NUMERICAL PARAMETRIC SIMULATIONS FOR SEEPAGE FLOW BEHAVIOUR THROUGH AN EARTHFILL DAM
DOI:
https://doi.org/10.11113/mjce.v14.15643Abstract
A finite element method is practical and applicable for many fields including for
geotechnical engineering structures. Seepage through earth dam is difficult to
analyse especially dams with multiple zones. Therefore, finite element is the best
tool for analyzing seepage flow in an earthfill dam. The main objective of the
project is to simulate the seepage flow through an earthfill dam. Three sets of
steady state numerical modeling are presented in the paper. Two sets of
parametric studies on long-term steady state flow were conducted using
homogeneous and zoned earthfill dams for studying the behaviour of seepage in
the dams. The third set of the simulations is a case study, which is analysis of
steady state seepage condition for Kuala Yong Dam, the main part of Pergau
Hydroelectric Project, Tenaga Nasional Berhad (TNB). The seepage quantity at
the core and the downstream section were determined for the steady state flow
condition. The results of the parametric simulations show that the total fluxes at
downstream changes with the coefficient of permeability value. The flux quantity
changes linearly with maximum seepage velocity. Significant differences can be
observed in the case study, for the analysis using the coefficient of permeability
function (varies with matric suction) versus analysis using a constant coefficient
of permeability. Relationship between flux quantity at downstream and
maximum seepage velocity is non-linear when hydraulic conductivity function is
introduced in seepage analysis.
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