核废料地质处置概念库HM耦合和THM耦合过程的二维离散元分析与比较  

ANALYSIS AND COMPARISON OF COUPLED HM AND THM PROCESSES BY 2D DISTINCT ELEMENT METHOD IN A CONCEPTUAL NUCLEAR WASTE REPOSITORY

作　　者：张玉军[1] 

机构地区：[1]中国科学院武汉岩土力学研究所,武汉430071

出　　处：《工程力学》2008年第4期218-223,235,共7页Engineering Mechanics

基　　金：国家自然科学基金项目(50578171)

摘　　要：描述了二维离散元程序UDEC4.0中求解热-水-应力耦合问题的主要的理论背景、控制方程和计算原理,并假定一座核废料处置概念库位于具有二组节理且赋存地下水的岩体中,使用UDEC程序对处置库近场分别为水-应力耦合及热-水-应力耦合的过程进行了数值模拟,考察和对比了两种工况下坑道围岩中的位移、主应力、塑性区、温度、节理开度、水压力和流速的分布及温度随时间的变化。结果表明,热-水-应力耦合与水-应力耦合相比,核废料放热使得处置库有水围岩中应力、位移的大小和方向发生明显的变化,并且围岩中节理开度、水压力和水流速度均有所减小,特别是在坑道边墙附近相当显著。若要在裂隙岩体中安全、可靠地设计、建造和运行核废料处置库,进行相关的热-水-应力耦合过程的分析是很重要的。The basic theoretical background, control equations and computation principle for solving thermo-hydro-mechanical （THM） coupling problem in UDEC Version 4.0 of 2D distinct element method are presented. The numerical simulations for the coupled hydro-mechanical （HM） and THM processes in near field of a conceptual disposal repository for nuclear waste are carried out by UDEC assuming the repository to be located a rock mass in which two sets of joint and underground water exist. The investigation is made for the distributions of displacements, principal stresses, plastic zones, temperatures, joint apertures, water pressures, water flow rates and temperature changes with time in the surrounding rock mass of the drift. The results of calculation show： compared with the case of HM coupling, the heat relaxation of nuclear waste in THM coupling makes the obvious changes of magnitudes and directions of the stresses and the displacements in the surrounding rock mass with water of the disposal repository, and causes the decreases of joint apertures, of water pressures and water rates in the rock mass, especially of the middle part of the drift wall. If a disposal repository for nuclear waste in jointed rock mass is intended to be designed, constructed and operated safely and reliably, it is very important to analyze the coupled THM processes concerned.

关 键 词：核废料处置概念库 水-应力耦合 热-水-应力耦合 离散元 数值分析 

分 类 号：TV131[水利工程—水力学及河流动力学]