A Study on The Use of Semi-Open Groin System for Protecting The North-West Coast of Egypt Along The Mediterranean Sea

摘要

This paper presents groins with a clear opening in their cross section asa tool for protecting the shore area. The opening allows watercirculation and flushing in the near shore zone while protecting theswimmers from direct exposure to wave attack. The possible impact ofthe opening size and the internal properties of the groin on the shoreline changes and water circulation have been investigated. Thedominant wave/current conditions along the North-West coast of Egypthave been considered for various possible configurations of the semiopengroin to identify the appropriate design. Wind and wave data ofAl-Daba Meteorological Station (DMS) have been adopted for theperiod 2000-2005. Attention has been given to the EgyptianEnvironmental Law 4/1994 and bathymetric survey of the bed contourshas been prepared for Ras Al-Daba zone in the North-West coast ofEgypt. A numerical model, namely known as Surface water ModelingSystem (SMS) ver.10, has been adopted in the simulation. The resultsof the model have been presented in convenient graphical formats andanalyzed to select the appropriate configuration of the semi-open groinsuitable. The results and analysis provide general guidelines for the useof semi-open groins in coastal resorts that can be applied to wide rangeof wave climate. It has also been found that semi-open groins can be ofgood help to provide safe swimming conditions with minimum impacton the shoreline if groins were properly studied. Wide gap spacing andpermeable groins generally reduce the shoreline changes.