深埋人工冻结土力学特性试验研究

发布时间：2018-06-29 16:13

  本文选题：人工冻结法 + 含盐量　； 参考：《安徽建筑大学》2014年硕士论文

【摘要】：近年来，随着人工冻结法凿井深度的增加，冻结管断管事故时有发生，主要存在井帮位移大，冻结管断裂，工作面底鼓等问题。目前国内对深土冻土的研究基本以砂土和粉土为研究对象，而本工程杨村矿是钙质粘土，，很少有人对此课题开展研究，其理论方面的研究还有不少空白，为了了解由于冻结管的断裂后导致冻结液的渗漏对周边土层强度的影响。特以淮南杨村矿钙质粘土为研究对象，对淮南杨村煤矿副井井筒的典型土层钙质粘土在低温条件下的力学特性开展实验研究。 （1）通过冻土单轴抗压强度试验，研究淮南杨村矿钙质粘土的冻结强度与温度、含盐量和含水率之间的变化关系。分析了淮南杨村矿钙质粘土在含盐冻结条件下的弹性模量以及泊松比随温度和含盐量的变化规律。 （2）含盐量影响下钙质粘土应力应变关系的建立，通过单轴单轴抗压强度的试验得到应力与应变的关系曲线，通过分析建立以含盐率为影响因子的钙质粘土应力应变关系模型。 （3）通过饱和未含盐与饱和含盐冻冻结土的强度分析，得到了饱和未含盐冻结土强度是饱和含盐之间存在倍数关系，建立了在一定温度下饱和未含盐与含盐冻土强度公式。 （4）以试验为基础，根据正交试验设计，对多种影响下冻土力学性能的因素水平进行试验安排，试验得到了冻土力学性能与多种影响因素的主次关系。 （5）冻土蠕变试验在WDT-100微机控制冻土压力试验机进行，对淮南杨村矿的钙质粘土蠕变特性进行了研究，建立了相应的钙质粘土蠕变模型。 （6）通过蠕变试验，研究了0%、4%、4.5%、5%、5.5%盐分冻结土的蠕变常数A,B,C与温度的变化关系，并比较分析了在-10℃-15℃温度范围内，0%、4%、4.5%、5%、5.5%盐分的蠕变常量A，B,C的变化和盐分之间的关系。
[Abstract]:In recent years, with the increase of the depth of shaft sinking by artificial freezing method, the accidents of freezing pipe break occur from time to time. There are many problems such as the large displacement of shaft side, the fracture of frozen pipe, the bottom drum of working face and so on. At present, the research on deep frozen soil in China basically takes sandy soil and silt as the research object, but the Yangcun mine of this project is calcareous clay, so few people have carried out research on this subject, and there are still many gaps in the theoretical research. In order to understand the influence of the leakage of frozen liquid on the strength of the surrounding soil layer due to the breakage of the frozen pipe. Taking calcareous clay of Yangcun mine in Huainan as the research object, the mechanical properties of calcareous clay in typical soil layer of auxiliary shaft of Huainan Yangcun Coal Mine at low temperature were studied experimentally. (1) uniaxial compressive strength test of frozen soil was carried out. The relationship between freezing strength, temperature, salt content and moisture content of calcareous clay in Yangcun Mine, Huainan is studied. The changes of elastic modulus and Poisson's ratio with temperature and salt content of calcareous clay in Yangcun Mine, Huainan are analyzed. (2) the relationship between stress and strain of calcareous clay affected by salt content is established. The relation curve between stress and strain is obtained by uniaxial compressive strength test. The stress-strain relationship model of calcareous clay with salt content as the influence factor was established by analyzing. (3) the strength analysis of frozen soil without saturated salt and saturated salt was carried out. The relationship between the strength of saturated frozen soil without salt and that of saturated frozen soil is obtained, and the formula of strength of saturated frozen soil without salt and salt at certain temperature is established. (4) based on the experiment and the orthogonal test design, The main and secondary relationships between the mechanical properties of permafrost and various influencing factors are obtained. (5) the creep test of frozen soil is carried out on a WDT-100 microcomputer controlled permafrost pressure tester. The creep characteristics of calcareous clay in Yangcun Mine, Huainan, are studied, and the corresponding creep model of calcareous clay is established. (6) through creep test, the relationship between temperature and creep constant Anb _ (C) of 0.5% salt frozen soil is studied. The relationship between the change of creep constant of 5.5% salt and the salt content is compared and analyzed in the temperature range of -10 鈩

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