平面应变条件下黄土剪切破坏与屈服特性研究

《平面应变条件下黄土剪切破坏与屈服特性研究》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。

1、密级公开１分类号ＴＵ４４４戀Ａ京ＸＩＡＮＴＥＣＨＮＯＬＯＧＩＣＡＬＵＮＩＶＥＲＳＩＴＹ硕士学位论文题目：平面应变条件下黄土剪切破坏与屈服特性研究作者：王智指导教师：李宝平副教授张玉讲师申请学位学科：岩土工程２０１８年５月１１日＊密级公开分类号TU444XI’ANTECHNOLOGICALUNIVERSITY硕士学位论文题目:平面应变条件下黄土剪切破坏与屈服特性研究作者：王智指导教师：李宝平副教授张玉讲师申请学位学科：岩土工

2、程2018年5月11日（3）通过η-ɛs关系曲线的首、尾切线的交点确定剪切屈服点，屈服剪应力比范围介于0.02—0.19之间，且随含水率或围压升高而降低，随初始固结应力比增大而升高。原状黄土的屈服不仅与含水率、围压及初始固结应力比有关，也与其原生结构强度和竖向裂隙特性有关。（4）原状黄土破坏时的应力条件与强度均高于屈服时。破坏及屈服时的中主应力和中主应力系数均随含水率的升高而减小，随围压或初始固结应力比的升高而增大，破坏时中主应力变化规律更明显；破坏及屈服时的中主应力系数均随固结应力比越大，含水

3、率与塑限大小的关系以及试验围压的大小对破坏和屈服时中主应力系数的变化规律有显著影响，破坏中主应力系数变化规律性较强；破坏中主应力系数范围为0.15—0.45，屈服中主应力系数范围为0.03—0.25。（5）依据试验数据绘制出莫尔圆及强度包络线，可知粘聚力在含水率超过塑限时衰减明显，随初始固结应力比增大而线性衰减；内摩擦角随含水率升高而线性衰减，随初始固结应力比增大而线性升高。关键词：平面应变试验；原状黄土；剪切变形；破坏强度；屈服强度duringshearingprocess.Withthein

4、creaseofwatermoistureorconfiningpressure,thecurvilinearformschangedfromweakhardeningtostronghardeningorapproximatelylineargradually;Thehigherofinitialconsolidationstressratiomakestheintermediateprincipalstressincrease,butmaksesthecoefficientofinterme

5、diateprincipalstressdecreases.(2)Thelateraldeformationofintactloessismainlylateralexpansionunderlowconfinementconditions,andmoreobviousduringlowermoisturecontentorhigherinitialconsolidationstressratio.Thelateralcontractionembodiedunderhighconfinement

6、conditionsmainly,anddividedintotwotypes:lateralexpansionafterthepeakpointoflateralcontractionorlateralcontractionconstantly,thelatterappearsunderanisotropicconsolidation,andlateraldeformationisgreaterunderanisotropicconsolidation.Thelateralcontractio

7、nismoreobviouslywithincreasingofinitialconsolidationstressratio;Theintactloessmainlyshowsshearcontraction,andshearcontractionfirstandthensheardilatationunderlowconfiningpressureandmoisturecontentconditionsmerely,shearcontractionismoreobviouswiththein

8、creaseofwatermoistureorconfiningpressure,alsoobviouswiththesmallerconsolidationstressratio,butonthecontraryunderhigherconfiningpressure.(3)Theshearyieldpointisdeterminedbytheintersectionpointoftheheadandtailtangentlineofη-ɛsrelationcurve,theyieldshea