الفهرس 
chapter 1Only 14 pages are availabe for public view
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Abstract
Egypt is potentially one of the most countries at risk from the effects of
climatic changes. Sea-level rise is the most fundamental challenge of global
warming. If this occurred, coastal cities, ports, and wetlands would be threatened with severe frequent inundation, increasing beach erosion, and saltwater encroachment into coastal aquifers. Without serious protection and adaptation measures, millions of peoples will be displaced from their homes and will lose their jobs.
The purpose of this research is to present one possible mitigation system
compnsmg the use of a PVC sheet pile wall embedded into an underground
impervious cut-off wall, as a two-component system, to protect the northern seashores of Egypt from the inundation, as well I imiting the infiltration of seawater into the sand aquifer along the Egyptian coasts.
A supplementary experimental study was performed to develop mix, as a
construction material, for a cut-off wall containing sand, silt, bentonite, and cement by-pass dust. The properties of the mix which perform the minimum permeability in the experimental study was used in a 2-D finite element model, using Z-Soil finite elements program, to Study the main factors which affect the head losses through that cut-off wall to arrive to the optimum dimensions. In case of a l-rn rise
in the sea level, the numerical model represented the proposed solution with its two-component protection. The proposed solution succeeded in providing a top barrier wall in addition to complete blockage of the subsurface seeping water.
The result of the experimental study showed that the minimum permeability
was achieved for a mixture of 10% CBPD, 15% bentonite, 15% silt, and 85% sand
by weight of the native soil which represented in the laboratory program by the weight of (sand and silt). The permeability value obtained using this mix was in the order of 10-6 cm/sec. The results also indicated that the UCS of the CBPB mix is inversely proportional with the increase of silt. Also the UCS of the mix increased
with increasing the bentonite content, while the UCS increased by 400% as the
CBPD content is increased by 20%.