基于JohnsonCook模型的冻土动态本构关系.pdf

第44卷增刊2 2012年12月四川I大学学报(工程科学版) JOURNAL OF SICHUAN UNIVERSITY(ENGINEERING SCIENCE EDITION) 文章编号:(2012)增刊2-0019-04 基于Johnson—Cook模型的冻土动态本构关系张海东1’2,朱志武1’h,康国政1,马悦1 (,四川成都,610031; ,甘肃兰州,730000) 摘要:采用分离式霍普金森压杆(SHPB),对于一17℃冻土进行了应变率约350、600、800、1 000和1 200S“的单轴冲击实验。获得了其相应应变率下的应力应变关系。发现其没有明显的屈服现象,具有显著的应变率效应,其峰值应力与最终应变均随加载应变率增大而增大,并且具有一定的线性关系。, 描述一17℃冻土的应力应变关系,发现在600~l 200S“的加载应变率范围内,该模型具有较好的适用性。关键词:冻土;冲击;分离式霍普金森压杆;应变率效应;损伤中图分类号:035;P642 文献标志码:A Dynamic C:onstitutive Relation ofFrozen SoilBased on Johnson-Cook Model ZHANG Hai—don91一,ZHU Zhi—WUl'¨,KANG Guo-zhen91,MA Yuel ( ofMechanics and Eng.,Southwest Jiaotong Univ.,Cherlgdu 610031,China; Key Frozen SoilEng.,CAREERI,CAS,lamzhou 730000,China) Abstract:A splitHopkinson pressure bar(SHPB)was employed investigate thedynamic behavior frozen soilunder uni- pression testwith strain rates from 350 s一1 200 stress—strain relations various strain rates were ob. frozen soildidn’tyieldduring strength offrozensoilshowed positive strain—ratesensitivity over therange ofstrain rates employed inthepresent Johnson—Cook model withdamage was introduced todescribe thedynamic behavior of一17℃frozen model works well thestrain rate range from600 200 S~. Key words:frozen soil;impact;SHPB;strain rat