Breakwaters are structures that protect coastal areas from wave attack. They provide shelter for ports and harbors by manipulating sand transport and trapping sand. There are various types of breakwaters such as rubble mound, vertical wall, reef, piled, and combinations. The appropriate type depends on factors like materials availability, water depth, foundations, and costs. Vertical wall breakwaters resist loads through friction and soil bearing capacity and can fail through sliding, overturning, or local scour/erosion. Breakwaters are important for protecting coastal infrastructure from hazards while considering economics and suitable design.
The document discusses different types of breakwaters used to protect coastal areas from wave attack. It describes rubble mound breakwaters, vertical-wall breakwaters, and floating breakwaters. Rubble mound breakwaters are constructed from natural rubble or stone and dissipate wave energy through breaking. Vertical-wall breakwaters use a vertical wall structure and reflect wave energy. Floating breakwaters are removable structures constructed from caissons or pontoons that are anchored but less effective against long waves. The document provides details on the characteristics, uses, advantages, and disadvantages of each type of breakwater.
- Jetties are structures built into the sea to protect harbors and influence water currents. They divert river currents away from banks and control navigation. In seas, jetties extend from shore to deep water to shelter ships.
- Common types of jetties include random stone, stone and concrete, caisson, crib, and asphalt. Caisson and crib jetties are built off-site and floated into position. Stone and concrete jetties combine rubble and concrete materials.
- Breakwaters are coastal structures that protect harbors from waves and drift. Common types include detached, headland, nearshore, attached, emerged, submerged, and floating breakwaters built of rubble mound, vertical
This document discusses different types of breakwaters. Breakwaters are structures built along coasts to protect areas from wave disturbance. There are three main categories: rubble mound breakwaters, vertical-wall breakwaters, and floating breakwaters. Rubble mound breakwaters are constructed from natural rubble or stone and are the most widely used in Indian ports due to their cost-effectiveness. Vertical-wall breakwaters use concrete blocks or mass concrete and reflect waves without dissipating much energy. Floating breakwaters are removable structures constructed from caissons or pontoons that can be sunk or floated as needed.
A wall or upright or vertical faced breakwater is defined as a big regular wall raised to construct a harbor basin on solid natural or/and artificial foundation to resist the forces and their components generated by incoming water and waves.
Breakwaters, jetties, and groins are coastal structures used to protect harbors and shorelines from wave energy. Breakwaters are structures that reflect and dissipate wave energy to shelter harbors. Jetties are narrow structures that project from the shore into water and provide berths for ships. Groins are structures built perpendicular to the shore to trap littoral drift and protect or build beaches. There are different types of each structure based on materials, permeability, and orientation relative to shorelines and water flow.
Marine coastal structures are human-made structures constructed along coastlines to protect the shore from erosion, flooding, and damage from waves and currents. The document discusses different types of coastal structures such as revetments, bulkheads, seawalls, breakwaters, groins, jetties, coastal bridges, dikes, and levees. Each structure type serves a different purpose, such as stopping water, holding soil, protecting infrastructure and navigation channels, and reducing erosion. The document provides details on the purpose, construction, and characteristics of each structure type.
Breakwaters are structures that protect coastal areas from wave attack. They provide shelter for ports and harbors by manipulating sand transport and trapping sand. There are various types of breakwaters such as rubble mound, vertical wall, reef, piled, and combinations. The appropriate type depends on factors like materials availability, water depth, foundations, and costs. Vertical wall breakwaters resist loads through friction and soil bearing capacity and can fail through sliding, overturning, or local scour/erosion. Breakwaters are important for protecting coastal infrastructure from hazards while considering economics and suitable design.
The document discusses different types of breakwaters used to protect coastal areas from wave attack. It describes rubble mound breakwaters, vertical-wall breakwaters, and floating breakwaters. Rubble mound breakwaters are constructed from natural rubble or stone and dissipate wave energy through breaking. Vertical-wall breakwaters use a vertical wall structure and reflect wave energy. Floating breakwaters are removable structures constructed from caissons or pontoons that are anchored but less effective against long waves. The document provides details on the characteristics, uses, advantages, and disadvantages of each type of breakwater.
- Jetties are structures built into the sea to protect harbors and influence water currents. They divert river currents away from banks and control navigation. In seas, jetties extend from shore to deep water to shelter ships.
- Common types of jetties include random stone, stone and concrete, caisson, crib, and asphalt. Caisson and crib jetties are built off-site and floated into position. Stone and concrete jetties combine rubble and concrete materials.
- Breakwaters are coastal structures that protect harbors from waves and drift. Common types include detached, headland, nearshore, attached, emerged, submerged, and floating breakwaters built of rubble mound, vertical
This document discusses different types of breakwaters. Breakwaters are structures built along coasts to protect areas from wave disturbance. There are three main categories: rubble mound breakwaters, vertical-wall breakwaters, and floating breakwaters. Rubble mound breakwaters are constructed from natural rubble or stone and are the most widely used in Indian ports due to their cost-effectiveness. Vertical-wall breakwaters use concrete blocks or mass concrete and reflect waves without dissipating much energy. Floating breakwaters are removable structures constructed from caissons or pontoons that can be sunk or floated as needed.
A wall or upright or vertical faced breakwater is defined as a big regular wall raised to construct a harbor basin on solid natural or/and artificial foundation to resist the forces and their components generated by incoming water and waves.
Breakwaters, jetties, and groins are coastal structures used to protect harbors and shorelines from wave energy. Breakwaters are structures that reflect and dissipate wave energy to shelter harbors. Jetties are narrow structures that project from the shore into water and provide berths for ships. Groins are structures built perpendicular to the shore to trap littoral drift and protect or build beaches. There are different types of each structure based on materials, permeability, and orientation relative to shorelines and water flow.
Marine coastal structures are human-made structures constructed along coastlines to protect the shore from erosion, flooding, and damage from waves and currents. The document discusses different types of coastal structures such as revetments, bulkheads, seawalls, breakwaters, groins, jetties, coastal bridges, dikes, and levees. Each structure type serves a different purpose, such as stopping water, holding soil, protecting infrastructure and navigation channels, and reducing erosion. The document provides details on the purpose, construction, and characteristics of each structure type.
This document discusses parameters for constructing breakwaters, including conducting hydrographic surveys, geotechnical investigations of the seabed, wave hindcasting to determine wave heights, assessing material needs, and designing the cross-section. It describes basic and advanced methods for geotechnical investigations and outlines three methods for wave hindcasting - using wave rider buoys, statistical computer models, or manual observation with a theodolite. The key parameters that must be determined before breakwater construction can begin are also listed.
This document summarizes techniques for seismic retrofitting of existing structures. It defines seismic retrofitting as modifying structures to make them more resistant to earthquakes. Common retrofitting techniques discussed include adding new shear walls, steel bracing, jacketing columns and beams, using innovative materials like fiber reinforced polymers, base isolation using elastomeric bearings or sliding systems, and installing seismic dampers. The document also discusses retrofitting performance objectives, codes and guidelines, and provides examples of retrofitted structures.
Gravity dams are rigid concrete dams that rely entirely on their weight to maintain stability. They are built with a triangular cross-section to transfer loads directly to strong rock foundations. Famous gravity dams discussed include the Bhakra Dam in India and Fontana Dam in the US. Advantages are that they are durable, allow heights over 700 feet, and have low maintenance costs. However, they require competent foundations and construction is complex. Forces like water pressure, uplift, and earthquakes must be addressed through design to prevent failures by overturning, sliding, tension, or crushing.
6. NAVIGATIONAL AIDS (PHE) GTU 3170623VATSAL PATEL
This document discusses various types of navigational aids that help vessels travel safely through waterways. It describes fixed aids like lighthouses, beacon lights, and lightships as well as floating aids like buoys. Lighthouses are tall towers that emit powerful lights to guide ships, while beacon lights use prominent natural or man-made structures. Buoys are floating markers that delineate channels and hazards. Lightships are small ships equipped with revolving lights that act as lighthouses. Electronic devices like LORAN and radar also help with navigation by determining a ship's position or detecting nearby objects. These various aids are crucial for safe, efficient maritime travel.
The document discusses coastal protection techniques. It begins by explaining the importance of coasts and the need for coastal protection due to erosion from storms and rising sea levels. It then describes hard and soft engineering techniques for coastal protection. Hard techniques include breakwaters, gabions, groynes, revetments, sea walls, and use rigid structures to defend coastlines. Soft techniques like beach nourishment, dune stabilization, and mangroves are more natural and sustainable approaches. The document provides details on various hard and soft techniques, their advantages and disadvantages. It concludes by discussing physical aspects of coastal protection like wave types, wave control through reflection, refraction, and breaking.
Breakwaters are structures built along coastlines to protect harbors, anchorages, and shore areas from wave damage. They work by reflecting and dissipating wave energy. There are several types of breakwaters including detached, headland, nearshore, attached, rubble mound, vertical, and submerged. Planning a breakwater requires detailed surveys of the site hydrography, sea bed geology, wave climate, material needs assessment, and cross-sectional design. Proper planning ensures breakwaters are engineered to withstand local conditions and provide effective coastal protection.
