摘要
简述二维离散元程序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。针对美国尤卡山高放射性核废料地质处置坑道规模试验,使用UDEC程序进行热-气-应力耦合过程的数值模拟,分析坑道周边的位移、主应力、节理开度、气压力及气体流速的变化;并将本计算的部分结果和实测数据及国外有限元/有限差分方法的成果进行比较。结果表明,三者温度、应力的分布与变化较为接近,位移分布与LBNL的结果在定性上较为一致,在定量上加热时间短时二者差别较明显,但在同样的数量级内,加热时间长时本计算和LBNL计算所得的位移值与实测结果的接近程度大体相当。从而可以认为使用离散元方法对核废料地质处置中的热-水/气-应力耦合过程进行模拟是可行的。
The basic theoretical background , control equations and computation principle for solving thermo-hydro-mechanical(T-H-M) coupling problem in UDEC(Version 4.0) of 2D discrete element method are presented. Against the coupled T-H-M processes(here 'H'is non-wetting fluid) in near field of drift scale test for geological disposal of high-level radioactive nuclear waste at Yucca Mountain,Nevada,USA,a numerical simulation is carried out by using UDEC. The changes of displacements,principal stresses,joint apertures, non-wetting fluid pressures and flow rates are analyzed. Some calculation results are compared with in-situ measured data and other results obtained by finite element and/or finite difference methods. The following results can be obtained. (1) The distributions and changes of temperatures and stresses are close to each other for the three results. (2) The displacement distributions obtained by UDEC approach qualitatively those of LBNL analysis;and both of them have obvious quantitative differences when heating time is shorter,but the differences are within the same magnitude order. (3) When the heating time is longer,the approaching extents of the measured data of the displacements by UDEC and those by LBNL analysis are match on the whole. So it can be considered that the simulation of coupled T-H-M processes in geological disposal of nuclear waste by discrete element method is practicable.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2007年第S2期3874-3881,共8页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金资助项目(50578171)
关键词
岩石力学
热-水-应力耦合
离散元方法
尤卡山
坑道规模试验
数值模拟
rock mechanics
thermo-hydro-mechanical(T-H-M) coupling
discrete element method
Yucca Mountain
drift scale test
numerical simulation
