| In this paper, we make several similar materials of different substances and different proportions, and conduct uniaxial compression test, analyze each group’s tendentious size of occurring rock burst by means of some judgment method. Then we analyze the rock stress situation after roadway excavation by using the finite element analysis software ANSYS, mainly analyze the variation law of the maximum principal stress at each point on a specific path, under the condition of rock without fracture and rock with single fracture when its angle0, length L, width B, distance r change, the specific contents are as follows:(1) Comparative analysis of each material’s ratio E/λ, we choose the similar material of group A3(Colophony:Bentonite=2:1) and conduct the laboratory model test, and reproduce the whole failure process of rock burst, under the condition of single tunnel.(2) Assuming that θ=150°, r=3.0m, L/B=7.5, variable L and B, we come to the conclusions:The maximum principal stress near roadway roof increases with the increase of L; The maximum principal stress near roadway floor decreases with the increase of L.(3) When fracture’s width changes, there is an obvious stress concentration around the end portion of oval fracture, and it does not mean that the wider or narrower of B is, the greater the stress of surrounding rock is. With the increase of B, the maximum value of maximum principal stress around the end portion of oval fracture increase first and then decrease, and it reaches a maximum value when B=0.30m. |
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