【作者】 刘伟；

【导师】 毕继红；

【作者基本信息】 天津大学 ， 结构工程， 2006， 硕士

【摘要】 流固耦合与热流固耦合问题是当前岩土力学和流体力学研究的热点课题,也是多学科交叉性质的前沿研究课题。随着我国交通事业的发展,越来越多的隧道建设在高地应力、高地温、富含地下水的区段,给隧道的设计、施工带来很大的难度,同时施工安全也存在很大隐患。而在目前对隧道开挖的数值模拟分析方法中,综合考虑这些因素的很少。本文采用宏观连续介质方法,将实际的多孔介质视为一种理想的连续介质,系统地分析流、固、热三场之间的耦合关系、三场耦合的力学机理以及结合点。将有效应力原理运用到适合变温条件下地下水的渗流情况,并在此基础上建立了岩石变形耦合方程。对于温度场的耦合,通过虚位移原理将变化的温度场产生的热应力转化为“热荷载”加载到岩石固相骨架上。并以位移变量u、v、w和孔隙压力变量p为基本变量,把变化的温度场产生的热应变转化为“热荷载”加于结点上。运用等参元、加权残数法、高斯积分法等推导平面八结点单元的耦合方程以及刚度矩阵中各元素的计算方法。在模拟中采用多层耦合应力超前解除法,并运用ABAQUS有限元分析软件对实例工程进行了流固耦合模拟(包括排水和不排水两种情形)、热流固耦合模拟(包括排水和不排水两种情形)、总应力分析,通过与实测数据进行比较对照,详细分析了洞室拱顶沉降、边墙收敛、渗水压力等,找出对地下工程最适合的模拟方法。更多还原

【Abstract】 Fluid-Solid coupling and Thermal-Fluid-Solid coupling are hotspot problems of rock and soil mechanics and hydromechanics, are multi-disciplinary and crossed forward problems. With the development of traffic projects, more and more tunnels are constructed on zone of high stress, high earth temperature and groundwater. But now all methods of numerical simulation on tunnel excavation don’t consider those factors comprehensively.We establish Thermal-Fluid-Solid coupled equation applying continuous medium method and consider groundwater infiltration and temperature change fully. We translate thermal stress that generate from temperature change into thermal load, and apply this load to solid phase. We consider u, v, w, and water pressure p as basic variable and apply thermal load that generate from temperature change to finite element node.Based on ABAQUS program, 2-D finite element analysis model is established to simulate the tunnel excavation. Fluid-Solid coupling and Thermal-Fluid-Solid coupling models are created to simulate groundwater infiltration and temperature change. Some conclusions are summarized through contrasting measure data with analysis date to provide corresponding guidance for subsequent project.更多还原