摘要
针对高应力软岩巷道的大量变形与破坏问题,以江西曲江煤矿-850 m水平运输大巷为例,研究了变形机理和返修控制技术。首先,对该大巷的变形及破坏情况选取7个具有代表性的地段进行现场调查,发现变形与破坏形式主要包括两帮内挤、侧墙张裂、U型钢棚架弯曲或折断、底板鼓起和顶板垮落等;进行了X衍射实验和围岩内部变形结构的现场窥视,表明该巷道围岩含泥质矿物较多,松动圈较大(4 m左右)。然后,采用巴顿分类Q值、地质力学RMR值和松动圈估计值等将-850 m水平运输大巷的各调查段巷道稳定性归为Ⅴ,Ⅳ和Ⅲ类,相应地将这3类巷道称为垮冒巷道、特殊巷道和标准巷道,并给出了初步支护方案。最后,借助于工程类比、围岩分类、截面面积校核和提出的锚固段长度经验公式等方法得到了返修巷道锚索(锚杆)的长度、间排距、强度、直径和锚固段长度等主要参数。由此,-850 m水平运输大巷试验段巷道选取了"锚杆、金属网、喷浆、锚索、注浆和底板锚索"的综合支护方式。应用表明:经过147 d,巷道两帮收敛量最大值仅为66 mm,顶底板移近量最大值仅为119 mm,监测后期的收敛速率均小于1 mm/d,处于稳定状态。
Aiming at many problems about deformation and failure of high stress and soft rock roadway, the -850 m main haulage way of Qujiang Mine was taken as an example to study the deformation mechanism and rework control technology. Firstly, deformation and failure situations of seven typical sections in the roadway were surveyed, it is found that main deformation and failure forms include two sides＇ extrusion, side wall tensional fracture, U section steel dis- tortion, floor heave and roof caving. Results of X diffraction experiment and internal failure detection test show that sur- rounding rock contains many argillaceous mineral and formed larger loose circles （ about 4 m）. And then, Barton Clas- sification Q value, Geological Mechanics RMR value and Loose Circle value were used to classify stability of all sur- veyed roadway sections including V, IV and III class. These three class roadway classified accordingly into collapsedroadway, special roadway and standard roadway, and put forward respectively preliminary supporting projects. Lastly, engineering analogy, rock classification, section area checking and anchorage length calculation were adapted to ana- lyze anchor or cable length of rework roadway, row ＆ line space, strength, diameter and anchorage length. Therefore, the comprehensive support method with ＂bolt＋metal net＋gunite covering＋anchor＋grouting＋floor anchor＂ was selected to rework -850 m main haulage way. The application shows that sides convergences of roadway no more than 66 mm after 147 days,roof and floor convergences less than 119 mm and late convergence rates less than 1 mm/d.
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2014年第4期614-623,共10页
Journal of China Coal Society
基金
国家自然科学基金资助项目(51104063
51374105)
湖南省教育厅资助项目(12cy013)
关键词
高应力
软岩巷道
变形机理
返修
支护设计
high stress
soft rock roadway
deformation mechanism
rework
support design
作者简介
余伟健（1978-），男，江西都昌人，副教授。E—mail：ywjlah@163．com
