الفهرس 
EXPERIMENTAL MODELOnly 14 pages are availabe for public view
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Abstract
Seepage from canals is a vital subject of the engineer. In unlined canal systems so much water is often lost due to seepage. In several systems, the quantity of water delivered to the fields may be less than half of that drawn in the head. The present work is intended to study the problem of seepage from canals with compound sections in which water surface rises above the berm level. Seepage rates increase in a canal with compound section compared to a traditional canal with simple section. This is due to two reasons; first, the increase of head difference between water surface in the canal and the groundwater table. Secondly, is the increase in wetted perimeter length and consequently in seepage area. This may lead to a considerable loss of water and low conveyance efficiency. Seepage from canals is a dynamic process that is complicated by a variety of factors. The variables considered in the present study are: the flow water depth, the drawdown depth of groundwater table below canal water surface, soil permeability, the depth of the permeable layer, the width of the berm, and the side slopes. The obtained results were analyzed as dimensionless curves. This study scrutinizes many of research investigations and their findings reported in published literatures. An experimental investigation had been conducted using the viscous flow (Hele-Shaw) model to obtain the quantity of seepage and to locate the shape and location of the phreatic surface. A computer program based on the Finite Element Method was used to the same purpose. The four cases considered in the present study are.