پاورپوینت مهندسی سواحل (pptx) 47 اسلاید
دسته بندی : پاورپوینت
نوع فایل : PowerPoint (.pptx) ( قابل ویرایش و آماده پرینت )
تعداد اسلاید: 47 اسلاید
قسمتی از متن PowerPoint (.pptx) :
مهندسی سواحل
اهداف درس
تعاریف، مفاهیم و ترمینولوژی
تاریخچه مهندسی سواحل
رشته های مرتبط با مهندسی سواحل
تعریف ساحل ، اجزا و قلمرو
ساحل به عنوان یک بیوژئومورفولوژیکال سیستم
طبقه بندی سواحل
فرایندهای ساحلی (امواج، جزر و مد، جریانهای دریائی، باد و ...)
بررسی فرایندهای غالب ساحلی (فرسایش، حمل و جابجائی رسوبات ورسوبگذاری)
شناسائی لندفرمهای ساحلی و کاربری آنها
اندازه گیری ، کمی سازی و پیش بینی تغییرات خط ساحلی
راهبردها و راهکارهای حفاظت از سواحل
آشنائی با تجهیزات و ماشین آلات لایروبی سواحل و بندرگاهها
تعریف مهندسی سواحل
علم مطالعه فرایندهای فعال در منطقه ساحلی و اثرات انها بر روی سواحل و سازه های ساحلی و برنامه ریزی برای حفاظت از انها
علوم مرتبط
تاریخچه مهندسی سواحل
الف- مهندسی سواحل در دنیای باستان
The history of coastal engineering reaches back to the ancient world bordering the Mediterranean Sea, the Red Sea, and the Persian Gulf. Coastal engineering, as it relates to harbors, starts with the development of maritime traffic, perhaps before 3500 B.C. Shipping was fundamental to culture and the growth of civilization, and the expansion of navigation and communication in turn drove the practice of coastal engineering. The availability of a large slave labor force during this era meant that docks, breakwaters, and other harbor works were built by hand and often in a grand scale similar to their monumental contemporaries, pyramids, temples, and palaces. Some of the harbor works are still visible today, while others have recently been explored by archaeologists. Most of the grander ancient harbor works disappeared following the fall of the Roman Empire. Earthquakes have buried some of the works; others have been submerged by subsidence, landlocked by silting, or lost through lack of maintenance. Recently, archaeologists, using modern survey techniques, excavations, and old documents, have revealed some of the sophisticated engineering in these old harbors. Technically interesting features have shown up and are now reappearing in modern port designs. Common to most ancient ports was a well-planned and effectively located seawall or breakwater for protection and a quay or mole for loading vessels, features frequently included in modern ports (Quinn 1972).
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Most ancient coastal efforts were directed to port structures, with the exception of a few places where life depended on coastline protection. Venice and its lagoon is one such case. Here, sea defenses (hydraulic and military) were necessary for the survival of the narrow coastal strips, and impressive shore protection works built by the Venetians are still admired. Very few written reports on the ancient design and construction of coastal structures have survived. A classic treatise by Vitruvius (27 B.C.) relating the Roman engineering experience, has survived (Pollio, Rowland, and Howe 1999). Greek and Latin literature by Herodotus, Josephs, Suetonius, Pliny, Appian, Polibus, Strabo, and others provide limited descriptions of the ancient coastal works. They show the ancients' ability to understand and handle various complex physical phenomena with limited empirical data and simple computational tools. They understood such phenomena as the Mediterranean currents and wind patterns and the wind-wave cause-effect link. The Romans are credited with first introducing wind roses (Franco 1996).
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ب- مهندسی سواحل قبل از دوره رومیان
Most ancient coastal efforts were directed to port structures, with the exception of a few places where life depended on coastline protection. Venice and its lagoon is one such case. Here, sea defenses (hydraulic and military) were necessary for the survival of the narrow coastal strips, and impressive shore protection works built by the Venetians are still admired. Very few written reports on the ancient design and construction of coastal structures have survived. A classic treatise by Vitruvius (27 B.C.) relating the Roman engineering experience, has survived (Pollio, Rowland, and Howe 1999). Greek and Latin literature by Herodotus, Josephs, Suetonius, Pliny, Appian, Polibus, Strabo, and others provide limited descriptions of the ancient coastal works. They show the ancients' ability to understand and handle various complex physical phenomena with limited empirical data and simple computational tools. They understood such phenomena as the Mediterranean currents and wind patterns and the wind-wave cause-effect link. The Romans are credited with first introducing wind roses (Franco 1996).
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The earliest were rock cut, in that natural features like offshore reefs were adapted to give shelter to craft riding at anchor.
b. In the second group, vertical walls were built on convenient shallows to serve as breakwaters and moles. Harbors of this type were in protected bays, and often the walls connected with the defenses of a walled town (for example, ancient Tyre on the Lebanese coast). Often these basins were closeable to traffic using chains to prevent the entry of enemy ships (Franco 1996).
c. The third group were harbors that were imposed on even unpromising coasts by use of Roman
innovations such as the arch and improved hydraulic cement. Projects like this required the engineering, construction, and financing resources of a major empire.
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All ancient ports had one thing in common: they had to be kept clear of silt at a time when mechanical dredging was unknown. This was accomplished by various means. One was by designing the outer parts of the harbor so that they deflected silt-bearing currents. The second was by allowing a controlled current to flow through the port or by flushing it out when necessary by means of channels. For example, at Sidon, a series of tanks (like swimming pools) were cut into the harbor side of a natural rock reef. The tanks filled with clear water that was held in place with sluice gates. When the gates were opened, currents of clear water would flush the inner harbor. Documentary and archaeological evidence show that both Tyre and Sidon were flourishing and powerful ports from the Bronze Age through the Roman era and must therefore have been kept clear of silt for over a thousand years (Frost 1963). Another method of preventing silt consisted of diverting rivers through canals so that during part or much of the year, the flow would enter the sea at location well away from the harbor.
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