作者：张海东1, 朱志武1,2, 刘煦1
作者单位：1. 西南交通大学力学与工程学院, 四川 成都 610031;
2. 冻土工程国家重点实验室, 甘肃 兰州 730000
关键词：冻土; 动态加载; 分离式霍普金森压杆; 单轴加载; 应变率效应
摘要：
为研究冻土单轴加载下的冲击动态力学性质,采用分离式霍普金森压杆(SHPB)在-28~-3℃不同负温下对人工冻土进行了应变率范围800~1 500 s-1的冲击实验。获得了人工冻土在不同温度与不同应变率下的应力应变关系,发现人工冻土具有显著的应变率效应和温度效应,即冻土动强度随应变率增大和温度的降低而增大。单轴高应变率加载下,冻土没有明显的屈服现象,加载后试样完全破坏。
Study on dynamic mechanical behaviors of frozen soil under uniaxial loading
ZHANG Hai-dong1, ZHU Zhi-wu1,2, LIU Xu1
1. School of Mechanics and Engineering, Southwest Jiaotong University, Chengdu 610031, China;
2. State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China
Abstract: A split Hopkinson pressure bar(SHPB) is employed to investigate the dynamics character of artificial frozen soil under uniaxial dynamic compression test at the temperature from-28℃ to-3℃ and strain rates from 800 to 1 500 s-1. The stress-strain curves at various strain rates and temperature were obtained. The compressive strength of frozen soil shows positive strain-rate and negative temperature sensitivity over the range of strain rates and temperature employed. The frozen soil didn't yield during the SHPB tests. The specimens were catastrophically damaged after the uniaxial SHPB tests.
Keywords: frozen soil; dynamic loading; SHPB; uniaxial compression; strain rate effect
2012, 38(3): 17-19 收稿日期: 2011-10-14;收到修改稿日期: 2011-12-27
基金项目: 国家自然科学基金项目(11172251)教育部博士点基金项目(20090184120001)冻土工程国家重点实验室开放基金项目(SKLFSE201001)
作者简介: 张海东(1988-),男,辽宁锦州市人,硕士研究生,专业方向为冻土冲击力学性质的研究。
参考文献
[1] 赵淑萍,朱元林,何平,等. 冻土动力学研究的现状与进展[J]. 冰川冻土,2002(10):681-685.
[2] 齐吉琳,马巍. 冻土的力学性质及研究现状[J]. 岩土力学,2010(1):133-143.
[3] 马芹永. 人工冻土动态力学特性研究现状及意义[J]. 岩土力学,2009(S1):10-14.
[4] Michael D, Furish. Measuring static and dynamic properties of frozen silty soils[R]. Albuquerque,1998:87185-1168.
[5] Moo Y L, Fossum A,Laurence S,et al. Frozensoil material testing and constitutive modeling[R]. Albuquerque,2002:87185-0751.
[6] 马芹永. 冻土在冲击荷载作用下动态力学行为的研究[D]. 北京:北京科技大学,2005:92-111.
[7] 陈柏生,胡时胜,马芹永,等. 冻土动态力学性能的实验研究[J]. 力学学报,2005(11):724-728.
[8] 王礼力. 应力波基础[M]. 2版. 北京:国防工业出版社,2005:46-47.
