Study on key supporting techniques of large cross-section roadway in compound mudstone roof

The roadways in compound mudstone roof are apt to cause collapsed accidents during the excavating or service periods. Based on the field investigation for quantities of compound roadways in coal mines, the corresponding compound mudstone roof is analyzed and categorized. By use of the mechanical model for the roof deformation, the reasons for caving are deduced theoretically, and the key supporting technology combining with cable truss support, bolt and anchorage cable, and applying high pre-tightening force at the initial stage, which is put into application on the large cross section roadway No. 21101 of a coal mine. Besides, the final scheme and parameters are determined by numerical simulation according to geological conditions, and the experimental results show that this set of supporting technology is effective to safety and stability for the complicate roof.