Deformation characteristics and separation monitoring of layered roof roadway supported with bolts and cables

From the analysis of characteristics of roof separation and the principle of roof separation observation, deep and shallow basis points of indicator should be set on the same level respectively with anchor end of cables and bolts.The strata to install the deep basis points of indicator may take place displacement in all kinds of roadway affected by mining action.Except for roof separation observation, roof subsidence observation must be conducted.Only combined these two observations, the effect of bolt supporting and surrounding rock stability can be evaluated more objectively.Based upon the comprehensive analysis of different roof strata occurrence conditions, critical value of roof separation for all kinds of bolting support roadway was proposed.