Influencing factors analysis of deformation and failure of coal seam roadway based on plastic zone expansion

Abstract

In order to analyze the influence of coal seam roadway occurrence conditions on the deformation and destruction of roadway surrounding rock, the coal seam thickness, roof and floor thickness, roof and floor lithology, and coal seam gas pressure are selected as the analysis factors, and the orthogonal test is carried out using FLAC3D numerical simulation software to obtain the plastic zone of coal seam roadway surrounding rock under different occurrence conditions, and the influence degree of each factor on the expansion of plastic zone is analyzed. The research shows that the factors affecting the deformation and damage degree of surrounding rock of coal seam roadway are in order of coal seam thickness, coal seam gas pressure, floor thickness, floor lithology, roof thickness and roof lithology from high to low. Among them, the thickness of coal seam and coal seam gas pressure have a significant impact on the deformation and damage of surrounding rock and are positively correlated. When the roof thickness is 30 m, the coal seam thickness is 15 m, the floor thickness is 15 m, the roof lithology is mudstone, the floor lithology is siltstone, and the coal seam gas pressure is 0.7 MPa, the maximum radius of the surrounding rock plastic zone of the coal seam roadway is the largest, and the roadway is most prone to deformation and damage.

Keywords

• coal seam roadway
• influencing factors
• plastic zone
• orthogonal test
• deformation and failure of surrounding rock