Retaining walls are used to retain earth in a vertical position where there is an abrupt change in ground level. There are several types of retaining walls including gravity, cantilever, counterfort, and buttress walls. Cantilever walls are the most common type for heights up to 8 meters. They consist of a vertical stem and base slab that behave like one-way cantilevers. Counterfort walls include transverse supports called counterforts to reduce bending moments in the stem and slabs. Proper design of the stem, heel slab, toe slab, and foundation depth is required to resist overturning, sliding, soil pressure, and bending failure.
There are several types of coastal protection measures that can be used to reduce erosion. Hard engineering options like groynes, gabion cages, revetments, seawalls, and rip rap absorb wave energy through rigid structures. Groynes interrupt water flow perpendicular to the coast to limit sediment loss. Gabion cages are stacked rock-filled wire cages that act as temporary barriers. Revetments are sloped stone or wood structures that absorb wave energy. Seawalls are massive vertical walls that deflect waves. Rip rap is rock or concrete rubble that minimizes erosion. Beach replenishment involves adding new sediment and is considered soft engineering since it has a more natural appearance and fits better within the environment.
Coastal Protection Measures Hard Engineeringchua.geog
Hard coastal protection measures like seawalls, breakwaters, groynes, and gabions can help defend against wave erosion. Seawalls made of concrete absorb wave energy during storms. Breakwaters are often granite and create shallow water to reduce wave impact on coasts. Groynes prevent longshore drift from transporting materials away from the coast. Gabions are wire cages filled with rocks that reinforce other structures and river banks against erosion.
Coastal structures are constructed along coastlines to protect the shoreline from erosion and flooding, and to support activities like navigation and recreation. Engineers build different types of coastal structures such as seawalls, revetments, breakwaters, and groins to slow erosion, increase access, and support development. Maintaining coastal structures is important for protecting infrastructure, harbors, and coastal communities.
Concrete Armours are also known as Rubble mound breakwaters are mostly built of quarried rock. Larger armour stones are generally used for the outer layer to protect the structure against wave attack. The wave loads during a design storm may show the need for an armour rock size, which cannot be economically produced and transported to the site. Concrete armour units then become a competitive alternative.
This document discusses various techniques for retrofitting concrete structures to make them more resistant to seismic activity and other natural hazards. It defines retrofitting as modifying existing structures to increase resistance. Key techniques mentioned include adding new shear walls, steel bracing, column and beam jacketing with steel or concrete, base isolation using seismic isolators, mass reduction by removing floors, and wall thickening. The document also discusses challenges in retrofitting and standards from Indian codes for earthquake-resistant design. The conclusion emphasizes that retrofitting has matured but expertise is still lacking, and optimization is needed to determine the most cost-effective technique for a given structure.
This document defines harbors and docks and classifies them. It states that a harbor is a sheltered area of sea that provides protection from storms and allows for loading/unloading of vessels. Docks are enclosed areas that keep ships at a uniform level for cargo handling. Harbors are classified as natural, artificial, or semi-natural based on physical protections. They can also be refuge, commercial, fishery, or military harbors based on their functions. Docks include wet docks for berthing ships and dry docks for ship repairs.
This document provides information on the design of vertical wall breakwaters. It discusses different types of vertical wall breakwaters including conventional, vertical composite, horizontal composite, block type, and piled breakwaters. The document outlines the objectives of understanding hydraulic loads, preliminary breakwater design, and comparing vertical wall and rubble mound breakwaters. It also covers functional requirements, loads and resistance considerations, failure modes, and introductory design methods including the use of the PROVERBS parameter map to identify breaking wave conditions. Worked examples of breakwater types and failures are presented.
It contains details of retrofitting techniques and their application in various aspects in historical monuments. It would help to protect several heritage structures from the devastating effect of the earthquake. Some applications are also helpful too counter act the severe effect of the wind load. There are many historical heritages especially in India, are reopened to the public after being retrofitted and renovated.
This document outlines the planning requirements and considerations for developing different types of harbors. Key factors that must be studied in harbor planning include surveys of the site terrain, tides, weather patterns, and depth of waters. The size and features of the harbor must accommodate the intended ships while providing safe anchorage. Requirements vary depending on the harbor type, such as sufficient depth and shelter for commercial harbors, repair facilities for harbors of refuge, and accommodation for naval vessels in military harbors. Proper positioning of harbor elements is important for safe navigation.
This document discusses port planning and characteristics of good seaports. It outlines factors to consider like connectivity, depth, protection from waves, storage, and facilities. It also discusses dry ports, bulk cargo, transshipment ports, ports of call, necessary surveys, regional transportation development, forecasting cargo and passenger demand, and calculating a port's cargo handling capacity. Key aspects include considering infrastructure, operations, traffic potential, natural conditions, and matching supply and demand to utilize port resources effectively.
Navigation aids such as lighthouses, beacon lights, buoys, and lightships are necessary to safely guide vessels through rivers, channels, harbors, and coastal waters. These aids help vessels avoid dangerous zones, follow proper harbor approaches, and locate ports during nighttime and bad weather. There are two main types of navigation aids: fixed aids like lighthouses and beacon lights, and floating aids such as buoys and lightships. Lighthouses are tall tower structures that can be seen from long distances, while beacon lights help identify directions and alignments. Buoys come in different shapes and types to demarcate channels and entrances. Lightships are small ships that act as lighthouses
1. There are three main types of seawalls: vertical, curved, and mound. Vertical seawalls are the easiest to design and construct but can become undermined. Curved seawalls reduce wave reflection and turbulence but are more complex to design. Mound seawalls provide maximum wave energy dissipation but are less durable and have a shorter lifespan.
2. Several seawall systems are described: gravity walls, L-shaped walls with buttresses, and systems that use piles or diaphragm walls to provide support independently of soil weight. Pile-supported systems are less vulnerable to scour but more expensive. Diaphragm systems are flexible and independent of soil surcharge weight.
This document discusses bridge scour, which is the removal of sediment around bridge piers and abutments due to moving water. Scour can undermine bridge foundations and has caused 46 major bridge failures in the US from 1961-1976. The basic components of a bridge are the substructure, which includes piers, abutments and foundations, and the superstructure, which is the deck. Piers can be column or wall types and are vulnerable to scour, which forms scour holes through vortex formation and increased shear stress on sediments. The document presents photos of bridge failures from scour and methods to monitor and protect against scour using gravel bags, rock armor, and sonar scour monitors.
DLW is an integrated plant and its manufacturing facilities are flexible in nature. These can be utilized for manufacture of different design of locomotives of various gauges suiting customer requirements and other products.
Retaining walls are an integral part of any sea facing structure or structures which contain single or multiple basements. The PPT gives a general idea about retaining walls and also focuses on a case study of the retaining wall along the Worli Seaface in Mumbai, India.
This document discusses parameters for constructing breakwaters, including conducting hydrographic surveys, geotechnical investigations of the seabed, wave hindcasting to determine wave heights, assessing material needs, and designing the cross-section. It describes basic and advanced methods for geotechnical investigations and outlines three methods for wave hindcasting - using wave rider buoys, statistical computer models, or manual observation with a theodolite. The key parameters that must be determined before breakwater construction can begin are also listed.
This document summarizes techniques for seismic retrofitting of existing structures. It defines seismic retrofitting as modifying structures to make them more resistant to earthquakes. Common retrofitting techniques discussed include adding new shear walls, steel bracing, jacketing columns and beams, using innovative materials like fiber reinforced polymers, base isolation using elastomeric bearings or sliding systems, and installing seismic dampers. The document also discusses retrofitting performance objectives, codes and guidelines, and provides examples of retrofitted structures.
Gravity dams are rigid concrete dams that rely entirely on their weight to maintain stability. They are built with a triangular cross-section to transfer loads directly to strong rock foundations. Famous gravity dams discussed include the Bhakra Dam in India and Fontana Dam in the US. Advantages are that they are durable, allow heights over 700 feet, and have low maintenance costs. However, they require competent foundations and construction is complex. Forces like water pressure, uplift, and earthquakes must be addressed through design to prevent failures by overturning, sliding, tension, or crushing.
6. NAVIGATIONAL AIDS (PHE) GTU 3170623VATSAL PATEL
This document discusses various types of navigational aids that help vessels travel safely through waterways. It describes fixed aids like lighthouses, beacon lights, and lightships as well as floating aids like buoys. Lighthouses are tall towers that emit powerful lights to guide ships, while beacon lights use prominent natural or man-made structures. Buoys are floating markers that delineate channels and hazards. Lightships are small ships equipped with revolving lights that act as lighthouses. Electronic devices like LORAN and radar also help with navigation by determining a ship's position or detecting nearby objects. These various aids are crucial for safe, efficient maritime travel.
The document discusses coastal protection techniques. It begins by explaining the importance of coasts and the need for coastal protection due to erosion from storms and rising sea levels. It then describes hard and soft engineering techniques for coastal protection. Hard techniques include breakwaters, gabions, groynes, revetments, sea walls, and use rigid structures to defend coastlines. Soft techniques like beach nourishment, dune stabilization, and mangroves are more natural and sustainable approaches. The document provides details on various hard and soft techniques, their advantages and disadvantages. It concludes by discussing physical aspects of coastal protection like wave types, wave control through reflection, refraction, and breaking.
