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صفحه 2:
اهداف درس
تعاریف» مفاهیم و ترمینولوژی
تاریخچه مهندسی سواحل
رشته های مرتبط با مهنسی سواحل
تعریف ساحل ۰ اجزا و قلمرو
ساحل به عنوان یک بیوژئومورفولوژیکال سیستم
طبقه بندی سواحل
فرایندهای ساحلی (امواج» جزر و مد» جریانهای دریانی» باد و ...)
بررسی فرایندهای غالب ساحلی (فرسایش» حمل و جایجانی رسوبات ورسوبگذاری)
شناسانی لندفرمهای ساحلی و کاربری آنها
اندازه گیری ۰ کمی سازی و پیش بینی تغییرات خط ساحلی
راهبردها و راهکارهای حفاظت از سواحل
آشنائی با تجهیزات و ماشین آلات لایروبی سواحل و بندرگاهها
صفحه 3:
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
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الف- مهندسی سواحل در دنیای باستان
he 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)
صفحه 8:
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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The origins of breakwaters are unknown. The ancient Egyptians built boat basins
with breakwaters on the Nile River at Zoser's (Djoser) step pyramid (ca. 2500 B.C.)
(Inman 2001). The Minoans constructed a breakwater at Nirou Khani on Crete long
before the explosion of Santorini (Thera) in ca. 1500 B.C. The breakwater was
small and constructed of material taken from nearby dune rock quarries (Inman
1974, Figure 4). In the Mediterranean, size and sophistication of breakwaters
increased over time as the Egyptian, Phoenician, Greco-Macedonian, and Roman
civilizations developed and evolved. Breakwaters were built in China but generally
at a later date than in the Mediterranean. Probably the most sophisticated man-
made harbor of this era was the first harbor of Alexandria, Egypt, built
west of Pharos Island about 1800 B.C. by the Minoans. The main basin, built to
accommodate 400 ships about 35 m in length, was 2,300 m long, 300 m wide and
6-10 m deep. Large stone blocks were used in the many breakwaters and docks in
the harbor. Alexander the Great and his Greek successors rebuilt the harbor (300-
100 B.C.) in monumental scale. The Island of Pharos was joined to the mainland by
a 1.5 km breakwater with two openings dividing two basins with an area of 368
hectares (910 acres) and 15 km of quay front. Alexandria is probably best known
for the 130m-high lighthouse tower used to guide ships on a featureless coast to
the port from 50 km at sea. The multi-storied building was built with solid blocks of
stone cemented together with melted lead and lined with white stone slabs.
Considered one of the Wonders of the
Ancient World, it eventually collapsed due to earthquakes between 1326 and 1349
(Franco 1996, Empereur 1997).
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Another feature of the Greek harbors was the ee of colossal statues to
33 اس Jossat-statues-of King Re y-which-steed-atth
base of the lighthouse, have been found with the lighthouse debris.
Historians report the most famous harbor statue was the 30 m high
Colossus of Rhodes, which stood on the breakwater heads. Three ancient
windmill towers are still surviving upon the Rhodes breakwater (Franco
1996). Frost (1963) notes that the Greeks had used hydraulic cement
long before the Romans.
