摘要
在煤矿开采过程中,受复杂水文地质条件的影响,工程建设经常会遭遇突涌水、塌方等地质灾害,严重制约了地下工程的安全建设和发展。注浆技术作为地下突涌水灾害治理的有效手段,在煤矿水害防治领域得到了广泛应用。为研究动水条件下倾斜裂隙注浆扩散规律及封堵机理,通过自主研发的动水注浆试验系统,进行了倾斜裂隙动水注浆试验;采用有限元法求解Navier-Stokes方程和浆水相界面控制方程,获得了注浆过程中不同时刻的浆液扩散形态和扩散面积,分析了倾斜裂隙空间内的流速场和压力场分布规律,并与试验结果进行了对比验证;基于模型试验与数值模拟结果,揭示了堵水关键域浆液运移规律,建立了倾斜裂隙动水注浆堵水关键域扩散模型。结果表明:当注浆压力恒定不变时,随着裂隙倾角和动水流量的增大,浆液沿顺水方向扩散距离均随之迅速增大至出流边界,沿逆水方向和垂直于动水流向的扩散距离明显减小,导致浆液扩散面积不断减小,使得浆液扩散形态由圆形变为椭圆形,最终到达出流边界时呈U形;在注浆扩散过程中,随着裂隙倾角的增加,浆液不断驱替过水断面逐步形成了高流速过水通道,使得裂隙横断面流速分布呈现出岭陡谷宽的形状;同时,在倾斜裂隙不同高差位置压力曲线随时间同步变化,沿顺、逆水方向(测线1)压力分布从动水入口至出流边界呈递减趋势,且裂隙倾角越大,压力场衰减越快,沿垂直于水流方向(测线3)压力分布具有对称性,表现为在注浆孔处压力值最大,且注浆孔周围压力衰减速度最快,随着与注浆孔距离的增加,压力衰减速度逐渐减小并趋于平缓。根据浆液在裂隙中的分区-分层扩散方式,确定了堵水关键域位置与范围大小,且堵水关键域面积的试验测试结果与理论计算值之间的误差均小于8.5%,表明本文所建立扩散模型能够描述堵水
In the process of coal mining,due to the influence of complex hydrogeological conditions,the engineer⁃ing construction often encounters some geological disasters such as water inrush and collapse,which seriously restricts the safe construction and development of underground mines.As an effective means of underground water in⁃rush disaster management,the grouting technology has been widely used in the field of coal mine water disaster preven⁃tion and control.To study the diffusion law and plugging mechanism of inclined fracture grouting under dynamic wa⁃ter condition,a dynamic water grouting test for inclined fracture was carried out by the self⁃developed dynamic wa⁃ter grouting test system.The Navier⁃Stokes equations and the governing equations of slurry⁃water interface were solved by finite element method,the grout diffusion shape and diffusion area at different moments during the grouting process were obtained,the distribution law of velocity field and pressure field in inclined fracture space was analyzed,and the results were compared with the experimental results.Based on the model test and numerical simulation results,the mi⁃gration law of slurry in the key area of water plugging was revealed,and the key area diffusion model of water plugging by dynamic water grouting in inclined fracture was established.The results show that when the grouting pressure is constant,with the increase of fracture dip angle and dynamic water flow,the diffusion distance of slurry along the downwater direction increases rapidly to the outflow boundary.The diffusion distance of the slurry along the direction against the water and perpendicular to the flow direction decreases obviously.As a result,the diffu⁃sion area of the slurry decreases continuously,and the diffusion form of the slurry changes from round to oval,and fi⁃nally reaches the outflow boundary in a U shape.In the process of grouting diffusion,with the increase of the dip angle of the fracture,the slurry continuously displaces the water through sec
作者
张嘉凡
孙晓东
刘洋
覃祥瑞
张慧梅
ZHANG Jiafan;SUN Xiaodong;LIU Yang;QIN Xiangrui;ZHANG Huimei(Department of Mechanics,Xi’an University of Science and Technology,Xi’an 710054,China;China Coal Technology&Engineering Xi’an Research Institute(Group)Co.,Ltd.,Xi’an 710054,China;School of Architecture and Civil Engineering,Xi’an University of Science and Technology,Xi’an 710054,China)
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2023年第S02期575-588,共14页
Journal of China Coal Society
基金
国家自然科学基金资助项目(12172280)
陕西省自然科学基金重点资助项目(2020JZ-53)。
关键词
倾斜裂隙
动水注浆
堵水关键域
扩散模型
inclined fissures
dynamic water grouting
key areas of water plugging
diffusion model
