冻土动强度特性试验研究
|
摘要
在围压为0.3～16 MPa,频率为2 Hz,温度为-4和-6℃条件下,通过一系列恒应力幅循环动荷载试验,发现冻土动强度的变化不仅跟破坏振次的大小有关,而且与围压、循环荷载作用下土体吸收的有效能量(损失能)之间也存在一定关系。根据损失能获得试样温度的变化,将冻土动强度与温度直接联系起来,表明振动荷载作用下损失能累积造成的温度额外升高是控制冻土动强度变化特性的主要因素之一。
Dynamic strength characteristics of frozen silty clay was studied using triaxial cycle tests with the constant stress amplitude under confining pressures varying between 0.3 MPa and 16.0 MPa,at temperatures of-4℃ and-6℃ and a frequency of 2 Hz.It was shown that the dynamic strength depended not only on the number of vibrations and confining pressures,but also on loss of energy resulted from cyclic loading.According to the relationship among the dynamic strength,loss of energy and variation of temperature in specimens,an approximate formula was obtained,indicating that the loss of dynamic strength was influenced by confining pressures and the loss of energy.Thus,one of the key factors controlling the dynamic strength was the raised temperature resulted from the accumulative energy under cyclic loading.
Dynamic strength characteristics of frozen silty clay was studied using triaxial cycle tests with the constant stress amplitude under confining pressures varying between 0.3 MPa and 16.0 MPa,at temperatures of-4℃ and-6℃ and a frequency of 2 Hz.It was shown that the dynamic strength depended not only on the number of vibrations and confining pressures,but also on loss of energy resulted from cyclic loading.According to the relationship among the dynamic strength,loss of energy and variation of temperature in specimens,an approximate formula was obtained,indicating that the loss of dynamic strength was influenced by confining pressures and the loss of energy.Thus,one of the key factors controlling the dynamic strength was the raised temperature resulted from the accumulative energy under cyclic loading.
引文
[1]CHAICHANAVONG T.Dynamic properties of ice and frozen clay under cyclic triaxial loading conditions[D].Dept of Civil and Sanitary Engineering,Michigan State Univ,East Lansing,1976:460.
[2]VINSON T S,LI J C.Dynamic properties of frozen sand under simulated earthquake loading conditions[C]//Proceedings of the Seventh World Conference on Earthquake Engineering,Turkish National Committee on Earthquake Engineering,Istanbul,1980(3):65–72.
[3]何平,朱元林,张家懿,等.饱和冻结粉土的动弹模和动强度[J].冰川冻土,1993,15(1):170–174.(HE Ping,ZHU Yuan-lin,ZHANG Jia-yi,et al.Dynamic elastic modulus and dynamic strength of saturated frozen silt[J].Journal of Glaciology and Geocryology,1993,15(1):170–174.(in Chinese))
[4]徐学燕,仲丛利,陈亚明.冻土的动力特性研究及其参数确定[J].岩土工程学报,1998,20(5):77–81.(XU Xue-yan,ZHONG Cong-li,CHEN Ya-ming,et al.The dynamic characteristic of frozen soil and determination of parameters[J].Chinese Journal of Geotechnical Engineering,1998,20(5):77–88.(in Chinese))
[5]徐春花,徐学燕,邱明国,等.循环荷载下冻土的动阻尼比试验研究[J].哈尔滨建筑大学学报,2002,35(6):22–25.(XU Chun-hua,XU Xue-yan,QIU Ming-guo,et al.Test study on the damping ratio of frozen soil under cyclic vibrating load[J].Journal of Harbin University of Civil Engineering and Architecture,2002,35(6):22–25.(in Chinese))
[6]沈忠言,张家懿.振动荷载作用下饱和冻结粉土的单轴抗压强度[J].冰川冻土,1996,18(2):162–169.(SHENG Zhong-yan,ZHANG Jia-yi.The uniaxial compressive strength of frozen saturated silt under vibrating load[J].Journal of Glaciology and Geocryology,1996,18(2):162–169.(in Chinese))
[7]沈忠言,张家懿.冻结粉土的动强度特性及其破坏准则[J].冰川冻土,1997,19(2):141–148.(SHEN Zhong-yan,ZHANG Jia-yi.Dynamic strength characteristic and failure criterion of frozen silt[J].Journal of Glaciology and Geocryology,1997,19(2):141–148.(in Chinese))
[8]吴志坚,马巍,等.地震荷载作用下温度和围压对冻土强度影响的试验研究[J].冰川冻土,2003,25(6):648–652.(WU Zhi-jian,MA Wei,et al.Laboratory study on the effect of temperature and confining pressure on strength of frozen soil under seismic dynamic loading[J].Journal of Glaciology and Geocryology,2003,25(6):648–652.(in Chinese))
[9]王丽霞,凌贤长,徐学燕,等.青藏铁路冻结粉质黏土动静三轴试验对比[J].岩土工程学报,2005,27(2):202–205.(WANG Li-xia,LING Xian-zhang,XU Xue-yan,et al.Comparison of dynamic and static triaxial test on frozen silty clay of Qinghai-Tibet Railway[J].Chinese Journal of Geotechnical Engineering,2005,27(2):202–205.(in Chinese))
[10]朱元林,何平,张家懿.冻土在振动荷载下的三轴蠕变模型[J].自然科学进展,1998,8(1):60–62.(ZHU Yuan-lin,HE Ping,ZHANG Jia-yi.Triaxial creep model of frozen soil under dynamic loading[J].Progress in Natural Science,1998,8(1):60–62.(in Chinese))
[11]徐春华,徐学燕,耿永常,蒲毅彬.振动荷载作用下冻土结构弱化机理研究[J].哈尔滨工业大学学报,2003,35(12):1513–1429.(XU Chun-hua,XU Xue-yan,GENG Yon-chang,PU Yi-bin.Structural degrade analysis of frozen soil under vibrating load[J].Journal of Harbin Institute of Technology,2003,35(12):1513–1429.(in Chinese))
[12]张淑娟,赖远明,张明义,俞文兵.动荷载作用下冻土温度变化及其强度损失探讨[J].冰川冻土,2006,28(1):131–135.(ZHANG Shu-juan,LAI Yuan-ming,ZHANG Ming-yi,YU Wen-bing.Temperature change and strength descent of frozen soils under dynamic loading[J]Journal of Glaciology and Geocryology,2006,28(1):131–135.(in Chinese))
[13]MA W,WU Z W,ZHANG L X.Analyses of process on the strength decrease in frozen soils under high confining pressures[J].Cold Regions Science and Technology,1999,29(1):1–7.
