A splitting failure criterion of surrounding rock mass in depth of high in situ stress region and its engineering application

摘要

During excavating the underground openings, a large range of longitudinal splitting cracks zone appeared in the rock pillars between the main house and transformer house because of the deep embedded and high in-situ stress surrounding rock masses. It endangered the stability of engineering. The test of brittle rock was carried for studying the extending process of splitting cracks and the mechanical mechanism of split failure was obtained. Starting from the perforation mechanism of splitting cracks, according to the extending process of splitting cracks, the criterion of splitting failure was established based on analysis of fracture mechanics. The criterion was applied in underground openings of Er’tan Hydraulic Project. The splitting failure zone was obtained by making use of simulation analysis. By contrast between simulation and in-situ results, it showed that the criterion could predict the range of splitting failure exactly and offer reference to design and construction of similar engineering.