人工冻结粉质黏土力学性能演化规律研究
|
摘要
基于地铁工程中人工地层冻结法应用的工程背景,以粉质黏土地层为研究对象,通过室内试验研究冷冻温度、含水量和围压等因素对人工冻结粉质黏土强度和冻胀变形演化规律的影响。结果表明:冷冻温度、含水量和围压显著影响人工冻结粉质黏土的应力应变发展趋势和破坏模式,三轴剪切强度、弹性模量与冷冻温度、含水量和围压的相关性因三者的耦合作用而呈现不同的演化趋势;单向冻结模式下,温度场达到恒定温度梯度后,人工冻结粉质黏土达到了最大冻胀变形量;冻胀率与冷冻温度之间存在较好的线性回归关系,且外界水源补给条件下粉质黏土冻胀率远大于封闭不补水条件;冷冻温度、含水量和地层埋深是确保人工地层冻结技术中冻结壁达到设计强度、控制地表变形以及防止结构物破裂、渗水或漏泥等问题的3个关键指标。
Motivated by the application and development of artificial freezing method in subway engineering,with the silty clay layer as the research object,the evolution laws for the strength and frost heave deformation of artificially frozen silty clay affected by such factors as freezing temperature,moisture content and confining pressure were deeply studied through laboratory tests.Results indicate that the freezing temperature,moisture content,and confining pressure significantly affect the growing trend and failure mode of stress-strain curves.The relevance of the triaxial shear strength and elastic modulus with the freezing temperature,moisture content and confining pressure presents different evolution trends due to the coupling effects of the three.Under unidirectional freezing mode,the frost heave deformation of artificially frozen silty clay reaches the maximum once the temperature field reaches a constant temperature gradient.There is a better linear regression relationship between frost heave ratio and freezing temperature.Moreover,the frost heave ratio of silty clay under the condition of external water supply is much greater than that under the closed condition without water supply.In the engineering practice of artificial ground freezing technology,freezing temperature,moisture content and the buried depth of strata are the three indicators for ensuring the design strength of freezing wall,controlling surface deformation and preventing structure from fracture,water seepage or mud leakage.
Motivated by the application and development of artificial freezing method in subway engineering,with the silty clay layer as the research object,the evolution laws for the strength and frost heave deformation of artificially frozen silty clay affected by such factors as freezing temperature,moisture content and confining pressure were deeply studied through laboratory tests.Results indicate that the freezing temperature,moisture content,and confining pressure significantly affect the growing trend and failure mode of stress-strain curves.The relevance of the triaxial shear strength and elastic modulus with the freezing temperature,moisture content and confining pressure presents different evolution trends due to the coupling effects of the three.Under unidirectional freezing mode,the frost heave deformation of artificially frozen silty clay reaches the maximum once the temperature field reaches a constant temperature gradient.There is a better linear regression relationship between frost heave ratio and freezing temperature.Moreover,the frost heave ratio of silty clay under the condition of external water supply is much greater than that under the closed condition without water supply.In the engineering practice of artificial ground freezing technology,freezing temperature,moisture content and the buried depth of strata are the three indicators for ensuring the design strength of freezing wall,controlling surface deformation and preventing structure from fracture,water seepage or mud leakage.
引文
[1]陈湘生,汪崇鲜,吴成义.典型人工冻结黏土三轴剪切强度准则的试验研究[J].建井技术,1998(4):1-7.(CHEN Xiangsheng,WANG Chongxian,WU Chengyi.Experimental Study on Three Axis Shear Strength Criterion of Typical Artificial Frozen Clay[J].Well Construction Technology,1998(4):1-7.in Chinese)
[2]姚直书,蔡海兵,程桦,等.采用长距离水平冻结暗挖法的浅埋大断面地铁隧道施工技术[J].中国铁道科学,2011,32(1):75-80.(YAO Zhishu,CAI Haibing,CHENG Hua,et al.Construction Technique for the Shallow-Buried Subway Tunnel with Large-Section by Long-Distance Horizontal Ground Freezing Method and Undermining Method[J].China Railway Science,2011,32(1):75-80.in Chinese)
[3]唐益群,洪军,杨坪,等.人工冻结作用下淤泥质黏土冻胀特性试验研究[J].岩土工程学报,2009,31(5):772-776.(TANG Yiqun,HONG Jun,YANG Ping,et al.Frost-Heaving Behaviors of Mucky Clay by Artificial Horizontal Freezing Method[J].Chinese Journal of Geotechnical Engineering,2009,31(5):772-776.in Chinese)
[4]杨更社,屈永龙,奚家米.白垩系地层煤矿立井冻结壁的力学特性及温度场研究[J].岩石力学与工程学报,2014,33(9):1873-1879.(YANG Gengshe,QU Yonglong,XI Jiami.Study of Mechanical Properties and Temperature Field of Frozen Wall in Cretaceous Strata[J].Chinese Journal of Rock Mechanics and Engineering,2014,33(9):1873-1879.in Chinese)
[5] LI Dongwei,FAN Juhong,WANG Renhe.Research on Visco-Elastic-Plastic Creep Model of Artificially Frozen Soil under High Confining Pressures[J].Cold Regions Science and Technology,2011,65(2):219-225.
