原状黄土蠕变特性试验研究

以在陕西省杨凌区所采集的黄土样品为研究对象,对不同初始含水率的原状黄土进行了剪切蠕变试验,获取了蠕变曲线和蠕变特征参数,并研究了含水率、剪应力水平对蠕变特性的影响.结果表明,当含水率一定时,剪应力水平对黄土的蠕变特性有较大的影响,表现为剪应力愈大,黄土的蠕变应变愈大;当剪应力水平一定时,含水率对黄土蠕变特性影响明显,表现为含水率愈大,蠕变应变愈大.根据蠕变曲线特征,建立了原状黄土的蠕变本构模型,通过试验数据拟合得到本构模型中的参数.经验证,该模型能较好地模拟杨凌地区原状黄土的蠕变特性.

Experimental Study of the Cheep Behavior of Unsaturated Intact Loess

By taking the loess in Mangling District,Shaanxi Province as a research object,a direct shear creep test is conducted to obtain the char acteristic creep curve and parameters of intact loess under different water contents and analyze the influences of water content and shear stress on creep characteristics. Results indicate that at a given water content,shear stress obviously influences the creep characteristics. The higher shear stress, the greater creep strain of loess. At a given shear stress, water content obviously influences the creep charactristics. The higher water content,the bigger creep strain. According to the typical behavior of creep curve,a creep constitutive model and characteristic parameters are obtained by fitting test data. The model better simulates the creep characteristics of intact loess in Mangling District by model test.