[14]LADANYI B.A strength sensitivity index for assessing climate warming effects on permafrost[J].Cold Regions Engineering,1996:35–45.
[2]VINSON T S,LI J C.Dynamic properties of frozen sand under simulated earthquake loading conditions[C]//Proceedings of the Seventh World Conference on Earthquake Engineering,Turkish National Committee on Earthquake Engineering,Istanbul,1980(3):65–72.
[3]何平,朱元林,张家懿,等.饱和冻结粉土的动弹模和动强度[J].冰川冻土,1993,15(1):170–174.(HE Ping,ZHU Yuan-lin,ZHANG Jia-yi,et al.Dynamic elastic modulus and dynamic strength of saturated frozen silt[J].Journal of Glaciology and Geocryology,1993,15(1):170–174.(in Chinese))
[4]徐学燕,仲丛利,陈亚明.冻土的动力特性研究及其参数确定[J].岩土工程学报,1998,20(5):77–81.(XU Xue-yan,ZHONG Cong-li,CHEN Ya-ming,et al.The dynamic characteristic of frozen soil and determination of parameters[J].Chinese Journal of Geotechnical Engineering,1998,20(5):77–88.(in Chinese))
[5]徐春花,徐学燕,邱明国,等.循环荷载下冻土的动阻尼比试验研究[J].哈尔滨建筑大学学报,2002,35(6):22–25.(XU Chun-hua,XU Xue-yan,QIU Ming-guo,et al.Test study on the damping ratio of frozen soil under cyclic vibrating load[J].Journal of Harbin University of Civil Engineering and Architecture,2002,35(6):22–25.(in Chinese))
[6]沈忠言,张家懿.振动荷载作用下饱和冻结粉土的单轴抗压强度[J].冰川冻土,1996,18(2):162–169.(SHENG Zhong-yan,ZHANG Jia-yi.The uniaxial compressive strength of frozen saturated silt under vibrating load[J].Journal of Glaciology and Geocryology,1996,18(2):162–169.(in Chinese))
[7]沈忠言,张家懿.冻结粉土的动强度特性及其破坏准则[J].冰川冻土,1997,19(2):141–148.(SHEN Zhong-yan,ZHANG Jia-yi.Dynamic strength characteristic and failure criterion of frozen silt[J].Journal of Glaciology and Geocryology,1997,19(2):141–148.(in Chinese))
[8]吴志坚,马巍,等.地震荷载作用下温度和围压对冻土强度影响的试验研究[J].冰川冻土,2003,25(6):648–652.(WU Zhi-jian,MA Wei,et al.Laboratory study on the effect of temperature and confining pressure on strength of frozen soil under seismic dynamic loading[J].Journal of Glaciology and Geocryology,2003,25(6):648–652.(in Chinese))
[9]王丽霞,凌贤长,徐学燕,等.青藏铁路冻结粉质黏土动静三轴试验对比[J].岩土工程学报,2005,27(2):202–205.(WANG Li-xia,LING Xian-zhang,XU Xue-yan,et al.Comparison of dynamic and static triaxial test on frozen silty clay of Qinghai-Tibet Railway[J].Chinese Journal of Geotechnical Engineering,2005,27(2):202–205.(in Chinese))
[10]朱元林,何平,张家懿.冻土在振动荷载下的三轴蠕变模型[J].自然科学进展,1998,8(1):60–62.(ZHU Yuan-lin,HE Ping,ZHANG Jia-yi.Triaxial creep model of frozen soil under dynamic loading[J].Progress in Natural Science,1998,8(1):60–62.(in Chinese))
[11]徐春华,徐学燕,耿永常,蒲毅彬.振动荷载作用下冻土结构弱化机理研究[J].哈尔滨工业大学学报,2003,35(12):1513–1429.(XU Chun-hua,XU Xue-yan,GENG Yon-chang,PU Yi-bin.Structural degrade analysis of frozen soil under vibrating load[J].Journal of Harbin Institute of Technology,2003,35(12):1513–1429.(in Chinese))
[12]张淑娟,赖远明,张明义,俞文兵.动荷载作用下冻土温度变化及其强度损失探讨[J].冰川冻土,2006,28(1):131–135.(ZHANG Shu-juan,LAI Yuan-ming,ZHANG Ming-yi,YU Wen-bing.Temperature change and strength descent of frozen soils under dynamic loading[J]Journal of Glaciology and Geocryology,2006,28(1):131–135.(in Chinese))
[13]MA W,WU Z W,ZHANG L X.Analyses of process on the strength decrease in frozen soils under high confining pressures[J].Cold Regions Science and Technology,1999,29(1):1–7.
[14]LADANYI B.A strength sensitivity index for assessing climate warming effects on permafrost[J].Cold Regions Engineering,1996:35–45.
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心