基于DEM-CFD方法的基坑工程漏水漏砂引发地层运移规律的数值模拟
|
摘要
针对城市地下空间开发过程中经常出现的基坑工程漏水漏砂引发的灾害问题,利用离散元和计算流体力学耦合的方法(DEM-CFD方法)对灾害的发展过程进行数值模拟分析。在室内试验、平面双轴数值模型、渗流模型的基础上确定了土体和流体的细观参数,建立数值模型,模拟研究两类典型地层(富水砂层、富水砂层上覆黏土层)发生漏水漏砂后的地层变形规律、土体损失规律以及地应力场发展变化规律。研究结果表明,对于富水砂层,漏水漏砂后基坑外部地表形成沉降槽,地表沉降最大值与地层损失率成正相关;地下水一方面加速土体的流失,另一方面使地层发生朝向漏点的集中运动。对于富水砂层上覆黏土地层,存在使地表拉裂的临界地层损失率,且上覆黏土层越厚,临界地层损失率越大;根据漏水漏砂后的地层应力状态可将地层分为空洞区、松动区、主拉应力区以及复杂应力区。研究成果对于基坑工程漏水漏砂灾害的治理与精细化控制具有参考意义。
With the large-scale development of underground space,the hazards induced by leakage of groundwater and sand in excavations occur frequently. DEM-CFD method was adopted to simulate the process of this kind of hazard. The microscopic parameters of soil and fluid were determined based on laboratory tests,biaxial model of the particle flow code and seepage model. A numerical analysis model was developed to research the laws of ground movement,ground loss and ground stress field due to the leakage of groundwater and sand. Two typical strata including water-rich sand stratum and water-rich sand layer overlying clay stratum were considered. The results show that,for the water-rich sand stratum,the leakage of groundwater and sand induces a settlement trough on the ground surface outside the excavation,the maximum value of ground surface settlement is proportional to the soil mass loss ratio,and the leakage of groundwater accelerates the ground loss and results in the concentrated movement of ground towards the leakage point. It is also indicated that,for the water-rich sand layer overlying clay stratum,there exists a critical soil mass loss ratio leading to the crack of the ground surface,and the thicker the clay layer,the greater the critical soil mass loss ratio is. Furthermore,the ground around the leakage point could be divided into hollow area,loose area,main tensile stress area and complex stress area. The results of the research provide a reference for the hazard control and delicacy management during the leakage of groundwater and sand in excavations.
With the large-scale development of underground space,the hazards induced by leakage of groundwater and sand in excavations occur frequently. DEM-CFD method was adopted to simulate the process of this kind of hazard. The microscopic parameters of soil and fluid were determined based on laboratory tests,biaxial model of the particle flow code and seepage model. A numerical analysis model was developed to research the laws of ground movement,ground loss and ground stress field due to the leakage of groundwater and sand. Two typical strata including water-rich sand stratum and water-rich sand layer overlying clay stratum were considered. The results show that,for the water-rich sand stratum,the leakage of groundwater and sand induces a settlement trough on the ground surface outside the excavation,the maximum value of ground surface settlement is proportional to the soil mass loss ratio,and the leakage of groundwater accelerates the ground loss and results in the concentrated movement of ground towards the leakage point. It is also indicated that,for the water-rich sand layer overlying clay stratum,there exists a critical soil mass loss ratio leading to the crack of the ground surface,and the thicker the clay layer,the greater the critical soil mass loss ratio is. Furthermore,the ground around the leakage point could be divided into hollow area,loose area,main tensile stress area and complex stress area. The results of the research provide a reference for the hazard control and delicacy management during the leakage of groundwater and sand in excavations.
引文
[1]FENG S,LU S.Failure of a retaining structure in a metro station excavation in Nanchang City,China[J].Journal of Performance of Constructed Facilities,2016,30(4):1-12.
[2]TAN Y,LU Y.Forensic diagnosis of a leaking accident during excavation[J].Journal of Performance of Constructed Facilities,2017,31(5):1-15.
[3]JO Y,CHO S,JANG Y.Field investigation and analysis of ground sinking development in a metropolitan city,Seoul,Korea[J].Environmental Earth Sciences,2016,75(20):1 353.
