Research on optimization method for excavation sequence of deep chamber groups

ZANG Jincheng; LI Donghao; ZHANG Lu; SUN Lingfeng; HUANG Yubing

doi:10.16186/j.cnki.1673-9787.2023100063

Abstract：Objectives To reduce the mutual disturbances caused by the excavation of deep chamber groups.Methods This study uses Wanfu Coal Mine,a mine under construction in a region with extremely thick al-luvial layers,as the engineering background.Quantitative evaluation indicators,such as surrounding rock deformation and excavation-induced mutual disturbance degree,were established.Based on the overall opti-mization principle of minimizing the total deformation of the chamber group as the primary objective and minimizing the mutual disturbance between excavations as the secondary objective,a method for evaluating and optimizing the excavation sequence of deep chamber groups was proposed.Numerical simulations were conducted to investigate the excavation of individual chambers and various excavation sequences for the chamber groups.Results The surrounding rock deformation at the belt conveyor head chamber reached 416.2 mm,while the main shaft contact roadway exhibited a deformation of only 58.6 mm.Scheme 3 dem-onstrated the lowest total excavation disturbance degree(286.38),which was 37.22%lower than that of Scheme 5(456.20).Using the proposed evaluation and optimization method,Scheme 3 was identified as the optimal excavation scheme,with the smallest overall deformation of surrounding rock and the least exca-vation disturbance.The weighted total score of Scheme 3 was 11,and the cumulative deformation incre-ment of all chambers was 178 mm,representing a 30.26%reduction in excavation interference compared to the least optimal scheme.The scientific validity of the proposed method was verified.Conclusions The study revealed the non-uniformity of chamber deformation and clarified that larger chamber cross-sectional dimensions lead to more pronounced unloading of surrounding rock and greater stress release.The evalua-tion and optimization method successfully identified the optimal excavation sequence for the deep chamber groups in Wanfu Coal Mine.