الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Numerous studies have applied ground survey and remote sensing techniques to monitor beach changes due to the construction of hard structures built along the Nile delta coastline; but, few of these studies have assessed the interaction between these changes and coastal processes prevail (i.e. beach morphodynamics). The broad objective of this research aimed to apply numerical (mathematical) modeling to simulate the impact of major coastal structures on the beach morphologic changes along selected protected coastal sectors at the Nile delta. The study also simulates and evaluates coastal processes and hydrodynamic regime (waves and wave-induced currents, and bed level change) contributed to such changes. Since, understanding the causes of shoreline changes and the coastal processes that effect on the orientation and stability of shorelines are the main pillars that needed for the coherent design of coastal protection engineering structures; therefore, the correct interpretation of shoreline change rate is important to avoid building homes, structures, and infrastructure in high hazard coastal areas. Accordingly, This study succeeded in verifying that using remote sensing technique as a low cost method to export the shoreline vector for all studied localities in the period from (2000-2015) was efficient, since the used satellite images data was calibrated with GPS land surveyed shoreline and quantitative measurements of images used have been done by writing an algorithm code in MATLAB.
2D-modelling by (DHI-Mike21) have been applied along east, west portsaid localities to simulate the beach morphodynamics; the effective waves and currents at east portsaid (El-Tina Plain); El-Gamil breakwaters and at the bay area between Suez Canal jetties and El-Gmail detached breakwater; and at the entrance of Suez Canal to interpret the causes of siltation inside the entrance, which appeared clearly at processed satellite images. Simulation of the effective (significant wave height, and current) have been done for the main four directions (N, NNW, NW, and NE) for Mandara locality, Baltim locality, east and west portsaid localities; beside simulating bed level change for these localities as well. This study also interpreted the causes of sedimentation process inside the Idku ELNG and provided a warning against the risk of constructing any facilities at this region because of the untraditional reverse current trend, which is localized and usually not significant for the northwestern coast of Egypt. Additionally, The present study for shoreline change at Ras El-Bar resort in the period from (2000-2015) show that values of accretion and erosion rates consider as an ideal values for sable beach. Consequently, this locality did not examined hydrodynamiclly by 2D-modelling because there is no need for that, since the message given by the stable beach for a long time is a strong testament refers to the balance of bilateral dimensions within the depths of coastal zone, where as long as beach is stable, the surf zone is stable. The study also evaluated the current situation of Baltim resort detached breakwater and easts Kitchener drain and suggested future protection for the risky places.
ID- LITPACK modeling has been applied along the east and west of Rosetta groins system to calibrate, validate, and predict the future behavior of shoreline till year of 2023 and to evaluate the ate of erosion at the down-drift area of eastern groins, where the national project of fisheries at Gholioun Lake is under constructing; besides evaluating the scouring rate between erosion at the western groins system. Moreover, the area loss and gain from the surface area of beach have been calculated using ARCGIS and the rate of shoreline change along all studied localities have been calculated using DSAS technique.
This research also calculated and examined the bottom hidden erosion in front of the east and west groins system and east and west seawalls in the period from 2002-2015 where, results show that it is continuous with time, and this gives an indication of hazard to evaluate the hydrodynamic regime and the bottom erosion to know the risky places that might exposed to local fall and need continuous protection. Moreover, The analysis of water depth gradation along east and west Rosetta seawalls centerlines for surveyed recorded water depths from bathymetries of year 2002, 2009, 2013, and 2015, and the modeled predicted bathymetry of year 2023 shows that overall Rosetta seawalls are stable except in some places which need more protection to avoid the local fall.
The present research succeeded in evaluating the stability of the Mandara submerged breakwater and highlighting the risk places (opening between breakwaters, bay areas, that exposed to constructive waves and currents, which in turns cause erosion and hinder sailing and swimming at these places.
The study also succeeded in evaluating the erosion process before and after constructing the groin system and evaluation the erosion in front of Rosetta seawalls with recent land surveyed shorelines. Moreover, analysis of surf zone area at Mandara and east and west portsaid localities by profile analysis and modelling calibration has been done.