Experimental Study on Stress Evolution and Microseismic Signals under Vibration Conditions of Coal during Excavation and Subsequent Waiting Time

Figure 12

Microseism signal change trend of energy and event numbers at a range of excavation speeds: (a) microseismic sensor 1# at excavation speed ; (b) microseismic sensor 2# at excavation speed ; (c) microseismic sensor 1# at excavation speed ; (d) microseismic sensor 2# at excavation speed ; (e) microseismic sensor 1# at excavation speed ; (f) microseismic sensor 2# at excavation speed .

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