چ- مهندسی سواحل در رم باستان
The Romans introduced many revolutionary innovations in harbor
design. They learned to build walls underwater and constructed solid
breakwaters to protect exposed harbors. They used metal joints and
clamps to fasten neighboring blocks together and are often credited with
discovering hydraulic cement made with pozzolanic ash obtained from
the volcanic region near Naples, which hardens underwater. Frost (1963)
notes that the Greeks had used hydraulic cement long before the
Romans. The Romans replaced many of the Greek rubble mound
breakwaters with vertical and composite concrete walls
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The Romans introduced many revolutionary innovations in harbor
design. They learned to build walls underwater and constructed solid
kwaters-te-pretect expesed-harbersTh: d-metatjeints- and
clamps to fasten neighboring blocks together and are often credited with
discovering hydraulic cement made with pozzolanic ash obtained from
the volcanic region near Naples, which hardens underwater. Frost (1963)
notes that the Greeks had used hydraulic cement long before the
Romans. The Romans replaced many of the Greek rubble mound
breakwaters with vertical and composite concrete walls . These
monolithic coastal structures could be built rapidly and required little
maintenance. In In most cases, rubble or large stone slabs were placed in
front of the walls to protect
against toe scour. The Romans developed cranes and pile drivers and
used them extensively in their construction. This technology also led
them to develop dredges. Another advanced technique used for deep-
water applications was the watertight floating cellular caisson, precursor
of the modern day monolithic breakwater. some cases wave reflection
may have been used to prevent silting. They also used low, water-
surface breakwaters to trip the waves before they reached the main
breakwater. The peculiar feature of the vertical wall breakwater at
Thapsus (Rass Dimas, Tunisia) was the presence of vents through the
wall to reduce wave impact forces. This idea is used today in the
construction of perforated caisson breakwaters (Franco 1996). Using
صفحه 13:
The Romans introduced many revolutionary innovations in harbor
design. They learned to build walls underwater and constructed solid
kwaters-te-pretect expesed harbers-They-used metal joints and
clamps to fasten neighboring blocks together and are often credited with
discovering hydraulic cement made with pozzolanic ash obtained from
the volcanic region near Naples, which hardens underwater. Frost (1963)
notes that the Greeks had used hydraulic cement long before the
Romans. The Romans replaced many of the Greek rubble mound
breakwaters with vertical and composite concrete walls . These
monolithic coastal structures could be built rapidly and required little
maintenance. In In most cases, rubble or large stone slabs were placed in
front of the walls to protect
against toe scour. The Romans developed cranes and pile drivers and
used them extensively in their construction. This technology also led
them to develop dredges. Another advanced technique used for deep-
water applications was the watertight floating cellular caisson, precursor
of the modern day monolithic breakwater. some cases wave reflection
may have been used to prevent silting. They also used low, water-
surface breakwaters to trip the waves before they reached the main
breakwater. The peculiar feature of the vertical wall breakwater at
Thapsus (Rass Dimas, Tunisia) was the presence of vents through the
wall to reduce wave impact forces. This idea is used today in the
construction of perforated caisson breakwaters (Franco 1996). Using
صفحه 14:
The southwestern breakwater at Caesarea contained a “forebreakwater"
that acd as a submerged reef that ۳ the wave = Go tsing it to break
2001). The largest manmade harbor 0 was the 1 port of
Rome; the maritime town at the mouth of the Tiber River was named
Portus (The Port). It is now some four km from the sea, partly buried
under Rome-Fiumicino airport. Despite its importance to the capital of
the empire, (300,000 tons/year of wheat from Egypt and France), the
harbor always suffered siltation from the river. Trajan, who also built the
ports of Terracina and Centumcellae, built Portus' inner hexagonal basin.
The port of Centumcellae was built just to serve his villa at a site with
favorable rocky morphology. A grandiose engineering project between
107-106 B.C. created a sheltered bathing and boating retreat. Slaves
from all parts of the empire excavated a harbor and hauled in massive
stones to create an artificial harbor to dampen the force of the waves.
After the decline of Portus, it became, and remains, the Port of Rome.
After remaining unchanged for over 1,000 years, the inner Roman Basin,
which was dredged from rock (200,000 m3 or 260,000 yd3), is still in
use. Roman engineers also constructed harbors in northern Europe along
the main waterways of the Rhine and Danube and in Lake Geneva. They
became the first dredgers in the Netherlands to maintain the harbor at
Velsen. Silting problems here were solved when the previously sealed
solid piers were replaced with new “open"- piled jetties. In general, the
Romans spread ale ی ۳ لك ای OL the western world. nel
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They developed and properly used a variety of design concepts and
construction techniques at different coastal cites to suit the local
hydraulic and morphological conditions and available materials (Franco
1996). The Romans also introduced to the world the concept of the
holiday at the coast. The ingredients for beach holidays were in place:
high population density coupled with a relatively high standard of living,
a well-
established economic and social elite, and a superb infrastructure of
roads. From the end of the republic to the middle of the second century
of the empire, resorts thrived along the shores of Latium and Capania,
and an unbroken string of villas extended along the coast from the
seashore near Rome to the white cliffs of Terracina. Fine roads
connected these resorts to the capital, allowing both the upper crust and
the masses to descend from sultry and vapor-ridden Rome to the sea.
