Prediction on surrounding rock splitting failure range of Baziling forked tunnel

The underground caverns that locate in high geostress are being excavated, the surrounding rock are prone to present longitudinal splitting cracks and lead to rock failure and endanger safety of engineering. Based on the analysis method of stress intensity factor of fracture mechanics, according to the mechanism and spread process of splitting failure, the criterion of splitting failure is set up. The criterion is applied in Baziling forked tunnel. The criterion is programmed into fish and within FLAC3D. At last get the splitting failure range of Baziling forked tunnel. The results show that the criterion can predict the range of splitting failure rather exactly and offer reference to design and construction of similar engineering.