Development of high pretensioned and intensive supporting system and its application in coal mine roadways

In view of the features of complicated and difficult roadways, the present problems on rock bolting technique were analyzed, and the high pretensioned and intensive supporting theory was put forward. The initial supporting stiffness and strength of bolting system should be increased largely to control the dilatant deformation and maintain the integrity of surrounding rock. The high pretensioned and intensive bolt and cable system was developed, and the mechanical properties of the bolting components were obviously improved. This system has been successfully applied in the 1000m deep entries in Xinwen coal field, and the entries affected by intense mining activities in Lu’an coal field. The deformation of the entries was reduced by a big margin. This system provides an effective supporting form for complicated and difficult roadways.