Abstract
The cross section of fill dams is generally triangular or trapezoidal in shape. If the analytical system contains such geometry, the finite difference or finite element procedure is the most effective for analyzing such problems for handling the boundary condition. However, it is inevitable that the computational efforts need to be increased for obtaining more precise solutions using these procedures. For that reason, a more simplified analytical method is proposed in this paper. It is characteristic to sum the finite difference equation of a given equation under boudary conditions. Basically, this approach is similar to the procedure from which the closed-form analytical solution is derived, whereas, solutions obtained are reduced to a discrete function. Applying this method to a two-dimensional probrem of seepage, the flow net in the impervious dam sections can be computed. To ascertain the validity of this method, the forward finite difference metod is employed here. It is indicated that the computational results by this procedure agree with the one by the conventional finite difference method with a reasonable degree of accuracy in the case of the impervious zone section and the homogeneous type of dam with isotropic and anisotropic conditions. In addition, the determination of phreatic lines is also proposed by fitting a power function of a third-order equation.
