Principle and technology of surrounding rock control for gob-side entry retaining in deep mine gangue backfilling face
WANG Ping,ZENG Zilong,SUN Guangjing,FENG Tao,LI Nailu,LIU Jinhai,LI Peng,JIANG Yongzhi
湖南科技大学资源环境与安全工程学院湖南科技大学煤矿安全开采技术湖南省重点实验室六盘水师范学院矿业与土木工程学院山东能源新汶矿业集团有限责任公司华北科技学院安全工程学院
深井工作面矿压显现剧烈使得沿空留巷存在诸多困难。采用矸石充填采空区可有效限制深部采场覆岩大范围的破断、运动,缓解深井工作面剧烈的矿压显现,为深井工作面沿空留巷奠定基础。通过现场实测和理论计算探讨了深井矸石充填工作面覆岩运动特征,探讨了沿空留巷围岩承载结构及其稳定性。根据新巨龙煤矿2305S-2号工作面实际情况,设计了以矸石墙+钢管混凝土立柱为主的巷旁支护结构,并提出了留巷顶板超前支护、强力护表、深部锚固,巷旁支护结构合理宽度、侧向约束、协同承载,实体煤帮卸应力、防冲击、控片帮的控制方式,留巷底板高应力深部转移的沿空留巷围岩控制原理和先固顶→再护帮→后控底的沿空留巷围岩控制原则。形成了锚杆+W钢带超前支护和长锚索+注浆锚索永久支护的沿空留巷围岩控制技术,成功实现了新巨龙煤矿2305S-2号深井矸石充填工作面沿空留巷。沿空巷道围岩实测发现留巷矸石墙变形不均匀,承载能力增长缓慢,钢管混凝土立柱钻底,顶板锚索易破断等问题。需要进一步加强留巷矸石墙的侧向约束,提高矸石墙承载能力。钢管混凝土立柱底部安装大垫板,控制立柱钻底量,沿空留巷顶板锚索要求具备一定的延伸率,实现长锚索与顶板围岩的协同变形与承载。
The intense mine pressure in the deep mine face makes it difficult to keep the gob-side entry stable. The use of gangue to fill the gob can effectively limit the large-scale breaking and movement of the overlying rock in deep stope,relieve the severe mine pressure in the deep mine face,and lay the foundation for the gob-side entry retention in the deep mine face. Through the field measurement and theoretical calculation,the movement characteristics of the overlying rock in the gangue-filled working face of the deep mine were discussed,and the bearing structure and stability of the surrounding rock of the gob-side entry retaining were discussed. According to the actual situation of the No.2305S-2 working face of Xinjulong Coal Mine,the roadside support structure was designed mainly by “gangue wall + concrete-filled steel tubular column”. It is proposed that “advanced support,strong surface protection,and deep anchoring” for the road retaining roof,“reasonable width,lateral restraint,and cooperative bearing” for the roadside support structure,“stress relief,impact resistance,and film control” for the solid coal rib,and the gob-side entry retaining surrounding rock control principle of “high stress deep transfer” of the road floor and the gob-side entry retaining surrounding rock control principle of “fixing the roof first → protecting the side → controlling the floor later”. The gob-side entry retaining surrounding rock control technology of “bolt + W steel belt” advance support and “long anchor cable + grouting anchor cable” permanent support was formed. The gob-side entry retention of No.2305S-2 deep well gangue filling working face in Xinjulong Coal Mine was successfully realized. The actual measurement of the surrounding rock of the gob-side roadway found that the deformation of the gangue wall of the roadway was uneven,the bearing capacity increased slowly,the concrete-filled steel tubular column was drilled to the bottom,and the roof anchor cable was easily broken. It is necessary to further strengthen the lateral restraint of the gangue wall and improve the bearing capacity of the gangue wall. A large plate is installed at the bottom of the CFST column to control the bottom drilling amount of the column and the roof anchor cable of the gob-side entry retention is required to have a certain elongation rate,so as to realize the coordinated deformation and bearing of the long anchor cable and the roof surrounding rock.
deep well mining;gangue filling;gob-side entry retaining;surrounding rock control;control technology
主办单位:煤炭科学研究总院有限公司 中国煤炭学会学术期刊工作委员会