工矿自动化2025，Vol.51Issue(1)：145-155,11.DOI:10.13272/j.issn.1671-251x.2024090024
大柳塔煤矿沿空留巷柔模砼墙支护阻力核定及失稳判据研究
Study on the determination of support resistance and instability criteria for flexible concrete wall support in gob-side entry retaining at Daliuta Coal Mine
摘要
Abstract
The stability of the gob-side entry retaining with flexible concrete walls and the collapse structure of the overburden above the working face are key factors that determine the success of entry retaining.Taking the 52606 working face at Daliuta Coal Mine as the research object,a similar material simulation experiment was conducted.The results showed that after mining the 52605 and 52606 working faces,the overburden above the concrete wall collapsed into a short cantilever beam structure.The side collapse angle of the concrete wall was greater than that of the coal wall.After secondary mining,fractures developed from the two working faces,connecting to the surface,and slight ground subsidence appeared above the concrete wall.Based on the analysis of the overburden collapse structure characteristics,it was determined that the first fracture of the roof in the gob-side entry occurred on the side of the backfill material above the gob area,while the second fracture occurred in the rock layer forming the cantilever beam structure near the coal wall.Combining theoretical analysis,the stress distribution characteristics of the flexible concrete walls in the gob-side entry were obtained.According to whether the portal support was removed during different stages of gob-side entry usage,it was proposed that the support resistance of the concrete wall during the retaining phase should be calculated using the separated rock block method,while the support resistance during the reuse phase should be calculated using the inclined rock beam method.The stability of the flexible concrete wall was found to be related to its safety factor.During the mining process,as long as the safety factor remained greater than 1,the concrete wall would not experience instability or failure.Verification results showed that when portal support was used as temporary support during the retaining phase,to ensure the safety factor of the concrete wall was greater than 2,its strength had to exceed 5.4 MPa.After the portal support was removed,the fractured rock blocks and overburden load were borne by the concrete wall.Additionally,dynamic loads caused by mining continued to affect the concrete wall.However,the safety factor of the concrete wall was 3.9,indicating that the wall remained relatively stable.Although the stress on the concrete wall changed continuously,the changes were not significant,and no sharp increases or decreases in stress were observed.This suggests that the concrete wall could effectively support the roof,maintaining stability throughout.关键词
沿空留巷/柔模砼墙/砼墙安全系数/门式支架/采动阶段/覆岩运移规律/支护阻力Key words
gob-side entry retaining/flexible concrete wall/concrete wall safety factor/portal support/mining stage/overburden movement pattern/support resistance分类
矿山工程引用本文复制引用
李刚,刘航,迟国铭,石占山,范永君..大柳塔煤矿沿空留巷柔模砼墙支护阻力核定及失稳判据研究[J].工矿自动化,2025,51(1):145-155,11.基金项目
国家自然科学基金资助项目(52174077,5200418). （52174077,5200418）