For five hundred years, the sybaritic town of Baiae reigned as the
greatest fashionable beach resort of the ancient world. Seneca the
Younger called Baiae a (Lencek and Bosker 1998).
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After the fall of the Western Roman Empire, a long hiatus in coastal
technology and engineering prevailed throughout most of the European
world with a few exceptions. Little is recorded on civil engineering
achievements during the Dark and Middle Ages. The threat of attack
from the sea caused many coastal towns and their harbors to be
abandoned. Many harbors were lost due to natural causes such as rapid
silting, shoreline advance or retreat, etc. The Venice lagoon was one of
the few populated coastal areas with continuous prosperity and
development where written reports document the evolution of coastal
protection works, ranging from the use of wicker faggots to reinforce the
dunes to timber piles and stones, often combined in a sort of crib work.
Protection from the sea was so vital to the Venetians, that laws from
1282 to 1339 did not allow anyone to cut or burn trees from coastal
woods, pick out mussels from the rock
revetments, let cattle upon the dikes, remove sand or vegetation from
the beaches or dunes, or export materials used for shore protection
(Franco 1996). Of necessity, Byzantium had become a sea power,
sending forth fleets of merchant ships and multi-oared dromonds (swift
war vessels) throughout the Black Sea and Mediterranean. When the
weary soldiers of the first crusades reached Byzantium's capital city,
Constantinople, in 1097, they were amazed and awed by its
magnificence, sophistication, and scientific achievements.
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recognized the 0۵۳۱96۲ 01 ۱۱۵۵005 ۵۱۱۵0 560 inundation OF low-lying lands.
On the Medway, for example, embankments built by the Romans as sea
defense remained in use until the 18th century (Palmer and Tritton
alluvial material, were exceeding fertile but were also vulnerable to
flooding from both runoff and storm surges. In the Middle Ages, the
Church became instrumental in reclaiming and protecting many
marshes, and monks reclaimed portions of the Fylde and Humber
estuaries. In 1225, Henry Ill constituted by Charter a body of persons to
deal with the question of drainage (Keay 1942). Across the North Sea,
the Friesland area of the Netherlands had a large and wealthy population
in the period 500 - 1000 A. D., and increasing need for agricultural land
led to building of sea dikes to reclaim land that previously was used for
grazing (Bijker 1996). Water boards developed in response to the need
for a mutual means to coordinate and enforce dike maintenance. These
boards represent some of the earliest democratic institutions in the
Netherlands. Engineering and scientific skills remained alive in the east,
in Byzantium, where the Eastern Roman empire survived for six hundred
years while Western Rome decayed. Of necessity, Byzantium had
become a sea power, sending forth fleets of merchant ships and multi-
oared dromonds (swift war vessels) throughout the Black Sea and
Mediterranean. When the weary soldiers of the first crusades reached
Byzantium's capital city, Constantinople, in 1097, they were amazed and
awed by its magnificence, sophistication, and scientific achievements.
صفحه 18:
Constantinople was built on the hills overlooking the Golden Horn, a
natural bay extending
north of the Bosporus. Marble docks lined the waterfront, over which
passed the spices, furs, timber, grain, and the treasures of an empire. A
great chain could be pulled across the mouth of the Golden Horn to
prevent intrusion by enemy fleets. A series of watch towers extended
along the length of the Sea of Marmara, the Bosphoros, and the south
shore of the Black Sea, and the approach of an enemy fleet could be
signaled to the emperor within hours by an ingenious code using mirrors
by day and signal fires by night (Lamb 1930). The Renaissance era
(about XV - XVI centuries) was a period of scientific and technologic
reawakening, including the field of coastal engineering. While the
standards for design and construction remained those
developed primarily by the Romans, a great leap in technology was
achieved through the development of mechanical equipment and the
birth of the hydraulic sciences including maritime hydraulics (Franco
1996). "The Italian School of Hydraulics was the first to be formed and
the only one to exist before the middle of the 17th century" (Rouse and
Ince 1963).