Breakwaters are structures built along coastlines to protect harbors, anchorages, and shore areas from wave damage. They work by reflecting and dissipating wave energy. There are several types of breakwaters including detached, headland, nearshore, attached, rubble mound, vertical, and submerged. Planning a breakwater requires detailed surveys of the site hydrography, sea bed geology, wave climate, material needs assessment, and cross-sectional design. Proper planning ensures breakwaters are engineered to withstand local conditions and provide effective coastal protection.
Retaining walls are used to retain earth in a vertical position where there is an abrupt change in ground level. There are several types of retaining walls including gravity, cantilever, counterfort, and buttress walls. Cantilever walls are the most common type for heights up to 8 meters. They consist of a vertical stem and base slab that behave like one-way cantilevers. Counterfort walls include transverse supports called counterforts to reduce bending moments in the stem and slabs. Proper design of the stem, heel slab, toe slab, and foundation depth is required to resist overturning, sliding, soil pressure, and bending failure.
There are several types of coastal protection measures that can be used to reduce erosion. Hard engineering options like groynes, gabion cages, revetments, seawalls, and rip rap absorb wave energy through rigid structures. Groynes interrupt water flow perpendicular to the coast to limit sediment loss. Gabion cages are stacked rock-filled wire cages that act as temporary barriers. Revetments are sloped stone or wood structures that absorb wave energy. Seawalls are massive vertical walls that deflect waves. Rip rap is rock or concrete rubble that minimizes erosion. Beach replenishment involves adding new sediment and is considered soft engineering since it has a more natural appearance and fits better within the environment.
Coastal Protection Measures Hard Engineeringchua.geog
Hard coastal protection measures like seawalls, breakwaters, groynes, and gabions can help defend against wave erosion. Seawalls made of concrete absorb wave energy during storms. Breakwaters are often granite and create shallow water to reduce wave impact on coasts. Groynes prevent longshore drift from transporting materials away from the coast. Gabions are wire cages filled with rocks that reinforce other structures and river banks against erosion.
Coastal structures are constructed along coastlines to protect the shoreline from erosion and flooding, and to support activities like navigation and recreation. Engineers build different types of coastal structures such as seawalls, revetments, breakwaters, and groins to slow erosion, increase access, and support development. Maintaining coastal structures is important for protecting infrastructure, harbors, and coastal communities.
Concrete Armours are also known as Rubble mound breakwaters are mostly built of quarried rock. Larger armour stones are generally used for the outer layer to protect the structure against wave attack. The wave loads during a design storm may show the need for an armour rock size, which cannot be economically produced and transported to the site. Concrete armour units then become a competitive alternative.
This document discusses various techniques for retrofitting concrete structures to make them more resistant to seismic activity and other natural hazards. It defines retrofitting as modifying existing structures to increase resistance. Key techniques mentioned include adding new shear walls, steel bracing, column and beam jacketing with steel or concrete, base isolation using seismic isolators, mass reduction by removing floors, and wall thickening. The document also discusses challenges in retrofitting and standards from Indian codes for earthquake-resistant design. The conclusion emphasizes that retrofitting has matured but expertise is still lacking, and optimization is needed to determine the most cost-effective technique for a given structure.
This document defines harbors and docks and classifies them. It states that a harbor is a sheltered area of sea that provides protection from storms and allows for loading/unloading of vessels. Docks are enclosed areas that keep ships at a uniform level for cargo handling. Harbors are classified as natural, artificial, or semi-natural based on physical protections. They can also be refuge, commercial, fishery, or military harbors based on their functions. Docks include wet docks for berthing ships and dry docks for ship repairs.
This document provides information on the design of vertical wall breakwaters. It discusses different types of vertical wall breakwaters including conventional, vertical composite, horizontal composite, block type, and piled breakwaters. The document outlines the objectives of understanding hydraulic loads, preliminary breakwater design, and comparing vertical wall and rubble mound breakwaters. It also covers functional requirements, loads and resistance considerations, failure modes, and introductory design methods including the use of the PROVERBS parameter map to identify breaking wave conditions. Worked examples of breakwater types and failures are presented.
It contains details of retrofitting techniques and their application in various aspects in historical monuments. It would help to protect several heritage structures from the devastating effect of the earthquake. Some applications are also helpful too counter act the severe effect of the wind load. There are many historical heritages especially in India, are reopened to the public after being retrofitted and renovated.
This document outlines the planning requirements and considerations for developing different types of harbors. Key factors that must be studied in harbor planning include surveys of the site terrain, tides, weather patterns, and depth of waters. The size and features of the harbor must accommodate the intended ships while providing safe anchorage. Requirements vary depending on the harbor type, such as sufficient depth and shelter for commercial harbors, repair facilities for harbors of refuge, and accommodation for naval vessels in military harbors. Proper positioning of harbor elements is important for safe navigation.
This document discusses port planning and characteristics of good seaports. It outlines factors to consider like connectivity, depth, protection from waves, storage, and facilities. It also discusses dry ports, bulk cargo, transshipment ports, ports of call, necessary surveys, regional transportation development, forecasting cargo and passenger demand, and calculating a port's cargo handling capacity. Key aspects include considering infrastructure, operations, traffic potential, natural conditions, and matching supply and demand to utilize port resources effectively.
Navigation aids such as lighthouses, beacon lights, buoys, and lightships are necessary to safely guide vessels through rivers, channels, harbors, and coastal waters. These aids help vessels avoid dangerous zones, follow proper harbor approaches, and locate ports during nighttime and bad weather. There are two main types of navigation aids: fixed aids like lighthouses and beacon lights, and floating aids such as buoys and lightships. Lighthouses are tall tower structures that can be seen from long distances, while beacon lights help identify directions and alignments. Buoys come in different shapes and types to demarcate channels and entrances. Lightships are small ships that act as lighthouses
1. There are three main types of seawalls: vertical, curved, and mound. Vertical seawalls are the easiest to design and construct but can become undermined. Curved seawalls reduce wave reflection and turbulence but are more complex to design. Mound seawalls provide maximum wave energy dissipation but are less durable and have a shorter lifespan.
2. Several seawall systems are described: gravity walls, L-shaped walls with buttresses, and systems that use piles or diaphragm walls to provide support independently of soil weight. Pile-supported systems are less vulnerable to scour but more expensive. Diaphragm systems are flexible and independent of soil surcharge weight.
This document discusses bridge scour, which is the removal of sediment around bridge piers and abutments due to moving water. Scour can undermine bridge foundations and has caused 46 major bridge failures in the US from 1961-1976. The basic components of a bridge are the substructure, which includes piers, abutments and foundations, and the superstructure, which is the deck. Piers can be column or wall types and are vulnerable to scour, which forms scour holes through vortex formation and increased shear stress on sediments. The document presents photos of bridge failures from scour and methods to monitor and protect against scour using gravel bags, rock armor, and sonar scour monitors.
DLW is an integrated plant and its manufacturing facilities are flexible in nature. These can be utilized for manufacture of different design of locomotives of various gauges suiting customer requirements and other products.
Retaining walls are an integral part of any sea facing structure or structures which contain single or multiple basements. The PPT gives a general idea about retaining walls and also focuses on a case study of the retaining wall along the Worli Seaface in Mumbai, India.
DLW is an integrated plant and its manufacturing facilities are flexible in nature. These can be utilized for manufacture of different design of locomotives of various gauges suiting customer requirements and other products.
CETPA Infotech Pvt. Ltd is an ISO certified training company that offers summer vocational training programs in software, embedded systems, and other technologies. The training is designed to prepare students for placements by teaching industry-relevant skills. CETPA has trained over 45,000 students over 9 years across multiple locations in India and abroad. The document provides details on CETPA's training programs, schedules, fees, and registration process.
diesel locomotive works training report by somesh dwivedisomesh dwivedi
4week summer training report on D.L.W. Varanasi by Somesh Dwivedi.
on the topics 1.-Heavy Weld Shop(HWS)
2.- Heavy Machine Shop(HMS)
3. Light Machine Shop(LMS)
4. Truck Machine Shop(TMS)
The document lists various cities and locations around the Black Sea, including Russian cities like Adler, Gelendjik, and Tuapse as well as Ukrainian cities like Feodosiya, Sudak, Alushta, Yalta, and Sevastopol. It also mentions the Kerch Strait and Russian and Ukrainian coastal locations like Kinburn and Odessa. The document ends with a reference to a Mozart symphony.
- Climate change is increasing the frequency and severity of disasters like floods, droughts, storms and hurricanes. This is negatively impacting food security, health, and livelihoods in many parts of the world.
- Data shows that the number of weather-related disasters has increased six-fold since the 1980s, with 95% of people affected by natural hazards in 2009 impacted by extreme weather events. Crop yields are projected to fall substantially in many regions.
- Adaptation is necessary to address the impacts of climate change and promote sustainable development, especially for vulnerable communities. Integration of climate change adaptation and disaster risk reduction is important at community, policy, and program levels.
Coastal areas face problems of erosion and flooding due to rising sea levels and increased storm activity. This threatens homes, businesses and tourism. Coastal defenses use hard engineering like seawalls and groynes, or soft engineering like beach nourishment and managed retreat, to protect coastlines. However, all methods have disadvantages such as visual impacts or increasing erosion elsewhere. Coastal resorts also struggle with declining visitor numbers from overseas competition and require solutions like improving attractions to revitalize their economies.
