الفهرس Only 14 pages are availabe for public view
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Abstract
A Finite element study of seepage flow under floor of hydraulic
structure floor with cracks and cracked sheet piles was conducted using
four-node quadrilateral isoparametric element. An experimental work
was performed using Sand Model Tank. A dimensional analysis was
done to obtain the dimensionless parameters affecting the seepage flow
characteristics. Single sheet pile, double sheet piles, single crack and
double cracks were studied. The effect of the depth of impermeable
layer, relative depths of sheet pile(s), the position of crack(s) in sheet
pile(s) and in the floor were presented using dimensionless graphs.
Application of the seepage model, using finite element method, was
introduced on the floor of Esna Barrages using four-node quadrilateral
isoparametric element. The effect of possible cracks in the floor and in
sheet piles were studied and the factor of safety in the uplift pressures
and exit gradients were obtained. It was found that the maximum
reduction in the relative uplift pressure occurred due to an increase in the
relative depth of crack which ranged from 0.2 to 0.4 measured from
floor. The presence of sheet pile wall causes a significant reduction in
the relative uplift pressures and the presence of cracks in the sheet pile
increased the relative uplift pressure under the floor part downstream the
sheet pile. The increase in the relative crack depth in the sheet pile
measured from the floor caused an increase in the relative uplift
pressures under the floor upstream the sheet pile. But for the floor
downstream the sheet pile, the relative uplift pressures was decreased for
the increase in the relative depth of crack.