高地温水工高压隧洞的结构模型试验相似材料研究

发布时间：2018-03-13 01:32

  本文选题：高地温　切入点：水工高压隧洞　出处：《广西大学》2014年硕士论文　论文类型：学位论文

【摘要】：本文依托国家自然科学基金资助项目：高地温梯度水工高压隧洞THM耦合作用下的承载特性研究(项目编号：51369007),针对高地温水工高压隧洞结构模型试验相似材料研究稀少的问题,根据高地温水工高压隧洞的受力特征,运用结构模型试验的相似理论,进行了结构模型相似材料的研制。本文采用水泥、砂、碎石、重晶石粉等原材料,通过配比试验,制备出一种热稳定性好、便于施工、力学性能参数稳定且可调范围广的新型地质力学模型相似材料,弥补了高地温高压水工隧洞模型相似材料研究的空缺。通过力学性能测试、热线膨胀系数测试得到相似材料的物理参数数据,分析得出原材料含量对试验测量的材料力学性能参数的影响规律,并将试验测量的相似材料物理参数赋值于结构模型试验的数值仿真模型,进行高地温水工高压隧洞模型的仿真模拟,分析了高地温高压水工隧洞模型的受力特征、破坏形态,为结构模型试验提供参考依据。本文主要研究成果如下：(1)组织了相似材料配比试验,并进行抗压强度、抗拉强度、弹性模量了力学性能测试,与原型岩体物理参数进行比较后,确定了两组配比作为模型试验相似材料,分别符合模型试验Ⅱ类围岩、Ⅲ类围岩要求。通过综合分析相似材料中不同含量的水泥、石子、重晶石粉、水胶比等与相似材料力学性能参数测试结果之间的关系,得到原材料含量不同对材料抗拉强度、抗压强度、弹性模量的影响规律：相似材料的水泥含量、重晶石粉含量、石子含量的增大,以及水胶比的减小,都会导致抗拉强度、抗压强度、弹性模量的增大。(2)通过进行热线膨胀系数的试验,测得选定相似材料的热膨胀系数符合一般岩石的热线膨胀系数的取值范围,满足相似材料要求。(3)通过结构模型试验模拟得到以下仿真模拟结果：高地温高压水工隧洞结构模型试验,在充水时,围岩与隧洞中的水发生热对流,产生温度梯度,围岩受温度拉应力作用明显,围岩承载能力比一般高压水工隧洞模型低,温度效应不容忽视；高地温高压水工隧洞结构模型受到温度场、渗流场、应力场的耦合作用,受力情况复杂,选择T-H-M耦合模型进行计算可能更加合理,在T-H-M耦合作用下,围岩形成发散型裂缝并有少数裂缝深入发展,出现水力劈裂现象。
[Abstract]:In this paper, based on the project supported by National Natural Science Foundation: research on bearing characteristics of high geothermal gradient hydraulic and high pressure tunnel under THM coupling (Project No.: 51369007), the similar materials for structural model test of highland warm hydraulic tunnel are seldom studied. According to the stress characteristics of high temperature and high pressure tunnel and the similarity theory of structural model test, the similar material of structural model is developed. The raw materials such as cement, sand, crushed stone, barite powder and other raw materials are used in this paper. A new type of similar material with good thermal stability, easy construction, stable mechanical property parameters and wide adjustable range of geomechanical model was prepared, which made up for the lack of research on the similar material of high temperature and high pressure hydraulic tunnel model. The physical parameters of the similar materials were obtained by the thermal linear expansion coefficient test, and the influence of the content of raw materials on the mechanical properties of the materials measured in the experiment was analyzed. The physical parameters of similar materials measured in the experiment are assigned to the numerical simulation model of the structural model test, and the simulation simulation of the highland temperature and high pressure tunnel model is carried out, and the mechanical characteristics and failure patterns of the high temperature and high pressure hydraulic tunnel model are analyzed. The main research results of this paper are as follows: (1) the similar material ratio tests are organized, and the compressive strength, tensile strength and elastic modulus are tested, and compared with the physical parameters of the prototype rock mass. Two groups of similar materials are determined as model test materials, which meet the requirements of model test type 鈪，

本文编号：1604251