[4]谢康和,柳崇敏,应宏伟,等.成层土中基坑开挖降水引起的地表沉降分析[J].浙江大学学报:工学版,2002,36(3):239-242.(XIEKanghe,LIU Chongmin,YING Hongwei,et al.Analysis of settlement induced by dewatering during excavation in layered soil[J].Journal of Zhejiang University:Engineering Science,2002,36(3):239-242.(in Chinese))
[5]骆祖江,刘昌军,瞿成松,等.深基坑降水疏干过程中三维渗流场数值模拟研究[J].水文地质工程地质,2005,32(5):48-53.(LUOZujiang,LIU Changjun,QU Chengsong,et al.Numerical simulation study on 3-D seepage now in deep foundation pit′s dewatering and drying[J].Hydrogeology and Engineering Geology,2005,32(5):48-53.(in Chinese))
[6]施成华,彭立敏.基坑开挖及降水引起的地表沉降预测[J].土木工程学报,2006,39(5):117-121.(SHI Chenghua,PENG Limin.Ground surface settlement caused by foundation pit excavation and dewatering[J].China Civil Engineering Journal,2006,39(5):117-121.(in Chinese))
[7]郑刚,曾超峰.基坑开挖前潜水降水引起的地下连续墙侧移研究[J].岩土工程学报,2013,35(12):2 153-2 163.(ZHENG Gang,ZENG Chaofeng.Lateral displacement of diaphragm wall by dewatering of phreatic water before excavation[J].Chinese Journal of Geotechnical Engineering,2013,35(12):2 153-2 163.(in Chinese))
[8]郑刚,曾超峰,薛秀丽.承压含水层局部降压引起土体沉降机制及参数分析[J].岩土工程学报,2014,36(5):802-817.(ZHENGGang,ZENG Chaofeng,XUE Xiuli.Settlement mechanism of soils induced by local pressure-relief of confined aquifer and parameter analysis[J].Chinese Journal of Geotechnical Engineering,2014,36(5):802-817.(in Chinese))
[9]PREENE M.Assessment of settlements caused by groundwater control[J].Geotechnical Engineering,2000,143(4):177-190.
[10]YOUSEFI M,SEDGHI-ASL M,PARVIZI M.Seepage and boiling around a sheet pile under different experimental configuration[J].Journal of Hydrologic Engineering,2016,21(12):1-9.
[11]KOLTUK S,FERNANDEZSTEEGER T M,AZZAM R.A numerical study on the seepage failure by heave in sheeted excavation pits[J].Geomechanics and Engineering,2015,9(4):513-530.
[12]郑刚,朱合华,刘新荣,等.基坑工程与地下工程安全及环境影响控制[J].土木工程学报,2016,49(6):1-24.(ZHENG Gang,ZHU Hehua,LIU Xinrong,et al.Control of safety of deep excavations and underground engineering and its impact on surrounding environment[J].China Civil Engineering Journal,2016,49(6):1-24.(in Chinese))
[13]隋旺华,蔡光桃,董青红.近松散层采煤覆岩采动裂缝水砂突涌临界水力坡度试验[J].岩石力学与工程学报,2007,26(10):2 084-2 091.(SUI Wanghua,CAI Guangtao,DONG Qinghong.Experimental research on critical percolation gradient of quicksand across overburden fissures due to coal mining near unconsolidated soil layers[J].Chinese Journal of Rock Mechanics and Engineering,2007,26(10):2 084-2 091.(in Chinese))
[14]杨伟峰,吉育兵,赵国荣,等.厚松散层薄基岩采动诱发水砂流运移特征试验[J].岩土工程学报,2012,34(4):686-692.(YANGWeifeng,JI Yubing,ZHAO Guorong,et al.Experimental study on migration characteristics of mixed water and sand flows induced by mining under thin bedrock and thick unconsolidated formations[J].Chinese Journal of Geotechnical Engineering,2012,34(4):686-692.(in Chinese))
[15]张翔,刘成禹,陈博文.近松散层突水涌砂诱发的沉降试验研究[J].水利与建筑工程学报,2017,15(6):116-121.(ZHANGXiang,LIU Chengyu,CHEN Bowen.Experimental study on settlement caused by water and sand outburst of near unconsolidated soil layers[J].Journal of Water Resources and Architectural Engineering,2017,15(6):116-121.(in Chinese))
[16]郑刚,戴轩,张晓双.地下工程漏水漏砂灾害发展过程的试验研究及数值模拟[J].岩石力学与工程学报,2014,33(12):2 458-2 471.(ZHENG Gang,DAI Xuan,ZHANG Xiaoshuang.Experimental study and numerical simulation of leaking process of sand and water of underground engineering[J].Chinese Journal of Rock Mechanics and Engineering,2014,33(12):2 458-2 471.(in Chinese))
[17]ZHENG G,DAI X,DIAO Y,et al.Experimental and simplified model study of the development of ground settlement under hazards induced by loss of groundwater and sand[J].Natural Hazards,2016,82(3):1 869-1 893.
