湿陷性黄土增（减）湿变形性状试验研究

【作者】 张茂花；

【导师】 谢永利； 刘保健；

【作者基本信息】 长安大学 ， 岩土工程， 2002， 硕士

【摘要】 本文依托国家自然科学基金项目《黄土湿陷的大变形理论描述与数值仿真分析》（NO.598780401），在广泛总结前人有关黄土湿陷变形研究成果的基础上，针对过去对黄土湿陷性的研究多侧重于充分浸水饱和后的湿陷变形，而对增（减）湿到某一含水量情况下的增（减）湿变形却研究的较少，而且以往对黄土湿陷性的研究中采用的大都是双线法，很少有人采用单线法研究的现状，分别采用单线法和双线法对甘肃陇西原状Q₃黄土进行了增、减湿情况下的单轴压缩试验和三轴剪切试验。 通过对几种方法得出的试验结果进行对比和分析，总结出黄土的湿陷变形和抗剪强度指标随饱和度以及压力变化的规律，借以描述湿陷性黄土在增（减）湿过程中的湿陷变形性状、强度特性以及不同应力路径对黄土变形特性的影响；按不同的浸水路径和受力方向对土样进行单轴压缩试验，证明了湿陷与浸水路径无关的结论以及湿陷性黄土显著的各向异性特征。 最后建立了湿陷性黄土增（减）湿变形的本构模型，为以后的工程设计和数值计算提供了依据。更多还原

【Abstract】 This paper is an important part of the scientific project <<Large-strain description and numerical imitation analysis for hydrocompaction of loess>> (authorized number:598780401). Based on the analysis of literatures about collapsing deformation of loess soil, aimed at the actuality of past research on collapsible loess that emphasized particularly on collapsing deformation after adequately inundated and saturated, but paid little attention to the research on the moistening (drying) deformation when dampened (dried) to some humidity, and in the past, the bilinear method was mainly used instead of the single-track method, this paper uses both single-track method and bilinear method to carry out monaxial compression test and triaxial shear test on undisturbed loess( Q3) comes from Longxi area in Gansu province.Through contrasting and analysing the experimental results from these methods, the paper summarizes the regularity of collapsing deformation and the shear strength index changes with the degree of saturation and stress, describes the collapsing deformation properties and strength characters of the collapsible loess in the course of moistening and drying, and describes the influence to collapsing deformation of loess from different paths of stress. Through performing monaxial compression test on samples with different paths of inundation and direction of press, proves the conclusion that collapse has nothing to do with the path of inundation and the collapsible loess has the prominent anisotropy characters.Finally ,the author establishes the moistening and drying constitutive model of collapsible loess, which provides basis for future engineering design and numerical calculation.更多还原