Abstract During the excavation of deep rock,the strain energy release of surrounding rock is one of the incentive reasons which will lead to the destruction of rock,while there is a big difference in strain energy release rules under different excavation methods. By theoretical analysis,discussed the mechanism of energy conversion and distribution of drilling and blasting method and TBM excavation,and field monitored and comparison analyzed the Jin-ping II Hydropower Station rock vibrations caused by TBM and drilling and blasting method in tunnel excavation to discuss the strain release process and characteristic. Studies show that,strain energy stored in rock mass released fleetly when drilling and blasting excavate the rock in high in-situ stress,and vibration energy induced by the strain energy is roughly equal to the vibration energy induced by blasting energy,besides,the strain energy releasing of MS1 segment is about 50% of total energy releasing; However,the strain energy of rock mass released slowly by the quasi-static method under the TBM excavation,Almost all turning into the potential energy of the surrounding rock,doesn?t cause the dynamic response. In the same conditions,the range and the rate of strain energy release caused by drilling and blasting excavation is larger than TBM excavation,which led to more high-grade rock burst,but in the condition of TBM excavation,the destruction phenomenon represented by spalling and flaking is more frequent.
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