建筑垃圾杂填土强度特性的试验研究和数值分析

发布时间：2019-05-22 22:34

【摘要】：建筑垃圾杂填土是由渣土、废旧混凝土、废旧砖石及其他废弃物组成的一种结构复杂、成分多样、多相的特殊土,不同于传统意义上的均质土。迄今,学术界对于建筑垃圾杂填土的研究主要集中在建筑垃圾的可循环利用和在道路市政工程上的应用,对杂填土强度特性的研究绝大多数集中在包含生活垃圾的城市固体垃圾,很少有对建筑垃圾杂填土强度特性的研究。本文主要通过室内试验和数值模拟两方面对建筑垃圾杂填土的强度特性进行研究。影响建筑垃圾杂填土的强度参数的因素有很多,而建筑垃圾杂填土的构成对强度参数起决定性作用。因此,本文对于建筑垃圾杂填土的强度特性的研究主要集中在不同比例组成成分对其强度参数的影响规律,主要包括试验研究与数值分析两部分。在试验研究中,通过对粉土、碎石土、砂土、粘性土及自行配制的建筑垃圾杂填土的大型直剪试验,得出了相应的强度参数,并对比分析得到初步结论:建筑垃圾杂填土的各组成成分对其强度参数是有影响的。以细粒土为基的建筑杂填土的强度参数与为基的成分土的强度参数相比,内摩擦角有所增加,粘聚力有所下降,粒径较大的颗粒土对细颗粒土的粘聚力的影响大于对内摩擦角的影响;以粗粒土为基的杂填土的强度参数与为基的成分土的强度参数相比,内摩擦角有所下降,粘聚力有所增加,粒径较小的颗粒土对粗颗粒土的内摩擦角的影响大于对粘聚力的影响;当建筑杂填土的各组组成成分比例接近时,强度参数介于各组成成分之间,且与中粒径土强度参数接近。对于内摩擦来说,细粒土对粗粒土的影响程度比粗粒土对细粒土强度参数的影响程度大;对于粘聚力来说,粗粒土对细粒土的影响程度比细粒土对粗粒土强度参数的影响程度大。在数值分析中,利用大型通用有限元软件ABAQUS对于室内试验的各类土进行直剪试验数值模拟,得出相应的强度参数,分析结果表明:数值模拟所得的强度参数与试验基本吻合,证明了本文采用的室内大型直剪试验和有限元模拟直剪试验可以作为测量建筑垃圾杂填土强度参数的两种有效手段;通过对数值模拟所得的强度参数进行对比分析,所得的规律与上述室内试验是基本一致的。本文探讨了不同比例组成成分对建筑垃圾杂填土强度参数的影响规律,可以作为工程上估计建筑垃圾杂填土强度参数的参考依据。
[Abstract]:Construction waste miscellaneous fill is a kind of special soil with complex structure, diverse composition and multiphase, which is composed of slag soil, waste concrete, waste brick and other wastes, which is different from homogeneous soil in the traditional sense. Up to now, the academic research on construction waste miscellaneous fill has mainly focused on the recyclable utilization of construction waste and its application in road municipal engineering. Most of the studies on the strength characteristics of miscellaneous fill focus on municipal solid waste including domestic waste, and few studies on the strength characteristics of construction waste mixed fill. In this paper, the strength characteristics of construction waste mixed fill are studied by laboratory test and numerical simulation. There are many factors that affect the strength parameters of construction waste miscellaneous fill, and the composition of construction waste miscellaneous fill plays a decisive role in the strength parameters. Therefore, the research on the strength characteristics of construction waste mixed fill mainly focuses on the influence of different proportion components on its strength parameters, including experimental research and numerical analysis. In the experimental study, the corresponding strength parameters are obtained through the large-scale direct shear tests of silt, gravel, sand, clayey soil and the mixed fill of construction waste prepared by ourselves. The preliminary conclusion is drawn from the comparative analysis that the components of construction waste miscellaneous fill have influence on its strength parameters. Compared with the strength parameters of the composite soil based on fine grain soil, the internal friction angle increases and the cohesion decreases. The effect of particle size on the cohesion of fine soil is greater than that of internal friction angle. Compared with the strength parameters of the composite soil based on coarse grain soil, the internal friction angle and cohesion of the mixed fill based on coarse grain soil are decreased, and the cohesion of the mixed fill based on coarse grain soil is higher than that of the composite soil based on coarse grain soil. The effect of small particle size on the internal friction angle of coarse soil is greater than that on cohesion. When the proportion of each component of building miscellaneous fill is close to each other, the strength parameters are between the components and close to the strength parameters of medium grain size soil. For internal friction, the influence of fine-grain soil on coarse-grain soil is greater than that of coarse-grain soil on the strength parameters of fine-grain soil. For cohesion, the influence of coarse soil on fine grain soil is greater than that of fine grain soil on strength parameters of coarse grain soil. In the numerical analysis, the numerical simulation of the direct shear test of all kinds of soils tested in laboratory is carried out by using the large-scale general finite element software ABAQUS, and the corresponding strength parameters are obtained. the analysis results show that the strength parameters obtained by the numerical simulation are in good agreement with the test. It is proved that the indoor large-scale direct shear test and finite element simulated direct shear test used in this paper can be used as two effective means to measure the strength parameters of construction waste miscellaneous fill. Through the comparative analysis of the strength parameters obtained by numerical simulation, the obtained law is basically consistent with the above laboratory tests. In this paper, the influence of different proportion components on the strength parameters of construction waste miscellaneous fill is discussed, which can be used as a reference for engineering estimation of construction waste miscellaneous fill strength parameters.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU41;X799.1

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