Experimental Study on Failure Law and Mechanism of Red Sandstone under Ultrasonic Vibration Excitation

Table 3

P-wave velocities after ultrasonic vibration for various periods of time.

Monitoring location	Initial wave velocity	40 s	60 s	80 s	100 s	120 s	140 s
Section A	4875	4323	4121	3521	3156	2810	2741
Section B	4863	4791	4653	4355	4020	3766	3564
Section C	4871	4869	4866	4860	4842	4836	4833
Average	4889	4968	4998	4756	4531	4378	3646