摘要
为了解决软岩采场终采线附近大巷受工作面回采应力长时高压作用引起的巷道围岩结构大变形问题,以风水沟煤矿软岩地质条件为工程背景,从力源传递角度出发,提出了顶板深部围岩双主动超前深孔预裂爆破卸压原理,建立了爆破裂隙带构造应力场力学模型和终采线附近高位稳定岩层弹性基础连续板力学模型,对比分析了采场超前支承压力和爆破裂隙带构造应力分布特征,研究了顶板深部围岩双主动超前爆破卸压机制。研究得出:风水沟煤矿软岩采场超前支承压力动态演化规律具有动压影响区域广,峰值影响范围大,应力集中程度高的特点;终采线区域顶板深部围岩双主动超前爆破卸压后,爆破裂隙带构造应力场剧烈影响范围减小,应力集中程度降低,顶板下沉量和弯矩明显减小,工作面终采线预裂岩层及时垮落,冒落岩体的碎胀效应有效控制高位稳定岩层的变形以及破坏发展模式;煤柱区爆破裂隙带切断应力传递路径,采场应力环境得到明显优化。在工作面回采结束3个月后,现场监测的大巷围岩垂直应力增量在5%以下,巷道顶底板及两帮的移近量较小。研究结果表明,顶板双主动爆破卸压后形成的裂隙带阻挡了超前支承压力向前传递,降低了巷道围岩应力,减小了大巷变形。
In order to solve the problem of large deformation of roadway’s surrounding rock structure caused by the long-term and high-pressure action of mining stress in the main entry near the stop line of soft rock working face,taking the soft rock geological conditions of Fengshuigou mine as the engineering background,the principle of pre-splitting roof by dual active advanced blasting pressure relief for deep surrounding rock in the roof was proposed from the perspective of force transmission.The mechanical model of tectonic stress field in the blast fracture zone and the mechanical model of the elastic foundation continuous plate near the stop line was established,and the advancing abutment pressure distribution characteristics was compared to the structural stress distribution characteristics of the blast fracture zone.The pressure-relief mechanism of dual active advanced blasting in deep surrounding rock of roof was studied.The paper concludes that the dynamic evolution law of the advancing abutment pressure of soft rock stope in Fengshuigou mine is characterized by a wide range of dynamic pressure influence,a large range of peak value influence and a high degree of stress concentration.After the pressure-relief by the dual active advanced blasting in the deep surrounding rock of roof,the scope of influence on the blasting fracture zone’s structural stress field is reduced dramatically,and the degree of stress concentration is also reduced.The pre-splitting roof collapses in time near the stop line of soft rock working face,which can effectively control the deformation and failure development mode of high stable rock by falling rock mass.The blasting fracture zone in the coal pillar area cuts off the stress transfer path,which can obviously optimize the stress environment of the working face.The vertical stress increment of the surrounding rock monitored on site is less than 5%,and the deformations of the roof and floor and two sides of the roadway are small in three months after the end of working face mining.The results show that the blasting fracture zone weakens the advancing abutment pressure forward transmission,which reduces the stress and the deformation of the surrounding rock of the roadway.It provides a reference for large deformation control of surrounding rock in soft rock roadway with similar conditions.
作者
高晓进
李煜炜
张振金
张震
于海涛
黄志增
岳春辉
GAO Xiaojin;LI Yuwei;ZHANG Zhenjin;ZHANG Zhen;YU Haitao;HUANG Zhizeng;YUE Chunhui(Coal Mining&Designing Department,Tiandi Science&Technology Co.,Ltd.,Beijing 100013,China;Mining Institute,China Coal Research Institute,Beijing 100013,China;CCTEG Coal Mining Research Institute,Beijing 100013,China;Inner Mongolia Pingzhuang Energy Co.,Ltd.,Chifeng 024076,China;Inner Mongolia Yitai Group Co.,Ltd.,Ordos 017000,China)
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2020年第S02期589-598,共10页
Journal of China Coal Society
基金
中国煤炭科工集团有限公司科技创新创业资金专项面上资助项目(2018MS020)
天地科技股份有限公司开采设计事业部科技创新基金面上资助项目(KJ-2018-TDKCZL-07)
天地科技股份有限公司科技创新创业资金专项资助项目(2018-TD-MS022)
关键词
软岩采场
超前支承压力
超前卸压
爆破裂隙
构造应力
soft rock working face
advancing abutment pressure
pressure-relief by dual active advanced blasting
blasting fracture zone
structural stress field
作者简介
高晓进(1989—),男,河北石家庄人,硕士。E-mail:mkzygxj@163.com
