Fuzzy comprehensive risk evaluation of roof water inrush based on catastrophe theory in the Jurassic coalfield of northwest China

摘要

The risk assessment of roof water inrush is of great significance for sustainable development of mine and ecological environment Taking the Jurassic coalfield in northwest China as an engineering background, we firstly selected nine indexes influencing roof water inrush based on three essential conditions with the water source, the water inrush channel and the mining space, i.e., unit water inflow, flushing fluid consumption, aquifer thickness, effective aquiclude thickness, lithological association of the effective aquiclude, inclined length of coalface, buried depth of coal seam, mining thickness and advancing speed of coal mining, and then established the hierarchy structure model for mutation evaluation of roof water inrush. Secondly, the expert scoring method and trapezoidal fuzzy distribution were chosen to construct the initial fuzzy membership function based on the characteristics with fuzziness and mutability of roof water inrush. Thirdly, based on quantized recursion operation with the normalization formula and the (non) complementarity principle, total mutation membership function value was calculated, and the water inrush risk grade was determined. Eventually, the proposed method has successfully predicted the water inrush risk in the first mining face of Jinjitan coal mine. The research achievements provide an important reference for the sustainable development of the Jurassic coalfield.