Abstract:
The supporting efficiency of the filling roadway during longwall-roadway cemented backfilling process greatly affects the speed of roadway driving. In order to simplify the support during the mining process when both sides of the filling roadway are in the dynamic combination of coal body-coal body, filler-coal body, and filler-filler surrounding rock, this paper uses numerical simulation to obtain the stress evolution law of the coal and the backfill in a single mining cycle. According to the different composite bearing characteristics of the coal and the filling body around the filling roadway, three supporting schemes are designed and the supporting effect is analyzed. It is found that at different stages of a single mining cycle, the coal body is the main bearing part of the composite load-bearing system, with the maximum vertical stress of 34.4 MPa and the stress concentration coefficient of 2.33. The vertical stress range of the filler is about 0.5 MPa to 2.13 MPa, and the change range is small. In the process of tunneling, when the support on the side of the filling body is reduced, the section shrinkage rate of the filling roadway in the three states is 2.84%, 4.38% and 13.33%, respectively. In other words, the reduced support has little influence on the roadway deformation when the coal-filling body compound bearing capacity exists in a single mining cycle.