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Leonardo da Vinci (1465-1519), with his well-known experimental
method, based on the systematic observation of natural phenomenon
supported by intellectual reasoning anda creative intuition, could be
considered the precursor of hydrodynamics, offering ideas and solutions
often
more than three centuries ahead of their common acceptance. Some of
his descriptions of water movement are qualitative, but often so correct,
that some of his drawings could be usefully included in a modern coastal
hydrodynamics text. The quantitative definition and mathematical
formulation of the results were far beyond the scientific capabilities of
the era. Even so, da Vinci was probably the first to describe and test
several experimental techniques now employed in most modern
hydraulic laboratories. To visualize the flow field, he used suspended
particles and dyes, glass-walled tanks, and movable bed models, both in
water and in air.
The movement from kinematics to dynamics proved impossible until the
correct theory of gravitation was developed, some two centuries latter
by Sir Issac Newton (Fasso 1987). The variety of hydro kinematics
problems dealt with in da Vinci's notebooks is so vast that it is not
possible to enumerate them all in this brief review. In the 36 folios
(sheets) of the Codex Leicester (1510), he describes most phenomena
related to maritime hydraulics. Richter (1970) provides an English
translation of da Vinci's notebooks (Franco 1996). The scientific ideas of
| the Italian Renaissance soon moved hevond the confines of that countrv._|
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+ عصر مهندسی عمران و فعلیتهای نظامی(ارتش)
After the Renaissance, although great strides were made in the general
scientific arena, little improvement was made beyond the Roman
approach to harbor construction. Ships became more sea-worthy and
global navigation became more common. With global navigation came
the European discovery of the Americas, Australia, New Zealand,
Indonesia, and other areas of the world, soon followed by migration and
colonization. Trade developed with previously unreachable countries and
new colonies. France developed as the leader in scientific knowledge.
The French "G'enie" officers, who, along with their military task, were
also entrusted with civilian public works, are reportedly the direct
ancestors of modern civil engineers. S'ebastien le Prestre de Vauban
(1633-1707) was a builder of numerous fortresses and perfected the
system of polygonal and star shaped fortifications. His most eminent
public works project was the conversion of Dunkirk into an impregnable
coastal fortress. Apart from the construction of several forts, there were
extensive harbor and coastal works, including the excavation of canals
and harbor basins, the construction of two long jetties flanking the
entrance channel, and the erection of storehouses and workshops.
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A great lock, a masterpiece of civil engineering, was built at the entrance
to the Inner Harbor. Vauban himself designed and supervised the lock
construction. Unfortunately, no more than 30 years after its completion,
the fortress was destroyed as a consequence of the Spanish War of
Succession. Vauban's projects provide
a good example of engineering methods and lucidity. They consisted of
an explanatory memorandum, several drawings, and a covering letter.
The memorandum had four sections:
(1) general background of the scheme;
(2) detailed descriptions of the different parts, with references to the
drawings;
(3) cost estimates;
(4) features and advantages of the work. It was during this time that the
term "Ingenieur" was first used in France, as a professional title for a
scientifically-trained technician in public service.
صفحه 22:
While France enjoyed a leading position in Europe with regard to exact
sciences and their applications to technical problems, a social and
economic revolution later known as the “Industrial Revolution" was
taking place in England. The riding-horse and the packhorse gave way to
the coach, the wagon and the barge. Hard roads and canals replaced the
centuries old soft roads and trails, dusty in dry weather and mud-bound
during rains (Straub 1964). Steam power allowed industry to be
concentrated in factories that required continuous supply of raw
materials and export of manufactured goods.
In the 18th and 19th centuries, advances in navigation and mathematics,
the advent of the steam engine, the search for new lands and trade
routes, the expansion of the British Empire through her colonies, and
other influences, all contributed to the revitalization of sea trade and a
renewed interest in port works. As the volume of shipping grew, more
vessels were needed and as the dimensions of the new vessels became
larger, increased port facilities were necessary. Ports of the world
experienced growing pains for the first time since the Roman era, and,
except for the interruption caused by two world wars, port needs
continue to grow (Quinn 1972).
