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Abstract The vibration characteristics of surrounding rock induced by the excavation of tunnel under high in-situ stress are studied with combined method of theoretical analysis，numerical simulation by dynamic finite element method(FEM) and verification with monitored field vibration data. It is found that the vibration induced by the excavation of tunnel under high in-situ stress is the result of superposition of blasting-induced vibration(BIV) and the transient unloading of in-situ stress induced vibration(DUIV). The study reveals that，under low in-situ stress condition，the vibration in surrounding rock is mostly induced by blasting load. Under high in-situ stress condition，the DUIV could become absolutely the main factor of total seismic wave induced by the excavation of tunnel with method of drilling and blasting. In the end，monitored vibration induced by the excavation of tail-water and inlet water tunnel in Pubugou Hydropower Station，Shichuan Province，China，is presented as a verification，which is corresponding to in-situ stresses of 10 and 20 MPa，respectively.
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Received: 23 April 2007
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