[18]张卫杰,高玉峰,黄雨,等.水土耦合SPH数值模型的正则化修正及其应用[J].岩土工程学报,2018,40(2):262-269.(ZHANGWeijie,GAO Yufeng,HUANG Yu,et al.Normalized correction of soil-water-coupled SPH model and its application[J].Chinese Journal of Geotechnical Engineering,2018,40(2):262-269.(in Chinese))
[19]LI J,BROWN D.Upscaled Lattice boltzmann method for simulations of flows in heterogeneous porous media[J].Geofluids,2017,(4):1-12.
[20]ROHE A,LIANG D.Modelling large deformation and soil-waterstructure interaction with material point method:Briefing on MPM2017 conference[J].Journal of Hydrodynamics,2017,29(3):393-396.
[21]蒋明镜,张望城.一种考虑流体状态方程的土体CFD-DEM耦合数值方法[J].岩土工程学报,2014,36(5):793-801.(JIANG Mingjing,ZHANG Wangcheng.Coupled CFD-DEM method for soils incorporating equation of state for liquid[J].Chinese Journal of Geotechnical Engineering,2014,36(5):793-801.(in Chinese))
[22]姚志雄.三维离散元法解析砂型泥石流细观运动特征研究[J].地下空间与工程学报,2017,13(5):1 414-1 423.(YAO Zhixiong.Analysis on mesoscopic movement characteristic of sandy debris flow by 3D discrete element[J].Chinese Journal of Underground Space and Engineering,2017,13(5):1 414-1 423.(in Chinese))
[23]CLIMENT N,ARROYO M,SULLIVAN C O,et al.Sand production simulation coupling DEM with CFD[J].European Journal of Environmental and Civil Engineering,2014,18(9):983-1 008.
[24]SHIMIZU Y.Microscopic numerical model of fluid flow in granular material[J].Geotechnique,2011,61(10):887-896.
[25]CUNDALL P A,STRACK O D.A discrete numerical model for granular assemblies[J].Geotechnique,1979,29(1):47-65.
[26]ERGUN S.Fluid flow through packed columns[J].Chemical Engineering Progress,1952,48(2):89-94.
[27]秦尚林,王红亮,克高果.深井降水基坑涌水涌砂原因分析及对策[J].岩土力学,2005,26(增2):271-274.(QIN Shanglin,WANGHongliang,KE Gaoguo.Analysis of water and sand gushing out of a foundation pit and prevention contermeasures[J].Rock and Soil Mechanics,2005,26(Supp.2):271-274.(in Chinese))
[28]ZHANG Z X,HU X Y,SCOTT K D.A discrete numerical approach for modeling face stability in slurry shield tunnelling in soft soils[J].Computers and Geotechnics,2011,38(1):94-104.
[29]JIANG M,SHEN Z,ZHU F.Numerical analyses of braced excavation in granular grounds:continuum and discrete element approaches[J].Granular Matter,2013,15(2):195-208.
[30]张冬梅,高程鹏,尹振宇,等.隧道渗流侵蚀的颗粒流模拟[J].岩土力学,2017,38(增1):429-438.(ZHANG Dongmei,GAOChengpeng,YIN Zhenyu,et al.Particle flow simulation of seepage erosion around shield tunnel[J].Rock and Soil Mechanics,2017,38(Supp.1):429-438.(in Chinese))
[31]JIANG M J,KONRAD J M,LEROUEIL S.An efficient technique for generating homogeneous specimens for DEM studies[J].Computers and Geotechnics,2003,30(7):579-597.
[32]MANKOC C,JANDA A,ARéVALO R,et al.The flow rate of granular materials through an orifice[J].Granular Matter,2007,9(6):407-414.
[33]FANG Y,JU D H,HUANG W,et al.Rehabilitation of damaged soft ground tunnels[J].Journal of GeoEngineering,2006,1(1):41-49.
[34]戴轩.城市地下工程漏水漏砂灾害演化机制的试验与理论研究[博士学位论文][D].天津:天津大学,2016.(DAI Xuan.Model test and theory study on the urban underground engineering hazards induced by loss of groundwater and sand[Ph.D.Thesis][D].Tianjin:Tianjin University,2016.(in Chinese))
[2]TAN Y,LU Y.Forensic diagnosis of a leaking accident during excavation[J].Journal of Performance of Constructed Facilities,2017,31(5):1-15.
[3]JO Y,CHO S,JANG Y.Field investigation and analysis of ground sinking development in a metropolitan city,Seoul,Korea[J].Environmental Earth Sciences,2016,75(20):1 353.