Dokumen ini merupakan laporan perencanaan pelabuhan di Pulau Belitung yang mencakup perencanaan letak pelabuhan, fasilitas, layout, dan alur pelayaran. Perencanaan pelabuhan mempertimbangkan kapasitas kapal, kedalaman air yang dibutuhkan, dan fasilitas pendukung seperti dermaga, gudang, dan pemecah gelombang.
This document discusses different types of dams including rock fill dams, gravity dams, buttress dams, arch dams, and beaver dams. It provides details on the construction and design of rock fill dams, including that they are built of large rock fragments and boulders with an impervious core or zone. The document also compares the key differences between rock fill dams and earth fill dams. Finally, it discusses the classification of earth fill dams based on construction method and soil characteristics.
The document provides a report on vocational training received by four students at various Indian Railway locations. It summarizes their visits to Sealdah station power house and substation where they observed feeders, transformers, and the 25kV autotransformer system. It also describes visits to Barasat car shed where they learned about overhead electrification systems, pantographs, and traction motors. Their final visit was to Narkeldanga car shed where they examined equipment like pantographs, transformers, rectifiers, and protection circuits used in electric multiple unit trains.
Retaining walls are structures used to retain soil or rock in a vertical position. Common materials used include wood, steel, concrete, and gabions. Retaining walls are classified as externally or internally stabilized. Externally stabilized include in-situ and gravity walls. Internally stabilized include reinforced soils and in-site reinforcement. Design considerations include ensuring stability against overturning, sliding, and overloading soils. Design also accounts for active and passive earth pressures. Common gravity wall types are massive gravity, crib, and cantilever walls. In-situ walls include sheet pile, soldier pile, and slurry walls. Reinforced and geosynthetic retaining walls are advanced wall types.
The Diesel Locomotive Works (DLW) in Varanasi, India, is a production unit owned by Indian Railways, that manufactures diesel-electric locomotives and its spare parts. It is the largest diesel-electric locomotive manufacturer in India.
Locally it is called as D L W.
This technical report summarizes a visit to an electric locomotive workshop. It describes the key internal parts of an electric locomotive such as the transformer, rectifier, armature converter and traction motors. It provides photos and explanations of the control desk, instrumentation, electrical equipment and auxiliary systems used for cooling. Advantages of electric locomotives are highlighted like reduced emissions, maintenance and noise compared to diesel. The report concludes the workshop helped learn about electric locomotives used extensively in Indian railways.
This document discusses different types of retaining walls, including gravity, cantilevered, counter fort, precast concrete, and sheet pile walls. It describes factors that influence retaining wall design such as soil type, water table height, and subsurface water movement. The key forces that act on retaining walls are also examined: pressure at rest, active earth pressure, and passive earth pressure. Finally, five common modes of retaining wall failure are identified: sliding, overturning, bearing capacity, shallow shear, and deep shear failures.
Cruise missile technology By shailesh shukla pptSHAILESH SHUKLA
Cruise missiles are small, pilotless airplanes powered by turbofan engines that can precisely deliver bombs up to 1,000 miles away. They use various guidance systems like inertial navigation, terrain contour matching, and digital scene mapping to navigate to their targets. Inertial navigation uses accelerometers and gyroscopes to measure movement, while terrain contour matching compares onboard radar measurements to pre-recorded terrain maps to determine location. Cruise missiles offer advantages like low cost and small size, but also have disadvantages like lack of reusability and vulnerability to defenses. Their guidance systems require careful design for accurate target interception.
Cruise Missile Technology By Takalikar Mayur pptmayur takalikar
This document summarizes information about cruise missile technology. It describes cruise missiles as small, self-navigating unmanned aerial vehicles that can deliver warheads over long distances with precision. Key aspects discussed include guidance systems like inertial navigation and terrain contour matching; categories based on size, speed, range and launch platform; and historical examples like the Tomahawk and BrahMos missiles. Advantages are their small size and accuracy, while limitations are lack of reusability and vulnerability to interception. Recent uses demonstrate over 90% success rates in American strikes on Afghanistan and Iraq.
This document defines and categorizes different types of powered guided munitions. It outlines their key parts like guidance and propulsion systems. It then describes different modes like air-to-air and surface-to-surface. Finally, it details various guidance systems for powered munitions including line-of-sight homing, inertial navigation, and satellite guidance as well as ballistic and cruise missiles.
The document discusses standards and guidelines for architectural design of shopping malls. It provides details on column spacing, store depths, clear heights, parking requirements, shop sizes and layouts, circulation areas, exits and staircases. Standards for showcases, shelving, aisle widths, and mechanical systems are also outlined. Shopping malls should allow 5-6 parking spaces per 1000 square feet and exits should be within a travel distance of 30 meters. Staircases and corridors require minimum widths and heights to facilitate safe evacuation.
Coastal protection structures are constructed to protect harbors and infrastructure from ocean waves and erosion. The document discusses five common types of coastal protection structures: seawalls, bulkheads, groins, jetties, and breakwaters. Seawalls run along shorelines and are designed to withstand wave action through curved or stepped faces. Bulkheads retain earth and come in gravity or anchored sheet pile designs. Groins reduce erosion by altering currents and waves, while jetties extend into water to block sandbar formation and currents. Breakwaters shelter areas in three forms: offshore, shore-connected, or rubble mound.
Advanced technologies for costal protectionLINGA SAI TEJA
This document discusses various advanced technologies for coastal protection in India. It introduces the importance of protecting India's long coastline from flooding and erosion. It then describes different methods of coastal protection including sea walls, breakwaters, groins, gabions, revetments, bulkheads, and beach nourishment. It provides details on each method and examples of their use. The document emphasizes the importance of coastal protection for safety, economic, and environmental reasons. It notes that development and habitat loss threaten coastlines and that protection methods should consider social, economic and environmental impacts.
This document discusses coastal erosion, its causes, impacts, and various mitigation approaches. It identifies key physical parameters that contribute to coastal erosion like waves, tides, and vegetation. Approaches to mitigate erosion include hard engineering methods like seawalls, breakwaters, and groynes, as well as soft engineering methods like beach nourishment, relocating structures, planting mangroves, and growing coral reefs. Hard structures provide direct protection but can have negative environmental impacts. Soft methods aim to work with natural coastal processes but have challenges with feasibility and cost. Overall management requires consideration of engineering and environmental factors.
Large scale coastal development can cause problems if not properly managed through coastal protection and planning. Coastal management approaches include hard engineering using physical structures to reduce erosion, and soft engineering which focuses on non-structural planning and allowing natural processes. Specific hard engineering measures have benefits but also negative consequences, while soft engineering through beach nourishment, relocating properties, mangrove planting, and stabilizing dunes can help protect coasts but face challenges.
Groynes are barriers built perpendicular to the shore to slow longshore drift and build up beaches. They allow beach build up which protects against erosion and attracts tourism. However, they can be seen as unattractive and costly to build and maintain.
Breakwaters are used to protect harbors and stretches of coastlines, usually made of concrete or stone blocks strong enough to withstand waves. They must be built in deep water, making them expensive.
Gabions are metal cages filled with rocks stacked to form simple walls. They provide short-term erosion protection but are easily damaged and rust quickly. Gabions are relatively inexpensive but have a short lifespan.
Revetments are sloped structures that break up wave energy
1) Breakwaters are artificial protective barriers constructed to enclose harbors and keep harbor waters undisturbed by heavy seas. They enable harbors to be used as safe anchorages and allow cargo loading in calm waters.
2) There are several types of breakwaters, including rubble mound, mound with superstructure, and upright wall breakwaters. Rubble mound breakwaters use layers of stone and core materials. Mound with superstructure breakwaters have a solid structure atop the mound. Upright wall breakwaters function like solid walls.
3) Breakwaters provide shelter from wave action, lowering tidal energy and sediment transport. They allow harbors to be used safely and facilitate marine operations and berthing of small boats
The document discusses different methods of coastal management to reduce erosion and flooding risks along coastlines. It describes hard engineering options like groynes, sea walls, revetments, and rock armour that use rigid structures to reduce wave energy. It also describes soft engineering options like beach nourishment, beach reshaping, and managed retreat that are more sustainable and natural approaches. Managed retreat in particular allows the sea to reclaim formerly flooded land to create salt marshes that can absorb wave energy and flooding impacts.
Breakwaters are structures built along coasts to protect harbors, anchorages, and shorelines from wave damage. They work by reflecting and dissipating wave energy before it reaches the protected area. There are several types of breakwaters including detached, headland, nearshore, attached, rubble mound, vertical, and submerged. The appropriate type depends on factors like water depth, wave climate, and material availability. Successful breakwater design requires detailed surveys of seabed conditions, wave patterns, and material needs to ensure the structure is stable and effective.
Breakwaters are structures built along coastlines to protect harbors, anchorages, and shore areas from wave damage. They work by reflecting and dissipating wave energy. There are several types of breakwaters including detached, headland, nearshore, attached, rubble mound, vertical, and submerged. Planning a breakwater requires detailed surveys of the site hydrography, sea bed geology, wave climate, material needs, and cross-sectional design. Proper planning ensures breakwaters are engineered to withstand local conditions and provide effective coastal protection.
