关键词: 火成岩侵入, 综放工作面, 超前支承压力, 煤体弱化, 变形诱因

Abstract: In order to master the characteristics of mineral pressure manifestations in the comprehen⁃ sive caving working face under the special geological conditions of igneous intrusion, to ensure the rationali⁃ ty of the roadway support，the characteristics of coal body weakening under the influence of igneous rock in⁃ trusion were determined by testing the physical and mechanical parameters of surrounding rock. On this ba⁃ sis, the magnitude and influence range of the peak abutment pressure during mining under different working conditions were theoretically calculated. Furthermore, the control variable method was adopted to adjust the coal body parameters to build a three-dimensional numerical model before and after igneous rock intrusion, and the variation rules of vertical stress at different depths above the working face were clarified. The accura⁃ cy of the research results is verified by field measurement.The results show that the intrusion of igneous rock erodes the coal body, driving its structure from dense to soft and porous, resulting in a significant reduction in its physical and mechanical properties.The coal seam above the working face is easy to break under the in⁃ fluence of dynamic pressure, and the large longitudinal plastic failure depth leads to the common superposi⁃ tion of coal load, and the internal stress at a depth of 10 m above the overlying rock is at a high level.Com⁃ pared to conventional areas, the stress concentration coefficient and its influence range have significantly in⁃ creased. The combination of factors such as low coal body strength, high horizontal stress, softening of frac⁃ ture water, and extensive pre-supporting pressure led to the large-scale instability and collapse of the road⁃ way during the mining process.The research findings can serve as a reference for reasonably determining the advance support layout range for working faces under similar geological conditions.

Key words: igneous intrusion, comprehensive caving working face, advanced support pressure, coal weakened, deformation inducement