Study on implicit composite element method for seepage analysis in underground engineering  

作　　者：LI LingZi XIAO Ming 

机构地区：[1]State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University [2]Key Laboratory of Rock Mechanics in Hydraulic Structural Engineering, Wuhan University, Ministry of Education

出　　处：《Science China(Technological Sciences)》2015年第10期1617-1626,共10页中国科学（技术科学英文版）

基　　金：supported by the National Key Basic Research Program of China(Grant No.2015CB057904);the Major Program of the National Natural Science Foundation of China(Grant No.91215301);the National Natural Science Foundation of China(Grant Nos.51279136&51209164);the Research Fund for the Doctoral Program of Higher Education of China(Grant No.20130141110015)

摘　　要：Based on the basic principle of the finite element method, the implicit composite element method for numerical simulation of seepage in underground engineering is proposed. In the simulation, the faults and drainage holes are set implicitly in the model elements without adding additional elements. Elements containing fault or drainage-hole data are termed composite elements. Then, their information data in model could be obtained. By determining the osmotic transmission matrix of the composite elements, the permeability coefficient matrix is then obtained. The method was applied to the numerical simulation of the seepage field around the underground powerhouse of the Ganhe Pumping Station in Yunnan, China, using a compiled three-dimensional finite element method calculation program. The rock mass around the site includes two faults. The seepage field in the rock mass was analyzed at different stages of the engineering project. The results show that, before the excavation of the underground caverns, the rock mass seepage is affected by the faults and the groundwater permeated down along the tangential fault plane. After the excavation of the caverns during the operation period, the groundwater is basically drained away and the underground caverns are mostly above the groundwater level. Thus, the calculation results of the engineering example verify the implicit composite method for the simulation of faults and drainage holes. This method can well meet the calculation demands of practical engineering.

关 键 词：implicit composite element method numerical calculation SEEPAGE underground engineering FAULTS drainage holes finite element method osmotic transmission matrix 

分 类 号：TV223.4[水利工程—水工结构工程]