Offshore breakwaters can be either floating or fixed structures designed to absorb wave energy and reduce coastal erosion. They are commonly used in harbors but can also protect beaches. Breakwaters prevent wave force and erosion effectively but may be visually unappealing. Gabions, which are wire cages filled with rocks, can be stacked into various shapes and used as retaining walls or erosion barriers. They are a cheaper alternative to breakwaters but also present visual pollution. Groynes prevent longshore drift by blocking the lateral movement of sand along the coast but require maintenance and are considered an eyesore by some. Revetments are sloped concrete structures that absorb wave energy through their design and prevent erosion of coastal cliffs and hills. While effective, they
Offshore breakwaters can be either floating or fixed structures designed to absorb wave energy and reduce coastal erosion. They are commonly used in harbors but can also protect beaches. Breakwaters prevent wave force and erosion effectively but may be visually unappealing. Gabions, which are wire cages filled with rocks, can be stacked into various shapes and used as retaining walls or erosion barriers. They are a cheaper alternative to breakwaters but also present visual pollution. Groynes prevent longshore drift by blocking the lateral movement of sand along the coast but require maintenance and are considered an eyesore by some. Revetments are sloped concrete structures that absorb wave energy through their design and prevent erosion of coastal cliffs and hills. While effective, they
Offshore breakwaters can be either floating or fixed structures designed to absorb wave energy and reduce coastal erosion. They are commonly used in harbors but can also protect beaches. Breakwaters prevent wave force and erosion effectively but may be visually unappealing. Gabions, which are wire cages filled with rocks, can be stacked into various shapes to control erosion and silt runoff in a flexible and inexpensive way but can also appear unsightly. Groynes prevent longshore drift by blocking the lateral movement of sand along the coast but require maintenance and are sometimes considered an eyesore. Revetments are sloped concrete structures that absorb wave energy through their design and gravity to protect cliffs and hills from erosion in a way that can blend
The document provides an introduction to various coastal structures used for coastal protection. It describes sea dikes, sea walls, revetments, emergency protection, bulkheads, groynes, jetties, breakwaters, and detached breakwaters. Each coastal structure is defined and its applicability is discussed. The document categorizes coastal protection structures as coastal protection, shore protection, beach construction, management solutions, and sea defense. It aims to give an overview of different types of structures used to protect coasts from erosion, flooding, and damage from waves and currents.
This document summarizes guidelines and strategies for designing tsunami-resistant structures. It discusses how typical buildings fail in tsunamis due to high water pressure and flow forces. It then outlines design recommendations like using reinforced concrete, having open first floors, deep foundations, and redundancy. Several case studies of innovative tsunami-resistant structural designs are presented, including elevated towers, pier-shaped structures, and personal survival capsules. Forces on different structure types are analyzed. The document concludes with additional design guidelines like using shear walls and having smaller sea-facing faces.
Sea walls are constructed structures built parallel to coastal shores to protect inland areas from erosion. There are several types of sea walls including curved concrete walls, vertical walls, and revetment walls made of rock and concrete. Examples provided include the Galveston sea wall in Texas and the Saemangeum sea wall in South Korea. Sea walls can control erosion and reduce flooding but also have disadvantages like high costs, ecosystem impacts, and limited lifespans.
Sea walls are hard engineering structures built along coastlines to physically stop waves from hitting the shore. They are expensive to build, costing between £1000-5000 per meter, and require significant material. While protecting property and absorbing wave energy, sea walls can accelerate erosion elsewhere, damage beaches, disrupt sediment flow, and have ongoing maintenance costs with a lifespan of only 30-50 years. Rock armour and gabions are alternatives that use rock blocks and wire cages to dissipate wave energy at a lower initial cost but with disadvantages like appearance and limited scale of protection. Revetments are sloped variations of sea walls that are more effective at dissipating wave energy but are also very expensive to build and maintain while taking up more space and
presentation was provided by Prof W.U Chandrasekara
Department of Zoology and Environmental Management
For Coastal and Marine resource management course
The document discusses various hard engineering methods for coastal management including seawalls, breakwaters, and groynes.
Seawalls are sloping or vertical concrete walls built parallel to the coast to absorb wave energy. However, the reflected waves increase erosion below the wall.
Breakwaters are structures built parallel to the coast some distance away to break wave force before reaching land. They reduce erosion but can cause erosion in unprotected areas.
Groynes are perpendicular structures that trap sediment on the side facing longshore drift, building up beaches but potentially causing erosion on the opposite side if not spaced correctly.
All hard structures have benefits but also problems like erosion in unprotected areas and need for regular maintenance. Soft
The document discusses various methods for mitigating coastal erosion, including both hard and soft structural approaches. Hard structural methods discussed include jetties, seawalls, groins, revetments, and breakwaters. Soft structural approaches include beach nourishment and sand dune stabilization. Each method is described and their advantages and disadvantages are provided. In conclusion, coastal erosion affects the environment and communities require long-term strategies informed by science and engineering to control erosion.
Hard engineering strategies like sea walls, rock armor, groynes, and gabions are used to protect coastal areas from storm waves and erosion. These structures work by blocking and reflecting wave energy to prevent beaches and cliffs from being worn away. While providing flood protection and maintaining tourist beaches, hard engineering options are often very expensive to build and maintain and can negatively impact coastal habitats and restrict public access.
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The rivalry between prominent international actors for dominance over Central Asia's hydrocarbon
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Using Mackinder's Heartland, Spykman Rimland, and Hegemonic Stability theories, examines China's role
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china’s geo economic outreach in central Asian countries and its future prospect. China is thriving in trade,
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China is seeing significant success in commerce, pipeline politics, and gaining influence on other
governments. This success may be attributed to the effective utilisation of key tools such as the Shanghai
Cooperation Organisation and the Belt and Road Economic Initiative.
Embedded machine learning-based road conditions and driving behavior monitoringIJECEIAES
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Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
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Slides from talk presenting:
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As digital technology becomes more deeply embedded in power systems, protecting the communication
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represents a multi-tiered application layer protocol extensively utilized in Supervisory Control and Data
Acquisition (SCADA)-based smart grids to facilitate real-time data gathering and control functionalities.
Robust Intrusion Detection Systems (IDS) are necessary for early threat detection and mitigation because
of the interconnection of these networks, which makes them vulnerable to a variety of cyberattacks. To
solve this issue, this paper develops a hybrid Deep Learning (DL) model specifically designed for intrusion
detection in smart grids. The proposed approach is a combination of the Convolutional Neural Network
(CNN) and the Long-Short-Term Memory algorithms (LSTM). We employed a recent intrusion detection
dataset (DNP3), which focuses on unauthorized commands and Denial of Service (DoS) cyberattacks, to
train and test our model. The results of our experiments show that our CNN-LSTM method is much better
at finding smart grid intrusions than other deep learning algorithms used for classification. In addition,
our proposed approach improves accuracy, precision, recall, and F1 score, achieving a high detection
accuracy rate of 99.50%.
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Time Division Multiplexing (TDM) is a method of transmitting multiple signals over a single communication channel by dividing the signal into many segments, each having a very short duration of time. These time slots are then allocated to different data streams, allowing multiple signals to share the same transmission medium efficiently. TDM is widely used in telecommunications and data communication systems.
### How TDM Works
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### Types of TDM
1. **Synchronous TDM**: In synchronous TDM, time slots are pre-assigned to each signal, regardless of whether the signal has data to transmit or not. This can lead to inefficiencies if some time slots remain empty due to the absence of data.
2. **Asynchronous TDM (or Statistical TDM)**: Asynchronous TDM addresses the inefficiencies of synchronous TDM by allocating time slots dynamically based on the presence of data. Time slots are assigned only when there is data to transmit, which optimizes the use of the communication channel.
### Applications of TDM
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- **Digital Audio and Video Broadcasting**: TDM is used in broadcasting systems to transmit multiple audio or video streams over a single channel, ensuring efficient use of bandwidth.
- **Computer Networks**: TDM is used in network protocols and systems to manage the transmission of data from multiple sources over a single network medium.
### Advantages of TDM
- **Efficient Use of Bandwidth**: TDM all
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the state-of-the-art Deeplabv3+ architecture with the ResNet18 backbone. The
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metrics, including an impressive global accuracy of 99.286%, a high-class accuracy of 82.191%, a mean intersection over union (IoU) of 79.900%, a weighted
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our proposed model. These findings underscore the model’s competence in precise brain tumor localization, underscoring its potential to revolutionize medical
image analysis and enhance healthcare outcomes. This research paves the way
for future exploration and optimization of advanced CNN models in medical
imaging, emphasizing addressing false positives and resource efficiency.
A review on techniques and modelling methodologies used for checking electrom...nooriasukmaningtyas
The proper function of the integrated circuit (IC) in an inhibiting electromagnetic environment has always been a serious concern throughout the decades of revolution in the world of electronics, from disjunct devices to today’s integrated circuit technology, where billions of transistors are combined on a single chip. The automotive industry and smart vehicles in particular, are confronting design issues such as being prone to electromagnetic interference (EMI). Electronic control devices calculate incorrect outputs because of EMI and sensors give misleading values which can prove fatal in case of automotives. In this paper, the authors have non exhaustively tried to review research work concerned with the investigation of EMI in ICs and prediction of this EMI using various modelling methodologies and measurement setups.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
Recycled Concrete Aggregate in Construction Part II
Design of Rubble Mound Seawall
1. 1
Design of Rubble Mound Seawall
A THESIS
Submitted in partial fulfillment of the requirement for the award of degree of
MASTER OF TECHNOLOGY IN DREDGING AND HARBOUR
ENGINEERING
BY
SHAILESH SHUKLA
Under the guidance of
K. Muthuchelvi Thangam
Scientist B
INDIAN MARITIME UNIVERSITY
VISAKHAPATNAM –530005
DATE: 06.12.2013
2. 2
DECLARATION
I hereby declare that the work described in this thesis has been carried out entirely by me in the
school of Naval Architecture and Ocean Engineering, Indian Maritime University, Visakhapatnam
campus and further state that it has not been submitted earlier wholly or in part to any other
University or Institution for the award of any degree or diploma.
