非饱和重塑黄土三轴蠕变试验研究

Triaxial Creep Tests of Unsaturated Remoulded Loess

为研究陕西咸阳扶风地区黄土边坡的稳定性,利用SR-60型双联三轴蠕变仪针对非饱和重塑黄土进行了三轴固结排水蠕变试验。试验结果表明:试样含水率、固结围压和偏应力水平对蠕变变形具有明显的影响。表现为:当含水率较大、固结围压较小时,蠕变变形量大,蠕变现象明显;当其他条件一定时,在偏应力水平较大条件下,试样变形大,蠕变现象明显。在数据分析的基础上建立了经验模型,并与Singh-Mitchell和Mesri模型对比后发现,新模型具有精度高、参数少且参数容易获得等优点,能较好地模拟该地区黄土蠕变过程。

To investigate the stability of loess slope in Fufeng district of Shaanxi province,we carried out drained triaxial creep tests of unsaturated remoulded loess by SR-60,a traixial creep instrument. Test results show that the creep characteristics of loess is obviously influenced by water content,confining pressure and consolidation pressure. The creep strain grows much bigger,and the creep phenomenon is quite obvious when the water content is higher and confining pressure is lower. Meanwhile,with other condition invariable,the creep strain increases with the growing of consolidation pressure. On the basis of analyzing test data,we proposed an empirical creep model and compared it with Singh-Mitchell model and Mesri model. The comparison reveals that the model is of high accuracy and easy-obtained parameters in simulating the creep characteristics of loess.