Experimental Study on Effect of Reducing Mine Pressure by Cutting Roof Strata on Failure Zone Depth of Coal Seam Floor Under Confined Aquifers

To study the effect of reducing mine pressure by cutting roof strata on the depth of floor strata failure zones above the confined aquifers, a simple confined aquifer simulation device was developed based on a two-dimensional similar simulation test bed. Stress and displacement were respectively monitored by dynamic strain gauge and total station electronic distance meter. The variation of stress field in surrounding rock and the failure depth of floor strata were got under the conditions of both cutting roof strata and conventional mining conditions. The test results show that there is little difference in fracture conduction zone damage near water body between the two conditions, and the variation trend of the monitored stress is similar, while the stress disturbance intensity is different. The floor failure depth without roof cutting is greater than that under roof cutting, which indicates that the reasonable design of roof cutting can reduce the failure depth of floor to a certain extent.