Study of model test on mechanism of bolt in deep tunnel with high geo-stress

How to keep the stability is becoming the key point in the design and construction of deep tunnel with high geo-stress, it needs a higher standard to its support design. Based on the rock character of a deep tunnel in Chongqing, special equipments of similar materials and model test are developed to reproduce the whole process of progressive failure of surrounding rock with different supporting conditions. Through solving a series of technological matters in execution and installation and testing, by using of the strain measure technology, the strain of key parts of the surrounding rock and the bolt under different supporting conditions is measured and then the variability of the stress of surrounding rock and the variability of the axial force of the bole are studied. Through the physical model test, the failure law of the surrounding rock in high in-situ stress and variation of the system characteristic parameters of surrounding rock and support structure system are obtained.