[6] MARWAN Ahmed,ZHOU Mengmeng,ZAKI Abdelrehim M,et al.Optimization of Artificial Ground Freezing in Tunneling in the Presence of Seepage Flow[J].Computers and Geotechnics,2016,75(5):112-125.
[7] WATANAB Kunio,OSADA Yurie.Comparison of Hydraulic Conductivity in Frozen Saturated and Unfrozen Unsaturated Soils[J].Vadose Zone Journal,2016,15(5):1-7.
[8] HU Xiangdong,WANG Jintai,YU Ruizhi.Uniaxial Compressive and Splitting Tensile Tests of Artificially Frozen Soils in Tunnel Construction of Hong Kong[J].Journal of Shanghai Jiaotong University:Science,2013,18(6):688-692.
[9]张向东,刘家顺,张玉.基于邓肯—张的冻结粉质黏土本构模型的试验研究[J].固体力学学报,2014,35(2):150-159.(ZHANG Xiangdong,LIU Jiashun,ZHANG Yu.The Experimental Research on Constitutive Relationship of Frozen Silty Clay Based on the Duncan-Chang Model[J].Chinese Journal of Solid Mechanics,2014,35(2):150-159.in Chinese)
[10] ZHAO Xiaodong,ZHOU Guoqing,WANG Jianzhou.Deformation and Strength Behaviors of Frozen Clay with Thermal Gradient under Uniaxial Compression[J].Tunneling and Underground Space Technology,2013,38(9):550-558.
[11]孙立强,路江鑫,李恒,等.含水率和含盐量对人工冻土强度特性影响的试验研究[J].岩土工程学报,2015,37(增2):27-31.(SUN Liqiang,LU Jiangxin,LI Heng,et al.Influence of Water and Salt Contents on Strength of Artificially Frozen Soils[J].Chinese Journal of Geotechnical Engineering,2015,37(Supplement 2):27-31.in Chinese)
[12]孙谷雨,杨平,刘贯荣.南京地区冻结粉质黏土邓肯—张模型参数试验研究[J].岩石力学与工程学报,2014,33(增1):2989-2995.(SUN Guyu,YANG Ping,LIU Guanrong.Experimental Test on Constitutive Relationship of Nanjing Frozen Silty Clay Considering Duncan-Chang Model[J].Chinese Journal of Rock Mechanics and Engineering,2014,33(Supplement 1):2989-2995.in Chinese)
[13] WANG Dayan,MA Wei,CHANG Xiaoxiao,et al.Study on the Resistance to Deformation of Artificially Frozen Soil in Deep Alluvium[J].Cold Regions Science and Technology,2014,39(1):78-83.
[14] YAMAMOTO Yuko,SPRINGMAN Sarah M.Axial Compression Stress Path Tests on Artificial Frozen Soil Samples in a Triaxial Device at Temperatures Just Below 0℃[J].Canadian Geotechnical Journal,2014,51(10):1178-1195.
[15] WANG Tianliang,LIU Yaojun,YAN Han,et al.An Experimental Study on the Mechanical Properties of Silty Soils under Repeated Freeze-Thaw Cycles[J].Cold Regions Science and Technology.2015,112(4):51-65.
[16] KONRAD Jean-Marie,LEMIEUX N.Influence of Fines on Frost Heave Characteristics of a Well-Graded BaseCourse Material[J].Canadian Geotechnical Journal.2005,42(2):515-527.
[17]胡向东.上海灰黄色粉砂水泥改良土冻胀融沉性质实验[J].煤炭学报,2009,34(3):334-339.(HU Xiangdong.Laboratory Research on Properties of Frost Heave and Thaw Settlement of Cement-Improved Shanghais Grey-Yellow Silty Sand[J].Journal of China Coal Society,2009,34(3):334-339.in Chinese)
[18]程桦,姚直书,张经双,等.人工水平冻结法施工轨道冻胀与融沉效应模型试验研究[J].土木工程学报,2007,40(10):80-85.(CHENG Hua,YAO Zhishu,ZHANG Jingshuang,et al.A Model Test Study on the Effect of Freeze Heaving and Thaw Subsidence for Tunnel Construction with Artificial Horizontal Ground Freezing[J].China Civil Engineering Journal,2007,40(10):80-85.in Chinese)
[2]姚直书,蔡海兵,程桦,等.采用长距离水平冻结暗挖法的浅埋大断面地铁隧道施工技术[J].中国铁道科学,2011,32(1):75-80.(YAO Zhishu,CAI Haibing,CHENG Hua,et al.Construction Technique for the Shallow-Buried Subway Tunnel with Large-Section by Long-Distance Horizontal Ground Freezing Method and Undermining Method[J].China Railway Science,2011,32(1):75-80.in Chinese)
[3]唐益群,洪军,杨坪,等.人工冻结作用下淤泥质黏土冻胀特性试验研究[J].岩土工程学报,2009,31(5):772-776.(TANG Yiqun,HONG Jun,YANG Ping,et al.Frost-Heaving Behaviors of Mucky Clay by Artificial Horizontal Freezing Method[J].Chinese Journal of Geotechnical Engineering,2009,31(5):772-776.in Chinese)
[4]杨更社,屈永龙,奚家米.白垩系地层煤矿立井冻结壁的力学特性及温度场研究[J].岩石力学与工程学报,2014,33(9):1873-1879.(YANG Gengshe,QU Yonglong,XI Jiami.Study of Mechanical Properties and Temperature Field of Frozen Wall in Cretaceous Strata[J].Chinese Journal of Rock Mechanics and Engineering,2014,33(9):1873-1879.in Chinese)
[5] LI Dongwei,FAN Juhong,WANG Renhe.Research on Visco-Elastic-Plastic Creep Model of Artificially Frozen Soil under High Confining Pressures[J].Cold Regions Science and Technology,2011,65(2):219-225.
