重塑黄土三轴蠕变特性研究及模型分析

采用SR-6型三轴蠕变仪对陕西省泾阳县某边坡重塑黄土进行了一系列室内三轴固结排水蠕变试验，着重研究了90%压实度下重塑黄土在不同含水率与围压下的蠕变特性，并依据试验资料建立了两种经验蠕变模型。结果表明：该地区黄土具有明显的流变特性，总体呈非线性衰减蠕变；围压与含水率均对蠕变特性有着显著的影响，土样在小围压、大含水率的条件下蠕变现象明显且蠕应变较大；同等荷载增量引起的应变增量的突然放大，预示着该级荷载已经超过土体的屈服应力值，土样产生黏塑性变形；两种模型的建立均能恰当地描述土体在20% ~ 65%偏应力水平下的蠕变特性，且模型简单，参数易得。

Research on triaxial creep characteristics and models of remolded loess

A series of laboratory consolidated drained triaxial creep tests is performed with triaxial creep apparatus SR-6 to investigate the behaviors of the remolded loess from a loess slope of Jingyang in Shaanxi province. The tests focus on studying the creep characteristics of remolded loess with a 90% compaction degree under different water contents and confining pressures. Based on the experimental data, two different empirical models are developed. The results indicate that the loess in this area has obvious rheological properties, general showing a nonlinear attenuation creep. The creep behaviors of the loess are significantly influenced by confining pressure and water content. When the sample is under the conditions of smaller confining pressure and higher moisture, it exhibits notable creep companied by the bigger creep strain. A sudden increase in strain increment caused by equal load increment indicates that this level of load exerted on sample has exceeded the yield stress value of soil, and soil sample will produce sticky plastic deformation. Both models can aptly describe creep properties of loess under the partial stress levels between 20% and 65% and also have fewer parameters and easier method of obtaining parameters.