黄土固结蠕变特性试验研究

LABORATORY TEST OF LOESS FOR CONSOLIDATION CREEP BEHAVIOR

基于杨凌地区黄土的单向固结试验资料,分别研究了加载条件下原状黄土和扰动黄土的固结蠕变特性,由试验数据整理分析出不同含水率、不同固结压力下的固结蠕变曲线簇,根据蠕变曲线形态特征,推导出单向固结条件下黄土的应变-时间关系并拟合得到该关系中的参数,在分析参数与固结压力之间关系的基础上推导出黄土的一维固结蠕变本构关系,经试验证明,该关系能较好的描述杨凌地区黄土的固结蠕变特性。另外,基于试验资料以及Buisman次固结系数的概念,分析出次固结系数与固结压力之间的定量关系,为确定固结压力对黄土次固结特性的影响提供了一种新途径。

An one -dimensional consolidation test under separated loads is conducted to obtain the characteristic creep curves of loess in Yangling Distirct. According to the typical behavior of stress - strain curves of loess under one - dimensional consolidation, an one - dimensional consolidation creep constitutive model is obtained from the relation of parameters and consolidation stress. The relation better simulates the creep characteristics of loess in Yan- gling District with model test. Besides, based on the experimental results and the secondary consolidation coefficient proposed by Buisman, the relation between the secondary consolidation coefficient and the consolidation stress is obtained. Therefore, a new method of confirming the influence of consolidation stress on the secondary consolidation characteristics is suggested.