摘要
针对软弱煤岩体锚固性能差、锚固力低的技术难题,提出锚固孔孔底扩孔锚固提高锚固力的方法,并对扩孔锚固锚杆荷载传递过程和钻孔围岩应力分布特征等进行理论分析、实验室试验和数值模拟研究。研究结果表明:扩孔锚固增强了锚固体与钻孔围岩的相互作用,提高了锚杆锚固力,在拉拔荷载作用下扩孔锚固所能提供的锚固力显著高于正常锚固,锚固失效后扩孔段钻孔围岩经历"压密-破坏-再压密"循环变化过程,锚固力衰减较缓慢,且保持较高水平的残余锚固力;在动压荷载作用下,扩孔锚固状态下锚固力衰减少,具有较好的抵抗动压扰动破坏的特性,对解决动压软弱煤岩体巷道锚杆支护具有重要指导意义。
In view of the technical problems of poor and low anchorage performance of bolt in soft coal and rock mass, the method of reaming anchor at the bottom of the hole has been put forward to improve anchoring force. The load transfer process of enlarged anchor bolt and the stress distribution characteristics of borehole surrounding rock have been analyzed through theoretical analysis, laboratory tests and numerical simulation. It is concluded that the interaction between anchor and borehole surrounding rock has been enhanced, and the anchoring force of bolt has been increased. Anchorage force coming from reaming anchor under the condition of pull-out resistance is significantly higher than that of normal anchorage. After anchorage invalidation, the surrounding rock of borehole in reaming section undergoes a cyclic process of compaction-destruction-re-compaction,and the anchoring force of reaming anchorage is attenuating slowly, and a higher level of residual anchoring force is kept. Under the dynamic pressure load, anchorage force is attenuating slowly with the condition of reaming anchor age, and it has better resistance to dynamic pressure disturbance, which has important guiding significance to solving the problem of dynamic pressure soft coal and rock roadway bolt support.
作者
程利兴
张辉
姜鹏飞
蔡瑞春
李冰冰
CHENG Lixing;ZHANG Hui;JIANG Pengfei;CAI Ruichun;LI Bingbing(School of Resource and Safety Engineering,China University of Mining&Technology(Beijing),Beijing 100083,China;Coal Mining and Designing Department,Tiandi Science and Technology Co Ltd,Beijing 100013,China;School of Energy Science and Engineering,Henan Polytechnic University,Jiaozuo,Henan 454000,China;Xinji Energy Co Ltd,China Coal Group Corp,Fuyang,Anhui 232170,China)
出处
《采矿与安全工程学报》
EI
CSCD
北大核心
2019年第6期1153-1160,共8页
Journal of Mining & Safety Engineering
基金
国家重点研发计划项目(2017YFC0603003)
国家自然科学基金项目(51704160)
河南省科技厅科技攻关项目(162102210224)
河南省教育厅科技攻关项目(15B440002)
关键词
软弱煤岩体
扩孔锚固
锚杆拉拔
衰减特性
动压响应
soft coal and rock mass
reaming anchor
pull-out test
attenuation characteristics
dynamic load response
作者简介
程利兴(1987-),男,河南省永城市人,博士研究生,主要从事巷道围岩控制方面的研究。E-mail:chenglixinghpu@163.com,Tel:18300600669。
