人工冻土地基温度场模型试验及特性分析

发布时间：2018-05-10 15:10

  本文选题：人工冻土 + 温度场　； 参考：《安徽理工大学》2017年硕士论文

【摘要】：经济的迅速发展带动能源的发展,各种大型矿物能源相继被开发利用,因此需要建设工程项目越来越多。在工程建设的过程中,各种工程问题不断出现,其中由于冻土存在的工程隐患最为严重。而我国的冻土占国土面积比较多,因此对冻土性质的研究具有十分重要的意义。土体冻结,温度发生变化的过程中,性质也会相应改变。影响土体温度的众多热物理参数中,导热系数的影响尤为重要。本文采用安徽理工大学自主研发人工冻土冻结试验平台进行室内模型试验,模拟冻土冻结温度的变化,模型试验的冻结管分左右两个圈径,分别在下(-0.6m)、中(-0.3 m)、上(-0.1m)三层进行温度实时检测;对支持向量机理论进行阐述,在此理论的基础上,利用支持向量机对采集到的数据进行预测,预测温度的变化;利用大型有限元分析软件ANSYS,建立人工冻土冻结温度场模型,对不同导热系数条件下的冻土进行模拟;在导热系数反分析理论的基础上,利用最小二乘法准则对ANSYS后处理得到的测温点理论温度数据和试验测得的温度数据进行分析,在模拟的导热系数范围内确定出一个最优导热系数;利用得到的最优导热系数进行模拟,通过对比模拟得到的温度和实测温度,验证反分析得到的等效导热系数的准确性,本模型试验反分析得到的等效导热系数为1.875kJ/(m·h·℃)。本文先是利用室内模型试验模拟冻土冻结过程,利用支持向量机对温度进行实时预测,可以有效及时预测冻土温度变化;并利用大型有限元软件进行导热系数反演,得到的模拟温度曲线与实测温度曲线吻合较好,对实际的工程中冻土研究有很好的参考价值。
[Abstract]:With the rapid development of economy and the development of energy, a variety of large-scale mineral energy has been developed and used, so more and more construction projects are needed. In the process of engineering construction, various engineering problems appear constantly, among which the engineering hidden danger caused by frozen soil is the most serious. The permafrost occupies more land area in China, so the study of permafrost properties is of great significance. In the process of soil freezing and temperature changing, the properties will change accordingly. Among the many thermophysical parameters affecting soil temperature, the influence of thermal conductivity is particularly important. In this paper, the artificial frozen soil freezing test platform developed by Anhui University of Technology is used to carry out indoor model test, simulating the change of freezing temperature of frozen soil. The freezing pipe of the model test is divided into two circles diameter. The theory of support vector machine (SVM) is expounded on the basis of which the data collected are forecasted by support vector machine (SVM) to predict the change of temperature. In this paper, the model of freezing temperature field of artificial frozen soil is established by using the finite element analysis software ANSYS, and the frozen soil under different thermal conductivity is simulated, and based on the theory of back analysis of thermal conductivity, the model of freezing temperature field of artificial frozen soil is established. The theoretical temperature data obtained from ANSYS post-processing and the experimental temperature data are analyzed by using the least square method, and an optimal thermal conductivity is determined in the range of simulated thermal conductivity. By comparing the simulated temperature with the measured temperature, the accuracy of the equivalent thermal conductivity obtained by the back analysis is verified. The equivalent thermal conductivity obtained by the back analysis of the model test is 1.875kJ/(m h 鈩，

本文编号：1869804