Abstract:
Embankment dam failure may occur due to different reasons such as structural
instability conditions, hydraulic conditions, seepage through the dam body and
foundation. The determination of factor of safety for the dam slope stability, under
different cases of operations, is vital to ascertain the dam overall safety. In this
thesis, Finite Element modeling is employed for simulating seepage and slope
stability analysis of earth dam problems via GeoStudio software. The model is
verified, and then it is employed to analyze seepage and stability of Grindeho
Dam. Three different cases of operation are considered; end of construction
before filling the reservoir, steady state seepage and rapid drawdown of the
reservoir. Four major analytical methods there used to assess the stability of the
dam side slopes; Morgenstern-Price, Bishop, Janbu, and Spencer. Benchmark
safety regulation criteria (United State army of Corps Engineers and British dam
society) are obeyed. Additionally slope stability determined by simple/manually
calculation by simplified Bishop Method; finally the result was compared with
slope/w software result. The results of the analysis presented in this paper
confirm the safety of Grindeho dam against combined seepage and slope stability
under all cases of operation. The result of stability analysis performed showed
that all parts of the dam are safe within the prescribed rang of factors of safety for
the possible all loading and operation cases. But all the critical slip surfaces pass
through the dam shell which indicates that this zone represents the weaker zone
and it needs spatial attention.
