Roadway layout optimization method and its application under three-dimensional stress based on PSO-AHP algorithm

Under three-dimensional high stress conditions, optimizing the orientation of a roadway relative to the principal stress directions can reduce the impact of high stress on the stability of the surrounding rock. Using theoretical analysis and field tests, a coupled optimization algorithm based on particle swarm optimization and analytic hierarchy process (PSO-AHP) was proposed to determine the optimal roadway layout parameters. This approach was applied to the transportation roadway of the 1104 working face at the Weijiadi coal mine. The results show that the dip angle α and azimuth angle β significantly influence the distribution of the deviatoric stress in the surrounding rock. The sensitivity of surrounding rock to changes in α and β varies under different stress fields. Adjusting the more sensitive parameters reduces deviatoric stress and enhances the stability of the roadway. The PSO-AHP optimization algorithm uses deviatoric stress as an evaluation index, first calculating the optimal layout parameters for different sections of the roadway and then determining the overall optimal parameters through an evaluation matrix and function. In the 1104 working face of Weijiadi coal mine, the roadway layout based on the optimal parameters derived from the PSO-AHP algorithm reduced the average deviatoric stress at various depths of the surrounding rock, with all reduction coefficients below 1. Additionally, the location of the maximum deviatoric stress shifted. Compared to the original layout scheme, the optimized layout improved stress distribution and overall stability. The study also proposed an asymmetric support system, which demonstrated excellent field performance.