SHAILESH SHUKLA
3. 3
Indian Maritime University
Visakhapatnam campus
CERTIFICATE
This is to certify that the thesis entitled “Design of Seawall “submitted by SHAILESH SHUKLA
to the Indian Maritime University for the award of the degree of Masters in Technology is a bonafide
record of project work carried out by his/her under my supervision. The contents of this thesis, in
full or in parts have not been submitted to any other institute or University for the award of any
degree or diploma.. In our opinion, the thesis is up to the standard of fulfilling the requirements of
the Master’s degree as prescribed by the regulations of this Institute.
The project has been carried out at Indian Maritime University, Visakhapatnam.
K. Muthuchelvi Thangam External Guide
Project Guide
Scientist B
SMDR
IMU, VISKHAPATNAM
Place: Visakhapatnam
Date: 06.12.2013
4. 4
ACKNOWLEDGEMENTS
First of all, I thank Almighty GOD for showering his blessings without which all my efforts would
have been in vain. I wish to express my heartfelt gratitude and indebtedness to our Director Sir for
the facilities provided to successfully carry out this project. I sincerely thank my project guide Mrs.
Muthuchelvi Thangam for her encouragement, support and sincere guidance.
Last but not least, I express my sincere thanks to my classmates and friends for their co-operation
and encouragement.
5. 5
TABLE OF CONTENTS
ACKNOWLEDGEMENTS 4
TABLE OF CONTENTS 5
LIST OF FIGURESAND TABLES 6
CHAPTER -1 INTRODUCTION 7
1.1 PROBLEM DEFINITION 7
1.2 AIM AND OBJECTIVE 7
1.3 PLAN OF WORK 8
CHAPTER -2 INTRODUCTION TO SEA WALLS 9
CHAPTER -3 DESIGN PRINCIPLES 19
CHAPTER -4 DESIGN OF SEAWALL 25
REFERENCES 31
6. 6
List of Figures
Figure Figure no. Page no.
Site location 1.1 7
Vertical and curved seawall 2.1 11
Types of seawall 2.2 11
Action of waves on seawall 2.3 12
Failure of vertical seawall 2.4 13
Location of seawall b/w high
and low water
2.5 14
Seawall with toe protection 2.6 15
Filler layer damage 2.7 15
Overtopping of waves 2.8 16
Pockets in armour layer of a
Seawall
2.9 17
Seawall layout 3.1 24
Proposed seawall location 4.1 25
Proposed area in 2003 4.2 25
Proposed area in 2013 4.3 26
Significant wave height 4.4 26
Mean wave period 4.5 27
Modal of seawall 4.6 30
List of Tables
Table content Table no. Page no.
Table for KD 3.1 21
Table for KΔ 3.2 22
Table for Total weight of the
structure
4.1 29
7. 7
CHAPTER 1
INTRODUCTION
1.1 PROBLEM DEFINITION
The Earth’s climate system is changing. All aspects of the climate are affected, including
temperature, ocean levels and rainfall patterns. The global average temperature is rising, mostly due
to increased greenhouse gas concentrations stemming from use of fossil fuels and land clearing. Sea
level rise creates an issue worldwide as it raises both the mean normal water level and the height of
waves during extreme weather events. Sea level rise increases the risks coastal communities face
from coastal hazards such as floods, storm surge, and chronic erosion. Coastal erosion is already
widespread, and there are many coasts where exceptional high tides or storm surges result in
encroachment on the shore, impinging on human activity. If the sea rises, many coasts that are
developed with infrastructure along or close to the shoreline will be unable to accommodate erosion.
An upside to the strategy is that moving seaward (and upward) can create land of high value which
can bring the investment required to cope with climate change. Sea walls are probably the second
most traditional method used in coastal management.
1.2 AIM AND OBJECTIVE
The aim of the project is to prevent destruction of property by the sea waves during high tides by the
construction of a seawall. The project involves design of 1550 m long seawall at the area where the
habitat is prone to coastal hazard here in this case is coastline near Alappuzha(Kamalapuram),
Kerala.
Fig 1.1: Site location (Source: Google Earth)
8. 8
1.4 PLAN OF WORK
Plan of work here involves choosing the right appropriate location for the construction of seawall, a
place close to habitat and infrastructure where sea is making advancement and beach is getting
depleted. Upon selection the location the requisite data of the area required for the designing of the
seawall is to be obtained. Keeping in mind the design procedure and criteria the data is processed to
design a seawall.
9. 9
CHAPTER 2
INTRODUCTION TO SEA WALLS
2.1 SEA WALLS:
2.1.1 DEFINITION
A seawall is a structure built on the beach parallel to the shoreline. Seawalls can be large or small,
high or low, and constructed of a range of materials including wood, plastic, concrete, rock,
construction rubble, steel, old cars, aluminum, rubber tires, and sandbags.
2.1.2 THE PROBLEM: COASTAL BUILDING AND SHORELINE EROSION
Shoreline erosion is the term used to describe the natural process of shoreline retreat where the
beach changes its location but retains its shape. The problem arises when shore line retreat meets
human obstacles, such as houses, highways, the seawalls placed to protect those houses and
highways. These obstacles block shoreline retreat; the beach is squeezed up against these objects,
which causes it to narrow and leads to a reduction in sand supply to adjacent beaches.
When coastal buildings or roads are threatened, the typical response is to harden the coast with a
seawall. Seawalls run parallel to the beach and can be built of concrete, wood, steel, or boulders.
Seawalls are also called bulkheads or revetments; the distinction is mainly a matter of purpose. They
are designed to halt shoreline erosion caused primarily by wave action. If seawalls are maintained,
they may temporarily hold back the ocean from encroaching on shoreline development. In spite of
their ability to hold back the ocean, when waves hit a seawall, the waves are reflected back out to
sea, taking beach sand with them and eventually causing the beach to disappear. Moreover, seawalls
can cause increased erosion at the ends of the seawall on an adjacent beach that is not walled.
2.1.3 SEAWALLS’ EFFECTIVENESS
Seawalls, if properly engineered and constructed for a particular situation, are effective at saving
beachfront property, provided the severe disadvantages they impose are acceptable. They can be
effective in protecting beachfront property from a retreating shoreline and, if high enough and strong
enough, can protect a backshore area against the onslaught of storm waves. They may retain a low
fill, but they are intended primarily to withstand and to deflect or dissipate wave energy. If a
community’s only priority is to preserve beachfront buildings then seawalls will effectively
accomplish that goal. Seawalls protect only the land immediately behind them, offering no
protection to fronting beaches.
10. 10
2.2 CLASSIFICATION OF SEAWALLS
Seawalls can be classified as:
Rigid
Flexible
Semi-flexible.
2.2.1 RIGID
A rigid seawall could be a gravity wall, sheet piling, a caisson or a concrete revetment. They have a
compact nature with a minimum plan area with the tendency not to harbour rubbish. However, they
can fail by a single large wave, toe erosion (undermining) or geotechnical instability (overturning) -
catastrophically. Mostly rigid seawalls tend to be highly reflective to incoming waves which can
result in accelerated sand loss in front of the wall during a storm, and delay beach rebuilding
following a storm. To protect the foundations of a rigid seawall from undermining, rock scour
blankets, gabions, etc. can be used. It is also possible to found the structures at depth on non-erodible
materials. However, there’s a general tendency away from rigid structures due to their cost and risk
of catastrophic failure.
2.2.2 FLEXIBLE
Flexible seawalls are constructed from quarry rock, shingle and specially manufactured concrete
units. They are not as compact as rigid seawalls but they can withstand striking deformation without
total failure occurring. The failure is progressive rather than catastrophic. Flexible seawalls are also
less reflective than rigid structures. A disadvantage is the tendency to harbour rubbish because of the
broken nature of their surface.
2.2.3 SEMI-FLEXIBLE
A combination of the characteristics of rigid seawalls and flexible seawalls are the semi-flexible
seawalls. They are compact but may not fail as easy as rigid seawalls
2.3 TYPES OF SEA WALLS:
2.3.1 CURVED SEAWALLS
Curved seawalls mirror the shape of a wave as it moves towards land. The sweeping design
dissipates the impact of the wave by deflecting it upwards, away from the bottom of the structure.
11. 11
These walls are usually made from poured concrete and are designed to reduce scour which means
the removal of sediment from around a structure, which weakens it at the base of the wall.
2.3.2 GRAVITY SEAWALLS
Seawalls that rely on heavy materials to give them stability are known as gravity seawalls. Gravity
seawalls are built in areas where strong soil runs right up to the coastline; the seawall is anchored,
using this strong soil as a foundation. These walls are susceptible to shearing around the base, a
process in which internal components of a structure move across each other as a response to stress.
