LAUSR

A stability evaluation model, with an assessment system comprising 14 main indexes, is established by applying fuzzy mathematics and euthenics. The indexes are roughly quantized by the fuzzy membership degree. Analytic hierarchy process is utilized to assign the weight of each index. The stability level of a gateway in a mine with closely spaced coal seams is calculated by comprehensive correlation analysis based on the euthenics theory. As an index representing the gateway stability, the stability level can indicate the effect the adjustment of the gateway parameters will have on gateway stability and point out the areas to be improved for optimal control of the surrounding rock. In a case study, the optimization technology was applied to gateways in the Xiandewang coalmine, China, whereby the stability of headgate no. 1720 and tailgates no. 1925 and no. 1727 was enhanced by applying the stability-level evaluation analysis. Through the engineering application developed here, utilizing indexes characterizing the improvement in gateway stability levels changes to the stress disturbance and adjustment of the construction factors can effectively improve the gateway support when the natural attributes are similar or unchanged.