摘要
针对山西古交矿区穿越松散富水围岩斜井工程,基于工程地质勘探情况,对主要含水层分阶段进行数值模拟分析,结果显示进入砂卵石层后工作面出现负孔隙水压力,至中砂岩层工作面出现较大张拉-剪切破坏,且破坏范围随掘进深度不断扩大.据此确定表土层采用壁后注浆和地面预注浆综合防治涌水,井壁结构为钢筋混凝土砌碹,而表土和基岩交界段则采用工作面预注浆超前加固,钢筋网喷棚架初次支护和混凝土二次衬砌的支护方式.为评价支护效果,采用钻芯取样对浆液固结体作抗压强度测试和声波检测评价注浆效果,对井筒典型断面收敛变形、支护结构受力及地表建筑物沉降进行实时监测,结果表明:断面两帮和顶底最大收敛量约75mm和55mm,钢筋应力远小于屈服强度,地面沉降量控制在15mm,井壁结构受力合理且有较高的安全储备,保证了斜井的围岩稳定.
For the fact that Gujiao Mining Area in Shanxi province passes through a project of a loose and water-rich surrounding rock for mine inclined shaft,based on conditions of engineering geological exploration,the main aquifers were phrased to conduct numerical simulation analysis.Research findings show that negative pore water pressure happens after working face enter sandy gravel layers,while when reaching medium sandstone layers,working face is of a larger sheartension failure.And failure zone increases along with excavation depth.Grouting behind shaft and surface ground pre-grouting are adopted in topsoil layer to control water burst,and shaft lining structure is reinforced concrete brickwork.On the other hand,on the interface between topsoil and bedrock is a support pattern of working face pre-grouting advance reinforcement,primary support of steel mesh spray shed frame and the second support of concrete lining.To evaluate support effect,drilled core sampling is used to perform compressive strength test and acoustic detection of slurry concretion.And real time monitoring is conducted as to convergence deformation,the stress state of support structure of shaft typical section and surface buildings settlement observation.Accordingly,results show that the largest convergence of two sides and roof to floor are about 75 mm and 55 mm respectively,that reinforcement stress remains far less than yield strength,that land subsidence is controlled at 15 mm,and that shaft lining structure under stress is reasonable and has a high safety reserve,ensuring surrounding rock stability of the inclined shaft.
作者
姚韦靖
庞建勇
YAO Weijing;PANG Jianyong(School of Civil Engineering and Architecture,Anhui University of Science and Technology,Huainan 232001,China)
出处
《应用基础与工程科学学报》
EI
CSCD
北大核心
2020年第2期422-434,共13页
Journal of Basic Science and Engineering
基金
安徽省高校自然科学重大项目(KJ2015ZD20)
安徽理工大学校级资助项目(QN2019115)
关键词
斜井井筒
松散富水围岩
数值模拟
注浆技术
井壁结构
现场监测
inclined shaft
loose and water-rich surrounding rock
numerical simulation
grouting technology
shaft lining
field monitoring
