黄土三轴蠕变试验与Singh-Mitchell模型修正

为研究陕西省咸阳市扶风地区黄土边坡的稳定性,利用SR-60型双联三轴蠕变仪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,蠕变形变量大,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。同时,利用Singh-Mitchell模型和修正后的Singh-Mitchell模型对试验数据进行拟合发现,修正后的模型克服了偏应力水平对原始模型模拟精度的限制,拟合精度高,且后期趋势基本吻合,能较好地模拟该地区黄土蠕变过程。

Loess Triaxial Creep Test and Revised Singh Mitchell Model

To investigate the stability of loess slope in Fufeng district of Shaanxi Province, a series of drained triaxial creep tests of loess were taken by SR 60, a traixial creep instrument. The tests results show that the creep characteristics of loess are obviously influenced by water content, confining press and consolidation pressure. The creep strain grows much bigger, and the creep phenomenon is quite obvious when the water content is higher and the confining pressure is lower. Under the given conditions, the creep strain increases with the growing of consolidation pressure. The Singh Mitchell and revised Singh Mitchell creep models were used to simulate the test results. It can be told from the results that the revised model overcomes the restriction of deviator stress level on original model, and the simulation precision is relatively higher, as well as the similar trend, which indicates that the revised creep model could simulate the creep characteristics of loess well.