摘要
为了解决煤矿大断面托顶煤回采巷道支护问题,以王庄煤矿7105工作面运输巷为工程背景,通过数值模拟分析了大断面托顶煤巷道裸巷平衡时围岩塑性区形态、位移及应力演化规律;基于普氏自然平衡拱理论,建立了两帮稳定时大断面托顶煤巷道顶板冒落拱力学模型,通过数学计算得到了分层冒落拱高度,运用两帮塑性区力学模型计算托顶煤巷道帮部塑性区宽度,结合数值模拟方法,设计了锚杆锚索联合支护参数和支护方案,并应用于工程实践。研究结果表明:巷道周边出现"蛙形"塑性区,顶板拉伸破坏区呈规则穹隆形,与巷道顶板普氏拱效应相吻合,托顶煤离层严重,冒落拱高度超过托顶煤厚度;两帮在该工况下塑性区发展有限,帮部较为稳定;在厚顶煤存在情况下,大断面托顶煤巷道变形特点是顶板最大,帮部次之,底板最小。现场监测结果证明,借助大断面托顶煤巷道顶板冒落拱力学模型、两帮塑性区力学模型理论计算,结合数值模拟比选的巷道锚杆支护参数和支护方案,能有效控制围岩变形,保持巷道稳定。
In order to solve the support problem of large section gateway with top coal in coal mine,the 7105 working face haulage gateway in Wangzhuang coal mine was taken as engineering example,large section top-coal roadway plastic zone form,displacement and stress evolution law of surrounding rock when naked entry equilibrated conditions were analyzed by using numerical simulation.Based on platts' natural equilibrium arch theory,the top-coal roof of large section roadway with stable coal-walls caving arch mechanical model was established,and layered caving arch height was obtained by mathematical calculation,using the roadway sides plastic zone mechanical model was used to work out the plastic zone width of the top-coal roadway sides.And combined with numerical simulation method,the rock bolt,cable combined support reasonable supporting parameters and support schemes were designed and applied to practical engineering.The results showed that a plastic zone looks like "frog"formed in surrounding rock,the regularly dome-shaped tensile failure zone was in conformity with the platts' arch effect of roadway roof and the top-coal serious bed separation leading to the caving arch height larger than top-coal thickness;Under such conditions,two sides plastic zone was smaller and the sides were relatively stable;As the thick top coal exists,the deformation characteristic of large section top-coal roadway was roof as the biggest,followed by sides and floor.Field monitoring results proved that topcoal roof of large section roadway with stable coal-walls caving arch mechanical model and roadway sides plastic zone mechanical model,combined with numerical simulation comparison the roadway bolt supporting parameters and support schemes determined,can effectively control the deformation of surrounding rock and keep the stability of roadway.
出处
《矿业科学学报》
2017年第5期439-448,共10页
Journal of Mining Science and Technology
基金
国家自然科学基金面上资助项目(51474218
51134025)
关键词
煤矿
大断面
托顶煤巷道
离层
分层拱
塑性区
支护参数
coal mine
large section
gateway with top coal
bed separation
layered caving arch
plastic zone
supporting parameters