[6] MARWAN Ahmed,ZHOU Mengmeng,ZAKI Abdelrehim M,et al.Optimization of Artificial Ground Freezing in Tunneling in the Presence of Seepage Flow[J].Computers and Geotechnics,2016,75(5):112-125.
[7] WATANAB Kunio,OSADA Yurie.Comparison of Hydraulic Conductivity in Frozen Saturated and Unfrozen Unsaturated Soils[J].Vadose Zone Journal,2016,15(5):1-7.
[8] HU Xiangdong,WANG Jintai,YU Ruizhi.Uniaxial Compressive and Splitting Tensile Tests of Artificially Frozen Soils in Tunnel Construction of Hong Kong[J].Journal of Shanghai Jiaotong University:Science,2013,18(6):688-692.
[9]张向东,刘家顺,张玉.基于邓肯—张的冻结粉质黏土本构模型的试验研究[J].固体力学学报,2014,35(2):150-159.(ZHANG Xiangdong,LIU Jiashun,ZHANG Yu.The Experimental Research on Constitutive Relationship of Frozen Silty Clay Based on the Duncan-Chang Model[J].Chinese Journal of Solid Mechanics,2014,35(2):150-159.in Chinese)
[10] ZHAO Xiaodong,ZHOU Guoqing,WANG Jianzhou.Deformation and Strength Behaviors of Frozen Clay with Thermal Gradient under Uniaxial Compression[J].Tunneling and Underground Space Technology,2013,38(9):550-558.
[11]孙立强,路江鑫,李恒,等.含水率和含盐量对人工冻土强度特性影响的试验研究[J].岩土工程学报,2015,37(增2):27-31.(SUN Liqiang,LU Jiangxin,LI Heng,et al.Influence of Water and Salt Contents on Strength of Artificially Frozen Soils[J].Chinese Journal of Geotechnical Engineering,2015,37(Supplement 2):27-31.in Chinese)
[12]孙谷雨,杨平,刘贯荣.南京地区冻结粉质黏土邓肯—张模型参数试验研究[J].岩石力学与工程学报,2014,33(增1):2989-2995.(SUN Guyu,YANG Ping,LIU Guanrong.Experimental Test on Constitutive Relationship of Nanjing Frozen Silty Clay Considering Duncan-Chang Model[J].Chinese Journal of Rock Mechanics and Engineering,2014,33(Supplement 1):2989-2995.in Chinese)
[13] WANG Dayan,MA Wei,CHANG Xiaoxiao,et al.Study on the Resistance to Deformation of Artificially Frozen Soil in Deep Alluvium[J].Cold Regions Science and Technology,2014,39(1):78-83.
[14] YAMAMOTO Yuko,SPRINGMAN Sarah M.Axial Compression Stress Path Tests on Artificial Frozen Soil Samples in a Triaxial Device at Temperatures Just Below 0℃[J].Canadian Geotechnical Journal,2014,51(10):1178-1195.
[15] WANG Tianliang,LIU Yaojun,YAN Han,et al.An Experimental Study on the Mechanical Properties of Silty Soils under Repeated Freeze-Thaw Cycles[J].Cold Regions Science and Technology.2015,112(4):51-65.
[16] KONRAD Jean-Marie,LEMIEUX N.Influence of Fines on Frost Heave Characteristics of a Well-Graded BaseCourse Material[J].Canadian Geotechnical Journal.2005,42(2):515-527.
[17]胡向东.上海灰黄色粉砂水泥改良土冻胀融沉性质实验[J].煤炭学报,2009,34(3):334-339.(HU Xiangdong.Laboratory Research on Properties of Frost Heave and Thaw Settlement of Cement-Improved Shanghais Grey-Yellow Silty Sand[J].Journal of China Coal Society,2009,34(3):334-339.in Chinese)
[18]程桦,姚直书,张经双,等.人工水平冻结法施工轨道冻胀与融沉效应模型试验研究[J].土木工程学报,2007,40(10):80-85.(CHENG Hua,YAO Zhishu,ZHANG Jingshuang,et al.A Model Test Study on the Effect of Freeze Heaving and Thaw Subsidence for Tunnel Construction with Artificial Horizontal Ground Freezing[J].China Civil Engineering Journal,2007,40(10):80-85.in Chinese)