新疆昭苏县草甸土的工程性质试验研究

发布时间：2018-07-10 13:51

本文选题：新疆 + 草甸土　；参考：《岩土工程学报》2016年03期

【摘要】：由于目前对草甸土的工程性质了解甚少,一方面引起了草甸土与草炭土、泥炭等的混淆,另一方面导致了在设计过程中不知如何选择相应的处治措施。鉴于此,以新疆伊犁昭苏县草甸土层为研究对象,参照一般土体的室内土工试验方法,测试了草甸土的比重、重度、烧失量、渗透系数、抗剪强度、无侧限抗压强度等物理力学指标,并将试验结果与国内外草炭土、泥炭、泥炭质土的工程特性进行了对比分析。结果表明:按照有机质含量分类,新疆昭苏县草甸土属于泥炭质土;其含水率处于泥炭质土的低限附近,而重度则高于一般泥炭和泥炭质土的重度,具有较好的渗透性、很高的压缩性;草甸土中的草根可以显著提高土体的黏聚力,但对内摩擦角的影响不明显;无侧限抗压强度试验过程中草甸土未发生类似于一般黏土的剪切破坏,而是产生了很大的压缩变形和鼓胀变形;草甸土在受荷载后主固结沉降完成很快,其主固结系数随着固结压力的增大线性减小;当固结压力超过100 k Pa时,草甸土的主固结比较小,说明此时草甸土的次固结变形量不容忽视,地基沉降计算中应予以考虑。
[Abstract]:Because of little understanding of the engineering properties of meadow soil at present, it has caused the confusion of meadow soil, peat soil, peat and so on. On the other hand, it leads to the choice of the corresponding treatment measures in the process of design. In view of this, the soil layer of meadow in Zhaosu County, Yili, Xinjiang is taken as the research object, and the indoor soil test method of general soil is used. The physical and mechanical indexes of meadow soil, such as gravity, severity, burning loss, permeability coefficient, shear strength, and unconfined compression strength, were tested and compared with the engineering properties of peat soil, peat and peat soil at home and abroad. The results showed that the meadow soil in Zhaosu County, Xinjiang, belongs to peat soil according to the classification of organic matter. The water content is near the low limit of the peat soil, and the severe is higher than the severe peat and peat soil. It has good permeability and high compressibility. The grass roots in meadow soil can significantly improve the cohesive force of soil, but the influence on the internal friction angle is not obvious; the meadow soil is not similar in the process of unconfined compression strength test. The shear deformation and swelling deformation of the clay are caused by the shear failure of the clay. The main consolidation coefficient of meadow soil is fast after loading, and the main consolidation coefficient decreases linearly with the increase of the consolidation pressure. When the consolidation pressure exceeds 100 K Pa, the main solid knot of the meadow soil is relatively small, indicating the secondary consolidation deformation of the meadow soil at this time. It should not be ignored and should be considered in the calculation of foundation settlement.
【作者单位】：北京交通大学土木建筑工程学院;轨道工程北京市重点实验室;北京市轨道交通线路安全与防灾工程技术研究中心;交通运输部公路科学研究院;
【基金】：国家自然科学基金项目(51108024,41371081) 中央高校基本科研业务费项目(2014JBM093)
【分类号】：TU43

【参考文献】