Experimental Study of Single Structure Surface Dangerous Rock Mass Dynamic Characteristics Based on Constant Micromotion

The dynamic parameters of a dangerous rock mass reflect the degree damage structure its surface. There is still an urgent problem to identify based on characteristics constant micromotion at site. To address this problem, method proposed undergoing excitation caused by micromotion: (1) vibration from classified as forced undamped structural with single freedom. ratio amplitude spectrum bedrock defined relative spectrum. first-order natural frequency identified (2) Bedrock source mass. When mechanical wave propagates mass, it crosses porous surface media damage, and scattering occurs. domain changes. center shifts low frequency. By means laboratory model tests, changes in models cantilevered sliding are analyzed. It concluded that theory mechanics, frequencies masses can be obtained their spectra. measurable. macroscopic fractures cannot development fractures. microscopic change high-frequency band. (3) limitations using mechanics or elastic analyze mass; more effective integrate both methods.