Similar-material, composed of different raw materials with different properties, is similar to the physical and mechanical properties of geotechnical media, in which raw material proportioning is an important means to control the performance of similar-material in physical simulation. On this basis, a new fluid–solid coupling similar-material was developed through proportioning tests, in which similar-material is mixed with river sand, calcium carbonate, talc powder, white cement, vaseline, antiwear hydraulic oil. The optimum proportioning test development process was established. First, the proportioning test scheme was designed based on the orthogonal test. Subsequently, test specimens were produced to obtain parameters such as density, compressive strength, tensile strength, and permeability coefficient. Then, by increasing the ingredients of the proportioning, the evolution law of parameters was obtained by range and variance analysis. Finally, four multiple linear regression equations between the parameters and similar-material ingredients were obtained, and the optimum proportioning of ingredients was further determined for different requirements. The results indicate that the selected raw materials and their proportioning method are feasible, and the results were also verified in a coal mine floor water inrush by physical simulation test. The experimental development process of a fluid–solid coupling similar-material can provide a reference for similar-material under different demand conditions.

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.