Application of NEM in seepage analysis with a free surface

As one kind of meshless methods, the natural element method (NEM) constructs shape functions based on the Voronoi diagrams, and it has advantages of both the conventional meshless method and the finite element method. Since the nodes are independent of the integral mesh, it is more suitable for the analysis of seepage with a free surface than the finite element method. In addition, its shape functions satisfy the Kronecker δ conditions, therefore, its boundary conditions can be dealt with much easily than those of such meshless method as element-free Galerkin method (EFGM). In this paper, the NEM was used in the seepage analysis of dams. The initial free surface was assumed first in the calculations, and the location of the free surface was adjusted according to the calculation results. The examples showed that the natural element method lead to satisfactory results.

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