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Abstract Rock mass damping ratio，as an important dynamic parameter of rock mass，is widely tested by block excitation testing method which costs much. Blasting excitation is a simpler and more efficient method than block excitation for rock mass damping ratio. It needs to consider influence of geometric damping induced by geometric diffusion of energy. Formula of calculating rock mass damping ratio in attenuation of surface wave is derived with viscoelastic model. In Haiyang Nuclear Power Plant，a test consisting single hole and porous blasting excitation was conducted and the test data were analyzed by wavelet packet. In order to verify result of blasting excitation test，block excitation method was tested under the same condition. Results show that the ratio from blasting excitation test is larger than that from block excitation test，and the ratio from blasting excitation test decreases with the increasing distance between explosion source and measuring point. Moreover，the rock mass damping ratio was affected by blasting vibration frequency. Comparison of experimental results showed that rock mass damping ratio could be obtained through blasting vibration information.
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Received: 31 December 2012
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2014, Vol. 33 