Gravity seawalls usually have extra reinforcement around the base to counteract shearing.
Fig 2.1: Vertical wall and curved concrete wall
Fig 2.2: Types of seawalls (Source: seawall design construction and performance Gary Blumberg)
12. 12
2.3.3 STEEL SHEET PILE SEAWALLS
Steel sheets, interlocked and anchored deeply into the ground, are frequently used as seawalls in
areas less intensively battered by the sea. Steel sheet pile seawalls are usually anchored both into the
ground beneath them and to a bank of earth or bluff behind them. The weight of this earth acts as a
reinforcement to the wall; water retained in this bank of earth can be drained through openings in the
wall.
2.3.4 CONCRETE BLOCK AND ROCK WALLS
Walls constructed from concrete blocks and rocks mounted on a manmade slope are generally
lower-cost operations than other seawall types, but they do not last as long. A mound made of rubble
and rock is constructed, and heavy boulders made of concrete or stone are anchored into position.
The shape of the slope dissipates the force of the wave by guiding it up a gentle slope, while the
irregular boulders with gaps between them absorb the force by dividing the main wave into lots of
smaller channels.
2.4 FACTORS AFFECTING SEAWALL
For coastal protection works rigid structures should normally be avoided and the flexible structures,
which dissipate energy, should be adopted. In case of rigid structures, if unavoidable, may be
provided with slope and vertical face should in any case be avoided. The vertical face leads to the
reflection and scouring and subsequently failure of the wall. The vertical rigid retaining wall is
normally mistaken with the seawalls. However, it should be kept in mind that the function of the
seawall is to dissipate the wave energy and allow formation of beach in front of it. As such, the
sloping rubble mound seawall is the most suitable type of seawall.
Fig 2.3: Action of wave on seawall
13. 13
Fig 2.4: Failure of vertical wall
The rubble mound seawall is generally designed to consist of three layers that are core, secondary
layer and an armour layer. A minimum of two layers of stones (units) in the armour and secondary
layer is always necessary. While the thicknesses of these layers are determined by the size of stones
used, the levels including that of the core are determined based on maximum water level, design
wave height, wave run-up, permissible overtopping and method of construction.
2.4.1 POSITION OF THE SEAWALL
For locating the seawall, determination of the beach profile and the water levels are important. The
highest and the lowest water levels at the site must be known before evolving a design. The highest
water level helps in deciding the crest level while the lowest water level guides the location of the
toe. The bed slope in front of a coastal structure also has an important bearing on the extent of
damage to the structure and wave run up over the structure. With steeper slopes, damage to armour
stones is more as compared to flatbed slope. The wave run-up is also higher on steep bed slopes.
The seawall should be located in such a position that the maximum wave attack is taken by the
armour slope and the toe. The seawall, if located above the high water level contour, the waves will
break in front of the structure causing scouring and subsequent failure of the seawall. The increase in
the depths would cause higher waves to break on the coastline aggravating the erosion problem. It
should be kept in mind that seawall is for dissipating the wave energy and not merely for avoiding
inundation of the land.
14. 14
Fig 2.5: Location of Seawall between High Water & Low Water
2.4.2 UNDER DESIGN OF ARMOURS
Various factors contribute to render the armours provided in a seawall ultimately inadequate to
withstand the wave action at a given spot. Underestimation of maximum water level, incorrect
information of beach slope considered at the design stage, steeping of foreshore after the
construction of seawall, presence of a large number of smaller stones than design size (armour size
could vary from 0.75 W to 1.25 W such that 50% of the stones weigh more than W, where W is
design-size) are a few of them. In case of seawalls provided with a large percentage of undersized
armour, there has been considerable displacement and dislocation of armours. Stones having
excessively rounded corners attribute to repetitive displacements and consequent attrition and
abrasion which have been possibly compounded by poor quality stones. The stones in the lower
reaches have been excessively subjected to such forces. The displacement of the armours has
resulted in the exposure of secondary layer, which is from the section that has created small pockets
of breaches completely exposed to the fury of waves.
2.4.3 TOE PROTECTION
Toe protection is supplemental armouring of the beach or bottom surface in front of a structure,
which prevents waves from scouring and undercutting it. Factors that affect the severity of toe scour
include wave breaking (near the toe), wave run-up and backwash, wave reflection and grain size
distribution of the beach or bottom material. Toe stability is essential because failure of the toe will
generally lead to failure throughout the entire structure. Toe is generally governed by hydraulic
criteria. Scour can be caused by waves, wave induced currents or tidal currents. Design of toe
protection for seawalls must consider geo-technical as well as hydraulic factors. Using hydraulic
considerations, the toe apron should be at least twice the incident wave height for sheet-pile walls
and equal to the incident wave height for gravity walls.
15. 15
Fig 2.6: Seawall with Toe Protection
2.4.4 INADEQUATE OR NO-PROVISION OF FILTERS
Many rubble mound structures have failed due to no or inadequate provision of filter underneath. As
a consequence, the insitu soil is leached resulting in the collapse of the structure. In a typical case of
a seawall the crest of which subsided due to removal of fill material by overtopped water, there is no
proper filter between the sloping fill and the seawall. In some cases, the toe of the seawall sank over
the years due to inadequate filter and removal of insitu bed material. With the failure of the toe,
armours in the slope, which were otherwise intact, were dislodged by gravity and wave forces. These
stones occupied the toe portion and sank further due to the absence of filter. Thus the failure is
progressive and renders the seawall ineffective within a short period, if not attended promptly. In
situations such as these, the reformation of the profile to design slope alone would not be adequate.
It is necessary to provide a proper filter before reforming the section, which could be done by
dumping additional stones or retrieving some of the displaced stones.
Fig 2.7: Inadequate Filter Layer Exposed After Damage to Seawall
16. 16
2.4.5 OVERTOPPING
Underestimation of design wave or the maximum water level leads to excessive overtopping of
seawalls and eventual failure particularly when the freeboard is inadequate. Such failures also lead to
the failure of leeside slope and damage to reclamation, if any. This calls for not only proper
estimation of waver un-up and the crest level of the seawall, but for also providing proper filter
between the backfill and the seawall. It is also necessary to provide facilities for drainage of
overtopped water, which otherwise will find its way through seawall itself causing further damage.
There are instances where the reclamation fill in the lee has shown local depressions. Subsurface
fill/soil has been removed in the process of draining of overtopped water. In situations where it is not
possible to raise the level of seawall crest to avoid overtopping, it is advisable to provide a deflector
to throw a part of the overtopping water back to the seaward slope of the seawall. As mentioned
earlier, the leeside fill and the seawall core (or secondary layer) should be sandwiched by an
appropriate filter and adequate drain be provided for safe discharge of overtopped water. However,
some of the seawalls are designed as semi-submerged bunds, which allows overtopping at the higher
Water Levels. A proper care needs to be taken to prevent damage to the crest and the leeside slope
during the design of such seawalls
Fig 2.8: Overtopping of Waves over Seawall
2.4.6 ROUNDED STONES
The in-place stability of an armour unit which is distinct from the overall stability of a rubble mound
structure, but which is an essential prerequisite for the same, is dependent, interalia on the
interlocking achieved at placement of armors. In order to achieve efficient interlocking, the rock
should be sound and the individual units should have sharp edges. Blunt or round edges result in
poor interlocking and hence poor stability (lower stability factor KD), other conditions remaining the
same. Rounded stones result in lower porosity and are less efficient in dissipation of wave energy.
Lower stability factor necessitates a higher weight in a given situation, which renders the structure
17. 17
costlier. The in-place stability of such units is highly precarious and sensitive to small disturbances.
Hence such stones should not be used in rubble mound structures.
2.4.7 WEAK POCKETS
Several weak spots are often present in rubble mound structures, which maybe attributable to
reasons such as lack of supervision, quarry yielding smaller stones or deliberate attempts to dispose
of undersized stones etc. The failure thus initiated could lead to the failure of the structure as a
whole.Concentration of stones much smaller than the required armour should therefore be avoided at
any cost, lest the entire structure, however carefully executed, can become functionally ineffective.
Fig 2.9: Pockets in armour Layer of a Seawall
2.5 DESIGN PROCEDURE
The usual steps needed to design an adequate and efficient rubble mound seawall / revetments are:
Determine the water level range for the site
Determine the wave heights
Determine the beach profile after the storm condition / monsoon
Select the suitable location and configuration of the seawall
Select suitable armour to resist the design wave
Select size of the armour unit
Determine potential run-up to set the crest elevation
Determine amount of overtopping expected for low structures
Design under-drainage features if they are required
Provide for local surface runoff and overtopping runoff and make any required provisions for
other drainage facilities such as culverts and ditches
Consider end condition to avoid failure due to flanking
Design toe protection
18. 18
Design filter and under layers
Provide for firm compaction of all fill and back-fill materials. This requirement should be
included on the plans and in the specifications. Also, due allowance for compaction must be
made in the cost estimate
Develop cost estimate for each alternative.
Provision for regular maintenance and repairs of the structure.
19. 19
CHAPTER 3
DESIGN PRINCIPLES OF SEAWALL
3.1 DESIGN WATER DEPTH:
The primary factor influencing the wave conditions at the harbor site is the bathymetry in the
general vicinity of harbor.
