Enhanced Saturated Seepage Analysis Using Fractal Hydraulic Conductivity (Case Study: Gale Chay Dam)

Abstract

AbstractThe seepage analysis of an earth-fill dam is of prime importance in its stability and design. The accurate estimation of the permeability and the hydraulic conductivity of the material used in the dam core is highly influential on the estimated seepage. In this research, the Gale chay dam was chosen for the seepage analysis, and the dam is located in the northwest of Iran in East Azerbaijan province. The fractal theory was employed to study the porous structure of the core material and approximate the corresponding permeability hydraulic conductivity. For this purpose, the dam core material was gathered and analyzed using the Scanning Electron Microscope (SEM) and the image processing technique. The steady-state seepage analyses were conducted by the Finite Element Model (FEM) using the estimated fractal hydraulic conductivity, as well as the minimum and maximum hydraulic conductivities within the measured range indicated by the laboratory experiment. Providing a relative error of 12%, the estimated fractal hydraulic conductivity enhanced the seepage analysis by almost 70% compared to the result of maximum hydraulic conductivity. Also, the implication of fractal hydraulic conductivity resulted in a better seepage analysis in terms of safety factors compared to the estimated seepage by the minimum hydraulic conductivity. The mentioned results signify the influence of a more precise observation of the soil structure using the fractal theory. KeywordsSeepage analysisFinite Element Model (FEM)Saturated hydraulic conductivityScanning Electron Microscope (SEM)FractalGale chay dam