Research On Support Technology For Soft Rock Roadway Crossing Fault Fracture Zone

Under the influence of geological disasters,the difficulty of support in soft rock roadway is greatly increased.It is of great practical significance to study the support technology of soft rock roadway crossing fault fracture zone.In this paper,based on the fault zone of soft rock roadway face in 3-1 coal return airway of Hongqingliang Coal Mine,the research work is carried out by comprehensive means of field investigation,indoor experiment,theoretical analysis,field measurement,numerical simulation and dynamic monitoring.The main research contents include:?1?Through the field investigation,advanced geological prediction and drilling detection,the characteristics of the fracture zone are determined.The rock physical and mechanical properties and composition of the rocks around the fault are obtained by the indoor physical test and X-ray diffraction experiments,which provide effective data for the analysis of the surrounding rock failure and numerical simulation.?2?Using the borehole peep device to test the range of the loose circle around the fault zone in the soft rock roadway,then predicting the range of the surrounding rock loose zone in the fault location by grey theory,it is to provide reliable basis for the design of supporting parameters;?3?Analyzing the surrounding rock failure mechanism from different aspects,and design support parameters based on loosening circle theory.The program is proposed that bypass construction,pre-reinforcement with grouting"cement+water glass",variable cross-section+“cable+net+rope+spray+U-steel frame+respray”;?4?It is carried out numerical simulation analysis by using large-scale finite difference software FLAC^3D.A comparison model is established to explore the rationality of the bypass design and the feasibility of support scheme,aiming at the stress,the plastic zone,the displacement and the supporting structure.?5?Carring on industrial test and dynamic safety monitor in field which include the amount of roof slab,the actual force of the cable and the convergence of the surrounding rock in the fault zone of soft rock roadway.The monitoring results show that the roadway support effect is good.