الفهرس 
BACKGROUND AND PURPOSEOnly 14 pages are availabe for public view
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Abstract
Earth is subject yearly to almost one million earthquakes; people mostly do not feel either because they are weak or occur in unpopulated areas. Man does not feel the quake usually if its magnitude is up to 4 degrees on Richter scale. The great earthquakes exceed 7 degrees on this scale. When earthquakes dominate the marine waters of the sea by giant waves, violent earthquakes occur where water giant waves called tsunamis.
A tsunami is a huge ocean wave that travels at speeds up to 600 mil / hr (965 km / hr). Sometimes incorrectly called a tidal wave, a tsunami is usually caused by an earthquake, volcanic eruption or coastal landslide. The wave magnitude of tsunami depends on the wavelength (time period), the water depth and the wave height. Tsunami may be initiated after an undersea earthquake.
With urgency in the need for tsunami measures, the idea of utilizing retaining walls that can withstand tsunamis as tsunami shelters is under consideration as part of the evacuation planning for coastal areas where a tsunami would reach shortly in the event of an earthquake. Only limited theoretical studies have been conducted on the impact of tsunami on retaining walls, and little quantitative evaluation has been conducted on the damages caused by tsunami. The current study presents the optimal design of retaining structures against earthquake and tsunami forces. Sliding and overturning stabilities are checked against these forces. Liquefaction effect is totally neglected in all investigated cases.
It is worth mentioning that the current study is limited to static and dynamic loads resulting from earthquakes and tsunamis. Also supporting soil is assumed to be cohesionless.
The main outcome of the current study is that restoration of retaining walls stability against earthquake and tsunami forces is possible using piles. Piles may be included in the original design or be added to the existing walls to ensure proper safety against case III of loading (earthquake and tsunami forces). Also, the study reveals that proper drainage down stream the wall shall release dynamic pore water pressure and thus improve wall stability against both sliding and overturning modes of failure. As for breakwater structure, safety factors could be restored either through adding lateral resistance to the system through piles or creating open slots to release part of tsunami wave water volume.