冻融循环对永和原状黄土影响的试验研究

山西省内黄土分布广阔,对山西黄土地质灾害进行研究可以减少人民和国家的经济财产损失,对灾害的预防有重要意义。以山西省临汾市永和县阁窑沟渠原状黄土为试验对象,通过对比在封闭情况下冻融循环前后原状黄土的抗剪强度、黏聚力、内摩擦角的物理力学性质,研究原状黄土冻融后的变化规律。实验结果表明:冻融后土体含水率降低,黏聚力减小;土体在经历反复冻融后土体结构性减弱,抗剪强度降低;内摩擦角在围压较小时原始土大于冻融后土体,随着围压的增大冻融后土体的内摩擦角变大并大于原始土。最后通过室内试验的研究,分析了阁窑沟渠发生的滑坡与土体的冻融循环之间的联系,也为减少类似地质灾害的发生提出几点建议。

Test research on influence of freezing and thawing cycle on undisturbed loess in Yonghe

Shanxi Province has a wide distribution of loess , It is important to study the geological hazards of Shanxi loess in order to reduce the property lose and disaster prevention of the people and the country. This paper in Yong He Ge Yao Gou undisturbed loess as the test object by comparing in a closed situation of freezing and thawing cycle of intact loess shear strength cohesive internal friction angle .and the variation law of undisturbed loess after freezing and thawing was studied. Experimental results show that: the moisture content of soil and the cohesive force is decreased, The soil structure is weakened and shear strength is reduced after repeated freezing and thawing. when the confining pressure is lower,the internal friction angle is larger than that of the original soil, with the increase of confining pressure,the internal friction angle of the soil comes to inverse. Finally, the relationship between the landslide and the freezing and thawing cycles of the channel of Ge Yaogou is discussed through the analysis of the laboratory experiment.On the other hand, in order to reduce the occurrence of similar geological disasters ,some suggestions are put forward.