Water depth will partly determine whether a structure is subjected to breaking, non-breaking,
or broken waves.
The maximum and minimum water depths at each section must be evaluated taking into
account the tidal range and the storm surge effect.
3.2 DESIGN WAVE:
The most important single factor controlling the design of seawall will be the “Design wave”.
The design wave must be so chosen that the seawall during its construction and throughout
its intended service life has a sufficiently low probability of failure both in terms of
unacceptable damage and collapse.
Shore protection manual (1984) specifies that H1/10 (average of the highest one-tenth of the
waves) should be used as the design wave height for rubble mound seawall instead of
H1/3(significant wave height) as recommended in earlier editions.
3.3 CREST ELEVATION:
The crest level is very important for the total cost, since the total volume of the seawall is
approximately proportional to the second power of the total height of the seawall.
The crest level should be as low as permitted by the functional requirements and stability of
armor units on crest and the lee side. Reduced crest level would mean overtopping when high
waves and high water levels occur. Whether overtopping will occur or not will depend on the
wave run-up and for rubble slopes.
3.4 SLOPE ANGLE:
Side slopes are generally as steep as possible to minimize the volume of core material and to
reduce the reach of cranes working from the crest.
20. 20
However it may be possible to develop a less steep slope if the cranes operate from a barge.
Slopes are typically within the range 1V:1.5H to 1V:3H and influence the amount of
interaction between armor units.
As the angle increases, the contribution to stability from friction and interlocking also
increases due to the squeezing or increase in slope-parallel forces applied by adjacent units.
There is however a corresponding decrease in the slope-perpendicular component of self-
weights. This implies optimum slope angles for maximum interaction and stability.
3.5 WEIGHT OF ARMOR UNIT:
Hudson (1959) considered the stability of an individual armor unit subjected to wave action
and assumed that the disturbing forces could be type of drag and lift caused by the wave
motion which tends to move the armor unit.
The stabilizing forces were considered to be mainly the submerged weight of each unit.
3
3
1 cot
HaW
K SG
D
W = weight of individual armour unit in primary cover layer (t).
a = Unit weight of armor unit (t/m3
).
H = design wave height (m).
SG = Specific gravity of armor unit relative to the water at the structure site.
α = Angle of structure slope measured from horizontal in degrees.
KD = Stability coefficient that varies primarily with the shape of the armor unit.
21. 21
Table 3.1: Table for KD value (Source: EM 1110-2-1614)
3.6 CREST WIDTH:
The crest width depends greatly on the degree of overtopping permitted. Where there is no
overtopping, crest width is not critical.
Shore protection manual (1984) recommends as a general guide that the minimum crest width
should equal the combined widths of three armor units.
1/3
WB nK
a
B = Crest width
n = number of stones or armor units (n=3 is recommended).
K∆ = layer coefficient.
W = weight of primary armor unit.
a = unit weight of armor unit.
22. 22
3.7 THICKNESS OF ARMOR LAYER:
The thickness of the cover and under layers required can be determined from the following
formulae:
1/3
Wr nK
a
r = Average layer thickness.
n = number of armor units in thickness comprising the cover layer.
K∆ = Layer thickness.
W = weight of individual armor unit.
a = unit weight of armor unit.
Fig 3.2: Table for KΔ(Source: EM1110-2-1614)
3.8 SECONDARY COVER LAYER:
The purpose of the secondary core layer is to prevent core material from being washed out
through the voids of the primary armor layer and at the same time provide a good foundation
for the heavier units of the primary armor layer.
23. 23
The secondary cover layer also should act as a temporary protection to the core before
primary armor is laid.
Shore protection manual recommends the stone sizes in the secondary layers to be W/10 to
W/15 and a minimum thickness corresponding to two stone layers.
3.9 CORE:
The purpose of the core is following:
To form a substantial portion of the total volume of the rubble mound seawall in order to
utilize the quarry run which is available as a byproduct of the quarrying for secondary and
primary armor stones.
To provide a satisfactory foundation for the secondary and primary armor layers, and for any
cap stone or cap wall on top.
To provide a relatively impermeable barrier to the transmission of wave energy, and
To form a suitable working platform from which the secondary and primary armor layers can
be constructed.
The weight of core will vary from W/100 to W/400. A highly impermeable core may prevent
wave transmission through the structure but because of pore pressure build up, is likely to
have an adverse effect on the stability of the cover layers.
The influence of core permeability on the wave transmission and stability suggest that a
densely packed but fairly permeable core, a limit may be specified on the minimum size of
the material to be used. This is also necessary to avoid wash out of core material.
3.10 BOTTOM ELEVATION OF PRIMARY COVER LAYER:
The armor units in the cover layer should be extended down slope to an elevation below
minimum still water level equal to the design wave height.
3.11 TOE BERM:
Seawalls exposed to breaking waves should have their primary cover layers supported by a
quarry stone berm.
The quarry stone in the toe berm should be of weight W/10 to W/15. The width of the toe
berm must be such as to hold at least three stones and thickness must be such as to have two
stone layers. The toe berm is generally intended to provide safety against foundation failure
and hydraulic stability of the structure.
24. 24
3.12 BEDDING LAYERS OR FILTER LAYERS:
Wave action against rubble mound seawalls creates enough turbulence within the structure
and in the underlying sea bed that may result in sucking of soil into the structure. This may
cause settlement of structure.
A filter blanket or a bedding layer is a good precaution against such settlement.
Geotextiles filters may also be used. In case of clays and silts, it will be necessary to provide
a coarse sand layer first before placing the filter blanket or bedding layer.
The bedding layers must extend well beyond the toe of the structure.
The weight of filter layer varies from W/1000 to W/6000.
Grain size of sand used is 100 mm.
Fig: 3.1: Seawall layout (Source: CWPRS Technical Memoranda for Seawall)
25. 25
CHAPTER 4
DESIGN OF RUBBLE MOUND SEAWALL
4.1.1 Length and location of Seawall
Fig: 4.1: Proposed seawall location
Length of seawall is: 1.55 Km
Latitude and Longitude: ’ . ” ’ . ” E
Location: Kamalapuram / Alappuzha / Kerala / India.
4.1.2 Criteria for Site Selection:
The area near Kamalapuram has been selected for the construction of seawall because of the gradual
erosion along the coast. The following has been shown with the help of satellite imagery below.
Fig 4.2: Proposed area in 2003
26. 26
Fig 4.3: Proposed area in 2013
4.2 Determining significant wave height and wave period
Significant wave height:
Fig 4.4: Significant wave height (Source: Panoply software data analysis)
The wave height obtained is 1.524 m. The significant wave height is obtained by analyzing
cumulative data from 2003 to 2013.
27. 27
Wave Period:
Fig 4.5: Mean Wave Period (Source: Panoply software data analysis)
The mean wave period is 7 sec. The wave is determining by analyzing data from 2003 to 2013.
4.3 DESIGN PROCEDURE:
Design conditions:
Depth of water (d) = 3.224 m
Time period of the wave approaching the
seawall (T) (assumed)
= 7.468 sec
Armor unit = Rough quarry stone
Unit weight of quarry stone = 2.65 t/m3
Structure slope = 1 in 1.5
Shape = Symmetrical
28. 28
Weight of armor unit:
3
3
1 cot
HaW
K SG
D
KD = 2 (for rough quarry stone)
a = 2.65 t/ m3
w = 1.025 t/m3
α = 1 in 1.5
Cot α = 1.5
H = 2.524 m
Crest width:
Minimum crest width should equal the combined width of 3 armor units.
n (number of armor units) = 3
1/3
WB nK
a
B = 3.31 m
Armor layer thickness:
1/3
Wr nK
a
n = 2
Armor layer thickness (r) = 2.2068 m
W = 3.56 T
29. 29
Secondary cover layer:
Thickness of secondary layer is same as armor layer and weight varies from 0.356 T to 0.237T.
Quarry stones are used as secondary layer.
Core layer:
The weight of core layer varies from 0.0356 T to 0.0089 T.
Gravel is the material used here.
Filter layer/ bedding layer:
The weight of filter layer varies from 0.00356 T to 0.000593 T and sand size of 100 mm is used.
Toe berm:
The weight of toe berm varies from 0.356 T to 0.237T.
Width = 2xHs = 3.05 m
Depth = 0.4 d = 1.29 m
Height of the structure = Thickness of Armour layer + Thickness of Under layer + Depth of Toe
berm + Thickness of Bedding layer
= 2.2068 + 2.2068 + 1.2896 + 1
= 6.7 m
Table 4.1: Table for Total weight of the structure
NAME OF
LAYER
AREA ( M
2
) UNIT WEIGHT
(T)
LENGTH (M) TOTAL WEIGHT
(T)
(AREA*WT*L)
Armour Layer 33.0131 3.56 1550 182,166.286
Under Layer 20.6802 0.356 1550 11,411.334
Core Layer 6.3770 0.0356 1550 351.88
Toe Berm 2*3.9345 = 7.869 0.356 1550 4342.114
Filter Layer 30 0.00356 1550 165.54
Weight of the structure = 198,437.15 T
31. 31
Reference:
Technical memorandum on guidelines for design and construction of seawalls, May, 2010,
Central Water & Power Research Station, