Research And Application Of Anchorage Support Mechanism In Roof Of Weakly Consolidated Soft Rock Joe Top-coal Roadway

This paper analyzes the deformation and failure law of top roof of top coal Roadway which takes the 11301 working surface air return roadway of Hongqingliang Coal Mine as a case, by combination of mechanical test, theoretical analysis, numerical simulation and field monitoring. The paper puts forward the mechanism of bolt and cable on the roof of the soft coal caving roadway, and provides the theoretical basis for the optimization of the support of the roof coal roadway. The main research contents and conclusions are as follows:(1) Through indoor test, measuring 11301 working face gateway top-coal overlying mudstone mechanical parameters and different depth,analysis of roof near coal bed mudstone and coal shale mechanical properties, combined with rock water immersion test analysis that the working face supporting top-coal roof mudstone with typical soft rock properties of roadway, the roof borehole TV detection found that 11301 working face supporting roadway roof strata appear in the mudstone part top-coal abscission, mudstone layers obviously.(2) Through building the coal roadway structure mechanics model,gives the help coal under the action of horizontal stress expression of coal bending moment, the moment weaken the effect of vertical stress on top-coal, shows that weak cementation of soft rock supporting caving roadway caving has a promoting effect on roof stability.(3) According to roof strata stress analysis, through theoretical analysis on coal beam and YanLiang elastic modulus ratio as the top-coal and nearly coal shale is the basis of abscission layer, obtained considering for coal under the action of the bending moment of the top-coal caving and nearly coal shale expression, the maximum tension stress as roof failure criterion.(4) The numerical simulation results show that the safety and stability of the roof slab can be increased by adjusting roof coal seam thickness, 11301 return wind is suitable for roof coal thickness 1.5-1.75 m. For top-coal stable occurrence, and the roadway roof stability has a promoting effect on top, put forward suitable for weakly consolidated anchorage support of soft rock supporting caving roadway roof design of"shallow reinforcement beam model.(5) "Based on" shallow reinforcement beam model analysis, weak cementation soft rock roadway roof bolt support top-coal main role is the anchoring of top-coal and nearly coal shale, making it the reinforced beam, equivalent increase anchor solid elastic modulus, increase the anchor solid strength, to provide a stable foundation for anchor cable.According to the model analysis, the optimization of the support scheme of 11301 working face is optimized, and the site application is good.