صفحه 23:
سپاه مهندسان ارتش آمریکا:
Since the formation of the United States, Army engineers and the Corps
of Engineers have been responsible for or intimately associated with a
wide variety of civil projects and improvements to waterways, ports, and
navigation systems. The following paragraphs summarize the history of
the U.S. Army Corps of Engineers (USACE) and outline some of the Corps'
early efforts in coastal and navigation improvements. The origins of the
USACE date to June of 1775, at the beginning of the American War of
Independence, when the Second Continental Congress authorized
General Washington to assign a "chief engineer" for the “grand army"
(Parkman 1978). General Washington selected Colonel Richard Gridley, a
seasoned artilleryman, who had been preparing a line of fortifications
around Boston during the early weeks of the war.
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500۷ 01 6۳9۱۴66۲5, ۵۳10 ۱۳ ۳۱۵۲۵ 01 17/7/3, ۲6 Continental Congress finally
commanded by Louis LeBégue Du Portail, an officer recruited by the
American mission in France. The corps was a vital unit of the Continental
Army until disbanded in November 1783 with the arrival of peace. When
war between France and England broke out in the 1790s Congress
authorized President Washington to begin construction of a system of
fortifications along the coast. In 1802, in anticipation of the European
belligerents signing a treaty of peace, Congress cut back and
reorganized the army and created a separate corps of engineers, limited
at that time to sixteen officers (Parkman 1978). The Act of March 16,
1802 had other far-reaching consequences, as it provided further that
the Corps was to constitute the personnel of a military academy at West
Point. Congress had recognized the almost complete absence of trained
military and civil engineers in the United States, and, in effect,
established a national college of engineering. West Point was the only
school in the country to graduate engineers until 1824, when Rensselaer
Polytechnic Institute was formed. Quickly becoming the growing nation's
primary source of engineering expertise, the Corps first concentrated on
constructing and maintaining strategically-placed coastal fortifications to
repel naval attacks. But soon it became concerned with civil functions as
it planned and executed the national
internal improvement program initiated in the 1820s (Maass 1951).
صفحه 25:
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erm. (Dh te hr (Becker cgemrrzit karl ser un correc out by tar Tray Deyareren, hick hed معدو بت تطح ا شإ يمسجو وسار
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Garvey Det, hick Prectket kare Deore std ho bur a prd 1D, 6660: rere be یه الم سا سس ای ماس
mid-1820s Corps of Engineers officers عط لاه عمد اد طم سد م عمسب بوب مان مسقم
were busy surveying the Ohio and lower Mississippi Rivers and the Great
Lakes, identifying navigation impediments, and proposing improvements and
new routes. Only a month later, on May 24, 1824, President Monroe signed
the first Rivers and Harbors Act, which authorized the President to
appropriate Federal monies to improve navigation on the Ohio and
Mississippi Rivers. By 1829, Army engineers were using steam-powered
snagboats to remove snags and floating trees and to dig out sandbars that
impeded river traffic. Subsequent acts authorized a wide variety of internal
improvements and assigned Army engineers to direct and manage these
projects. Work soon began on a number of challenging locations that were
deemed critical for the growth of a growing nation.
صفحه 26:
Hazardous navigation conditions on the Great Lakes also called for the
rapid improvement of harbors. With the passage of the Rivers and Harbors
Act, Congress voted a $20,000 appropriation for deepening the channel at
the harbor of Presque Isle (at Erie, Pennsylvania) on Lake Erie (Drescher
1982). Signaling the beginning of federal involvement in the development
of harbors on the Great Lakes, the USACE now maintains over 600
navigation projects throughout these waterways. One of the USACE's first
civil projects on an ocean coast was repairing Long Beach at Plymouth,
Massachusetts. The beach was a long, narrow sand spit that formed the
town's harbor. Constantly endangered by waves and wind, it had been a
subject of concern to the citizens of the town as early as 1702, when they
made it a crime to fell its trees or fire the grass. The congressional
appropriation of $20,000 on May 26, 1824, "to repair Plymouth Beach in the
state of Massachusetts, and thereby prevent the harbour at that place from
being destroyed" initiated the Corps' civil works mission in New England.
Corps officers supervised local agents, who built a cribwork breakwater
along the beach's outer shore and erected brush
fences and planted grass to stabilize the sand. Similar projects were
undertaken at nearby Duxbury and other beaches in New England
(Parkman 1978). The pattern whereby Corps specialists supervise local
contractors has continued to this day for most civil works projects.
