ZHANG Shunfu and DING Liuqian

China Institute of Water Resources and Hydro Power Research, Beijing 100038, China; Research Center on Flood & Drought Disaster Reduction of the Ministry of Water Resources, Beijing 100038, China

Abstract: To solve the “line-style structure” problem often encountered in unconfined steady seepage analysis, Composite Grid Method is adopted. Two sets of independent grids are used in numerical simulation. One is the coarse grid of larger size simulating the entire region without consideration of “line-style structure” and the other is the fine grid of relatively small size simulating the domain including the “line-style structure”. Adjustments are carried out iteratively between the coarse grid and fine grid until desired convergence precision is achieved. With Composite Grid Method, the amount of discretization is greatly reduced. The Composite Grid Method can be adapted to non-regular grid. Numerical simulation result shows that the theory is reasonable and the program is reliable. Composite Grid Method provides an approach to solving the “line-style structure” problem in unconfined steady seepage analysis.

Key words: unconfined steady seepage; Composite Grid Method; line-style structure; improved Initial Flow method; Finite element method

Published in: Journal of China Institute of Water Resources and Hydropower Research, No. 1, 2016