A NUMERICAL STUDY

A rock mass responds to excavation according to the properties of the intact rock, the network of contained discontinuities and the suscepti bility of the rock mass to weathering. Large deformation often occurs when one of these components causes the rock mass to have a low streng th relative to the stress conditions. Analysis of such large deformati ons forms a significant feature of current numerical modelling in rock mechanics. A practical large deformation problem of roadways in a coa l mine is described, demonstrating the requirements for improving nume rical techniques. The development of a numerical model is then summari zed with particular attention to several concepts pertinent to large d eformation analysis in geomechanics. A numerical case study is present ed in which the developed finite-element model is used and the results are compared with the in-situ measurements. Conclusions are drawn for rock engineering that are relevant to both civil engineering and mini ng engineering projects.