摘要(英) |
ABSTRACT
A computer code based on the element free method to simulate the seepage behavior is developed in this research. Comparisons, specifically on accuracy and efficiency, are made between the newly developed code and the Lagrange finite element program SEEP.
In analyzing unconfined flow problems, remesh is general used in finite element code as is in the SEEP. Besides, construction of the initial element mesh for the input data file is more or less time consuming. Element free method is a meshless numerical technique based on the concept of Moving Least Squares, which interpolates the data of various nodal points within the domain to be analyzed. Shape functions, similar to those in the finite element method, are formed based on a base function and a weight function along with related nodal data for each reference point. Connectivity between nodes and elements is thus freed and saves efforts for the related input.
The influence circle is sometimes obstructed by the boundary due to various geometry of analyzing domain and a rule of determining the nodal influence circle is developed. Gauss integration is used and its result is adjusted while the domain is not perfectly matched by the integration cell. An improved result is obtained by adding nodes on the line of seepage during iteration in simulating the seepage behavior of an earth dam. |
參考文獻 |
參考文獻
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