Over the succeeding century and a half, the USACE's role in civil works
grew dramatically, in step with the growth of the nation's population and
economy. To adequately cover this interesting story in the CEM would risk
doubling its size, so readers are referred to a series of books that document
صفحه 27:
(Pre ی لسالیی هی ۵00۵( سب راهم لمیر
صفحه 28:
صفحه 29:
The Study of Coast:
Coasts can be studied in several different ways dependent upon their
classification:
*Erosional or depositional
*Sediment type (clastic: shingle and sand; or muddy)
*Submergent or emergent
Tectonic setting
*Process-based: wave dominated, tide dominated and wind
dominated - the agents of erosion
صفحه 30:
Wind Dominated
Dunes
*Questions & Answers
=Cause and Effect
Wave Dominated Tide Dominated
+Knowledge’& Understanding
(French, 1997)
Shore PlatformsMudflats Sand
Cliffs Sandflats
Beaches Salt Marshes
Spits, TombolosMang
5 Delta
Energy
High Low
صفحه 31:
The Coastal System
(Hansom, 1988)
صفحه 32:
صفحه 33:
سیستم ساحلی
Coastal Systems:
“coastal systems vary primarily in response to wave
intensity and tidal currents
“breaking waves (and resultant currents) provide
most of the systemic energy
*several additional factors also influence coastal
processes and landforms
5 original geology of the coastline
*relative ‘erodibility’ of regional bedrock
*sea level variations (global and local tectonic or
_glacio-eustatic changes)
“coastal systems typically characterized as erosional
or depositional _
*erosional or depositional nature of any coastline
varies with the systemic energy
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Beach
Offshore ‘Nearshore- ‘Shore Coast
Backshore
Foreshore
هت
Breakers
Low tide
breaker line Low tide shoreline
Copyright © 2008 Pearson Prentice Hall Inc.
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Cliff
Dacia re سه Nearshore zone ———- Offshore zone
I
با Surf ١ مه
وا ما Zone ۱ zone |
Low tide ١ 1
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قلمرو محدوده های مختلف در ساحل
) اسف کرلنه دور یا پیشکرالنهع200 0۵۴۲5۳0۲6(
-دورترين بخش به خط ساحلى
عمقأبدريا در لينمنطقه غالبا بيشتر از نصفطوللمواج وارده --
لمواج نمىة وانند در لينمحدودم شكستاه شوند و روعیستر تاثیر مورفولوژیکهاشته باشند --
ب - منطقه مجاور ساحلى: (©206 51016 81831 )
دراين محدوده امواج وارده به ساحل متحمل بيشترين تغييرات مى كردند
ایی رسوبات به طور واقعى در همين منطقه صورت مى كيرد.
-اين محدوده در مطالعات زئومورفولوزى ساحلى از اهميت خاصی برخوردار است
- شامل سه محدوده مستقل با مسخصات ويزه ميباشد (منطقه شکست ۰ منطقه خیزاب » منطقه يورش امواج)
ج - منطقه پس کرانه (20۳06 516/0۲6)
این منطقه در سطحی بالاتر از آنچه که برای امواج درا قابل حصول باشد فرار گرفته و تنها در هنگام طوفا
های شدید آنهم اگر با مد یا آب بالای استثنانی ( بالاترین مد ) همراه باشند تحت تاثیر مستقیم امواج قرار می
كيرد
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طبقه بندی سواحل
Coastal Classification
معروف ترین سیستم های طبقه بندی سواحل
**طبقه بندی ژئوتکتونیکی زوس ( (Suess 4998
**طبقه بندی ژنتیکی جانسون ( 4969 )4
> طبقه بندی تکتونیکی کوتون ( 1952 - 0100 )
* طبقه بندی شپارد ) 1963 ( Shepard
*** طبقه بندی والنتین ( 0868 )
۶ طبقه بندی ژئومورفولوژیکی اینمن و نورستورم (19720)
صفحه 39:
انواع سیستمهای طبقه بندی بر اساس دو عامل شکل و فرایند
ساحلی ( فرم و پروسه )
الف - طبقه بندی سواحل بر اساس تغییرات سطح آب دریا .( جنسرن - 0600 و والتین
«eso
سواحل از آب خارج شدهع2۳6۲96۳) )
