沿空留巷直接顶稳定性突变分析及其控制

保持直接顶稳定,降低其突变所引起的危害是沿空留巷顶板控制的关键。基于沿空留巷直接顶力学模型,采用能量平衡分析法,建立直接顶突变的燕尾突变模型。结合某工程实例,阐述沿空留巷直接顶稳定性突变机理,分析巷帮煤体支撑力、巷内支护阻力、充填体支撑力对直接顶稳定性突变的影响。实践表明,增加工作面超前加固范围,巷内支护采用高预应力强力锚杆与锚索等主动支护,巷旁采用膏体充填,能够提高充填体早期强度,延缓直接顶稳定性突变的发生和减轻突变发生的烈度。

Analysis and Control of Stability Mutation of Immediate Roof in the Gob-side Entry Retaining

It is the key to controlling immediate roof of the gob-side entry retaining that maintaining the stability of immediate roof and reducing the harm arising from mutation.Based upon mechanical model of immediate roof,energy balance analysis method was applied to establish a swallowtail catastrophe model.Based on a certain engineering example,the mutation mechanism of immediate roof was illustrated,and the impacts of support force of coal,roadway-in support resistance and backfill support force on the stability mutation of immediate roof were analyzed.Practice shows that to expand advance reinforcement scope of working face,to use roadway-in initiative supporting of high strength prestressed anchor bolts and roadside paste backfill,and to improve early strength of roadside backfill can delay stability mutation of immediate roof and reduce the intensity of mutation.