[4]谢康和,柳崇敏,应宏伟,等.成层土中基坑开挖降水引起的地表沉降分析[J].浙江大学学报:工学版,2002,36(3):239-242.(XIEKanghe,LIU Chongmin,YING Hongwei,et al.Analysis of settlement induced by dewatering during excavation in layered soil[J].Journal of Zhejiang University:Engineering Science,2002,36(3):239-242.(in Chinese))
[5]骆祖江,刘昌军,瞿成松,等.深基坑降水疏干过程中三维渗流场数值模拟研究[J].水文地质工程地质,2005,32(5):48-53.(LUOZujiang,LIU Changjun,QU Chengsong,et al.Numerical simulation study on 3-D seepage now in deep foundation pit′s dewatering and drying[J].Hydrogeology and Engineering Geology,2005,32(5):48-53.(in Chinese))
[6]施成华,彭立敏.基坑开挖及降水引起的地表沉降预测[J].土木工程学报,2006,39(5):117-121.(SHI Chenghua,PENG Limin.Ground surface settlement caused by foundation pit excavation and dewatering[J].China Civil Engineering Journal,2006,39(5):117-121.(in Chinese))
[7]郑刚,曾超峰.基坑开挖前潜水降水引起的地下连续墙侧移研究[J].岩土工程学报,2013,35(12):2 153-2 163.(ZHENG Gang,ZENG Chaofeng.Lateral displacement of diaphragm wall by dewatering of phreatic water before excavation[J].Chinese Journal of Geotechnical Engineering,2013,35(12):2 153-2 163.(in Chinese))
[8]郑刚,曾超峰,薛秀丽.承压含水层局部降压引起土体沉降机制及参数分析[J].岩土工程学报,2014,36(5):802-817.(ZHENGGang,ZENG Chaofeng,XUE Xiuli.Settlement mechanism of soils induced by local pressure-relief of confined aquifer and parameter analysis[J].Chinese Journal of Geotechnical Engineering,2014,36(5):802-817.(in Chinese))
[9]PREENE M.Assessment of settlements caused by groundwater control[J].Geotechnical Engineering,2000,143(4):177-190.
[10]YOUSEFI M,SEDGHI-ASL M,PARVIZI M.Seepage and boiling around a sheet pile under different experimental configuration[J].Journal of Hydrologic Engineering,2016,21(12):1-9.
[11]KOLTUK S,FERNANDEZSTEEGER T M,AZZAM R.A numerical study on the seepage failure by heave in sheeted excavation pits[J].Geomechanics and Engineering,2015,9(4):513-530.
[12]郑刚,朱合华,刘新荣,等.基坑工程与地下工程安全及环境影响控制[J].土木工程学报,2016,49(6):1-24.(ZHENG Gang,ZHU Hehua,LIU Xinrong,et al.Control of safety of deep excavations and underground engineering and its impact on surrounding environment[J].China Civil Engineering Journal,2016,49(6):1-24.(in Chinese))
[13]隋旺华,蔡光桃,董青红.近松散层采煤覆岩采动裂缝水砂突涌临界水力坡度试验[J].岩石力学与工程学报,2007,26(10):2 084-2 091.(SUI Wanghua,CAI Guangtao,DONG Qinghong.Experimental research on critical percolation gradient of quicksand across overburden fissures due to coal mining near unconsolidated soil layers[J].Chinese Journal of Rock Mechanics and Engineering,2007,26(10):2 084-2 091.(in Chinese))
[14]杨伟峰,吉育兵,赵国荣,等.厚松散层薄基岩采动诱发水砂流运移特征试验[J].岩土工程学报,2012,34(4):686-692.(YANGWeifeng,JI Yubing,ZHAO Guorong,et al.Experimental study on migration characteristics of mixed water and sand flows induced by mining under thin bedrock and thick unconsolidated formations[J].Chinese Journal of Geotechnical Engineering,2012,34(4):686-692.(in Chinese))
[15]张翔,刘成禹,陈博文.近松散层突水涌砂诱发的沉降试验研究[J].水利与建筑工程学报,2017,15(6):116-121.(ZHANGXiang,LIU Chengyu,CHEN Bowen.Experimental study on settlement caused by water and sand outburst of near unconsolidated soil layers[J].Journal of Water Resources and Architectural Engineering,2017,15(6):116-121.(in Chinese))
[16]郑刚,戴轩,张晓双.地下工程漏水漏砂灾害发展过程的试验研究及数值模拟[J].岩石力学与工程学报,2014,33(12):2 458-2 471.(ZHENG Gang,DAI Xuan,ZHANG Xiaoshuang.Experimental study and numerical simulation of leaking process of sand and water of underground engineering[J].Chinese Journal of Rock Mechanics and Engineering,2014,33(12):2 458-2 471.(in Chinese))
[17]ZHENG G,DAI X,DIAO Y,et al.Experimental and simplified model study of the development of ground settlement under hazards induced by loss of groundwater and sand[J].Natural Hazards,2016,82(3):1 869-1 893.
