A STUDY ON METHOD OF FRAGMENTS FOR SEEPAGE ANALYSIS UNDER HYDRAULIC STRUCTURE

Abstract

The techniques in the investigation of problem of flow of subsoil water below hydraulic structure are commonly employed for the solution of Laplace's equation. The technique consists of: 1. Graphical method 2. Hydraulic models 3. Electrical analogy models 4. Analytical method. The analytical method aims at the solution of Laplace's equation mathematically by Conformal Mapping transformation. In this method the parameters of transformation are obtained from the boundary conditions. An approximate analytical method of solution for any confined flow system with finite depth of porous medium, directly applicable to design, known as "METHOD OF FRAGMENTS" has been suggested by Pavlovsky, vide Harr, 1962 to solve the computation of seepage under weir with multiple pilling. The fundamental assumption of method of fragment is that equipotential lines at various critical parts of flow region can be approximated by straight vertical lines that divide the region into section or fragment. The accuracy of method of fragment depends on the shape of seepage region involved in the manner of fragmentation. Many of the practical working formulae available in the literature are worked out by the Method of Fragment....