太原黄土含水率对邓肯-张模型参数影响研究

Study on Influence of Water Content in Taiyuan Loess on Duncan-Chang Model Parameters

为研究太原黄土的工程力学特性以及分析含水率对黄土整体稳定性的影响,对土样进行不同初始条件的室内三轴试验,将试验结果用邓肯-张模型进行拟合分析,获得了太原黄土的邓肯-张模型参数及其随含水率变化的规律。结果表明,随着含水率增大,黄土的抗剪强度、黏聚力和内摩擦角均有减小趋势,初始含水率较小时,试样有应变软化趋势,表现出剪胀现象。切线弹性模量及体积变形模量都随含水率的减小而增大,随应变的增大而迅速减小。在工程建设中要严格控制黄土的含水率等相关指标。

In order to study the engineering mechanical characteristics of Taiyuan loess and analyze the influence of water content on loess stability, this paper carries out indoor triaxial test on soil sample under different initial conditions and makes fitting analysis of test results with Duncan-Chang Model to obtain the rule of Duncan-Chang Model parameters changes with water content of Taiyuan loess. It is indicated from result that loess shearing resistance, cohesive strength and inner friction angle tend to reduce with the increase of water content; the test sample is subject to strain softening under shearing expansion with less initial water content. Tangent modulus of elasticity and volume modulus of deformation increase with the reduction of water content and rapidly reduce with the increase of strain. Therefore, relevant indexes of loess such as water content shall be strictly controlled in engineering construction.