سولحلغوطه ور 581/۶8616۶
ب - طبقه بندی بر اساس تغیبرات ساختار (تکتونیکی) زمین شناسی نوردستروم( (GPO
0)- سواحل تصادمی که در مناطق همگرایی صفحه های تکتونیکی شکل می گيرند. کوه های ساحلی آند در
آمریکای جنوبی
©)سواحل با لبهدتباله دار در مناطقی که دو صفحه تکتونیکی از هم فاصله می گیرند سواحل کارولیتا در آمریکای
شمالی و سواحل دریای سرخ
0)سواحل حاشیه ای دریاء شامل اغلب مناطق دلتاهای آبرفتی یا رودخانه ای
) سواحلی که در مناطق استقرار صفحات تکتونیکی پایدار واقعند( مانند سواحل هند و استرالیا)
ج - طبقه بندی سواحل بر اساس نوع فرایند های ساحلی (دیریس 900 و 4 (OO
0)محیط هایی با امواج طوفانی کوچک و بزرگ از همه جهات؛ سواحل صخره ای و سکو های ساحلی
6) محیط های ساحلی با امواج آرام. لند فرم های ماسه ای نهشته گذاری شده
©)محيط هاى ساحلى نسبتا محصور و حفاظت شده که فعالیت امواج توسط پوشش یخ در عرض های جغرافیایی
بالا به شدت محدود شده
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فرایندهای ساحلی
Coastal Processes
Coastal Form [Dynamic over Space
Si ۴ & Time
Equilibrium
Wind, Waves,
‘Currents
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۱۷۷۵۵۲۳۱۵۲۱۸9 6 ۲۵0۱
What is?
Weathering: Breakdown of rock (Geology) to form sediment in situ
Weathering is a set of physical, chemical and biological processes that alter the physical and
‘chemical state of rocks and soil at or near the earth's surface. Rock and soil is altered
physically by disintegrating and chemically by decomposing. Nearly all weathering involves
water, mostly directly: frost shattering, wetting and drying, salt weathering, and all chemical
weathering is in solution. That is, weathering is climatically driven and thus the term
weathering. Because weather and climate occur at the earth's surface, the intensity of
weathering decreases with depth and most of it occur within less than a metre of the surface
of Soil and rock.
Erosion:Transport of weathered material from one location to another... The wearing
away of land or the removal of beach and/or dune sediments by wave action, tidal currents,
wave currents, drainage, or wind. Erosion includes, but is not limited to, horizontal recession
and scourand can be induced or aggravated by human activities.
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طبقه بندي سواحل
ChissFivaioa ورن
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معروف ترین سیستم هاي طبقه بندي سواحل عبارتند:
))طبقه بندی زوس ۰668
)طبقه بندي ژنتیکی جانسون ( 909 )۰
0) طبقه بندي تکتونیکی کوتون 0
<)طبقه بندي شپارد 465
)طبقه بندي ولنتین ( 4965 )
)طبقه بندي ژئومورفولوژیکی اینمن و نورستورم (49720)
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الف - طبقه بندي سواحل بر اساس تغیبرات سطح آب دریا :
جانسون - 909 و والنتين 496
سواحل از آب خارج شده: Cwerewe
سواحل غوطه ور : GOCOERGEODCE
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ب - طبقه بندي بر اساس تغییرات ساختار- (تکتونیکی)
زمین شناسی:
نوردستروم 619780
- سواحل تصادمی که در مناطق همگرایی صفحه هاي تکتونیکی شکل می گیرند
0- سواحل با لبه دنباله دار در مناطقی که دو صفحه تکتونیکی از هم فاصله می گیرند تشکیل می شوند
ale حاشیه اي دریا که گروه بسیار متنوعی از اشکال ساحلی همراه با بسياري از ویژه گيهاي سواحل
داراي لبه دنباله دار را شامل می شوند و اغلب مناطق دلتاهاي آبرفتی یا رودخانه اي را در بر می گیرند.
) سولحلی که در مناطق استقرار صفحات تکتونیکی پایدار واقعند ( مانند سواحل هند و استرالیا P
صفحه 46:
ج - طبقه بندي سواحل بر اساس نوع فرايند هاي ساحلى
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