[18]张卫杰,高玉峰,黄雨,等.水土耦合SPH数值模型的正则化修正及其应用[J].岩土工程学报,2018,40(2):262-269.(ZHANGWeijie,GAO Yufeng,HUANG Yu,et al.Normalized correction of soil-water-coupled SPH model and its application[J].Chinese Journal of Geotechnical Engineering,2018,40(2):262-269.(in Chinese))
[19]LI J,BROWN D.Upscaled Lattice boltzmann method for simulations of flows in heterogeneous porous media[J].Geofluids,2017,(4):1-12.
[20]ROHE A,LIANG D.Modelling large deformation and soil-waterstructure interaction with material point method:Briefing on MPM2017 conference[J].Journal of Hydrodynamics,2017,29(3):393-396.
[21]蒋明镜,张望城.一种考虑流体状态方程的土体CFD-DEM耦合数值方法[J].岩土工程学报,2014,36(5):793-801.(JIANG Mingjing,ZHANG Wangcheng.Coupled CFD-DEM method for soils incorporating equation of state for liquid[J].Chinese Journal of Geotechnical Engineering,2014,36(5):793-801.(in Chinese))
[22]姚志雄.三维离散元法解析砂型泥石流细观运动特征研究[J].地下空间与工程学报,2017,13(5):1 414-1 423.(YAO Zhixiong.Analysis on mesoscopic movement characteristic of sandy debris flow by 3D discrete element[J].Chinese Journal of Underground Space and Engineering,2017,13(5):1 414-1 423.(in Chinese))
[23]CLIMENT N,ARROYO M,SULLIVAN C O,et al.Sand production simulation coupling DEM with CFD[J].European Journal of Environmental and Civil Engineering,2014,18(9):983-1 008.
[24]SHIMIZU Y.Microscopic numerical model of fluid flow in granular material[J].Geotechnique,2011,61(10):887-896.
[25]CUNDALL P A,STRACK O D.A discrete numerical model for granular assemblies[J].Geotechnique,1979,29(1):47-65.
[26]ERGUN S.Fluid flow through packed columns[J].Chemical Engineering Progress,1952,48(2):89-94.
[27]秦尚林,王红亮,克高果.深井降水基坑涌水涌砂原因分析及对策[J].岩土力学,2005,26(增2):271-274.(QIN Shanglin,WANGHongliang,KE Gaoguo.Analysis of water and sand gushing out of a foundation pit and prevention contermeasures[J].Rock and Soil Mechanics,2005,26(Supp.2):271-274.(in Chinese))
[28]ZHANG Z X,HU X Y,SCOTT K D.A discrete numerical approach for modeling face stability in slurry shield tunnelling in soft soils[J].Computers and Geotechnics,2011,38(1):94-104.
[29]JIANG M,SHEN Z,ZHU F.Numerical analyses of braced excavation in granular grounds:continuum and discrete element approaches[J].Granular Matter,2013,15(2):195-208.
[30]张冬梅,高程鹏,尹振宇,等.隧道渗流侵蚀的颗粒流模拟[J].岩土力学,2017,38(增1):429-438.(ZHANG Dongmei,GAOChengpeng,YIN Zhenyu,et al.Particle flow simulation of seepage erosion around shield tunnel[J].Rock and Soil Mechanics,2017,38(Supp.1):429-438.(in Chinese))
[31]JIANG M J,KONRAD J M,LEROUEIL S.An efficient technique for generating homogeneous specimens for DEM studies[J].Computers and Geotechnics,2003,30(7):579-597.
[32]MANKOC C,JANDA A,ARéVALO R,et al.The flow rate of granular materials through an orifice[J].Granular Matter,2007,9(6):407-414.
[33]FANG Y,JU D H,HUANG W,et al.Rehabilitation of damaged soft ground tunnels[J].Journal of GeoEngineering,2006,1(1):41-49.
[34]戴轩.城市地下工程漏水漏砂灾害演化机制的试验与理论研究[博士学位论文][D].天津:天津大学,2016.(DAI Xuan.Model test and theory study on the urban underground engineering hazards induced by loss of groundwater and sand[Ph.D.Thesis][D].Tianjin:Tianjin University,2016.(in Chinese))
© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |