Optimization of borehole drilling and stress relief parameters for tunnel surrounding rock mass based on combination weighting and response surface methods
Chen Xiaoxiang
Ren Junlong
Abstract：Objectives With increasing mining depth,deformation of tunnel surrounding rock due to high stress has become increasingly serious.This study aims to optimize borehole stress relief parameters for the sidewalls of the Licun Coal Mine roadway.Methods Based on actual engineering geological conditions,25 experimental schemes were designed using the Box-Behnken method.Numerical simulations using FLAC3D were performed to analyze the mechanical responses under different parameter combinations.Six evaluation indicators were selected based on technical and economic considerations:construction cost,convergence of the sidewalls,roof-to-floor convergence,maximum vertical stress,plastic zone area,and construction ef-ficiency.The analytic hierarchy process(AHP)and principal component analysis(PCA)were employed to determine the weights of each evaluation indicator.Results A comprehensive evaluation model for borehole stress relief parameters was established,overcoming limitations of single evaluation criteria and subjective bias,providing a systematic and accurate evaluation methodology.A multivariate second-order regression equation was developed,using normalized comprehensive scores as the response variable and borehole stress relief parameters as independent variables.The optimized borehole stress relief parameters were found to be:borehole diameter 0.1 m,depth 4 m,and spacing 1 m×1 m,achieving the greatest overall benefit.Conclusions The proposed model provides reasonable and feasible borehole stress relief para-meters,effectively controlling surrounding rock deformation while ensuring economic efficiency,and can serve as a reference for roadway surrounding rock control design.
Keywords：borehole stress reliefresponse surface methodparameter optimizationprincipal component analysis(PCA)analytic hierarchy process(AHP)
Publication Date：2026-02-28
Online Publishing Date：2025-12-15(First online date of this platform, not the publication date of the document)
Pages：11( 60-69,142 )