Analysis of physical parameters of materials similar to coal and rock mass based on geophysical model construction of mines.

This paper constructs a geophysical model of hidden disaster-causing anomalies in coal rock for simulation experiments based on the structural design of coal rock seams at the mine working face to study the geophysical response characteristics of geological anomalies in coal rock seams. The material ratio and petrophysical parameters of the coal seam, roof, floor, collapse column, and fault in a mining area in Shanxi were tested using homogeneous and orthogonal test methods, and their petrophysical parameters, such as Vs,Vp, resistivity, permeability, and dielectric constant, were obtained. The coal dust and sand–cement contents are the main factors affecting the wave velocity, whereas the dielectric constant and resistivity are highly influenced by the water content of the material. The response characteristics of the petrophysical parameters of various types of geological structures measured via experiments are consistent with the corresponding geophysical responses of actual geophysical exploration methods. The experimental data were comparatively analyzed with the original coal rock samples and field in-situ probing results, and the best construction ratios of each geological structural unit were as follows: coal seam ratios of 61.11%, 11.11%, and 27.78% were selected for coal dust, sand, and cement content, respectively; sand–cement and gypsum–cement ratios of 2:1 and 2:8, respectively, were selected for the roof; and sand–cement and gypsum–cement ratios of 3:1 and 4:6, respectively, were selected for the floor. The optimal ratios of 75% sand, 10% gypsum, and 15% cement were chosen for the fault; those for the collapse column were 66.7% sand, 6.67% gypsum, and 26.6% cement. This study focuses on the ratios of various geotectonic physical models and their physical properties, it provides data support for subsequent model construction and a good experimental platform for the demonstration of various geophysical exploration methods and techniques. [ABSTRACT FROM AUTHOR]