Stress Recovery Law of Six-Direction Pressure Sensor Embedded in Rheological Rock

Rheological stress recovery(RSR) method was suggested to measure the in-situ stress and disturbance stress of rock mass involving time-dependent behavior. It was carried out by embedding six-direction pressure sensor into the borehole of surrounding rock with grout filling. Mastering the measured stress recovery property of the sensor in the rheological rock mass is one of the key problems for the RSR method. Based on the measurement principle of RSR method, the numerical method is adopted to simulate stress measuring process of RSR method employing the six-direction pressure sensor. The recovery law of measured stress of six-direction pressure sensor under different rock types, surrounding rock grades, rheological models and geostress states are studied respectively. The simulation results show that the stronger of the rock rheology, the shorter of the time required for the sensor stress recovery to the final stable value, and the higher of the stress recovery degree of the sensor.