Zoned support technology for concrete filling in gob-side entry retaining

SONG Guanlin; LIANG Wenxu

doi:10.11799/ce202601011

Abstract：To address the surrounding rock control in gob-side entry retaining with concrete roadside filling,laboratory tests were conducted to determine the uniaxial compressive strength of concrete filling under different curing ages,relationship between concrete strength and curing age,as well as the concrete peak compressive strength were obtained.Borehole imaging was used to determine the extent of surrounding rock loosening and failure at different locations along the roadway,based on which the minimum lengths of roof anchor cables and sidewall bolts for the retained entry were determined as not less than 4.90 m and 3.70 m,respectively.Numerical simulation was employed to identify the advance influence range of the working face and the degree of disturbance on the surrounding rock at different positions,establishing that the reasonable distance for advance reinforced support should be not less than 19.08 m.Based on these findings,a zoned asymmetric control technology for surrounding rock in concrete roadside filling gob-side entry retaining was proposed.The feasibility of this zoned asymmetric control technology was analyzed through indicators such as internal surrounding rock pressure within the filling,roof separation,and surrounding rock convergence,verifying the rationality of the research results.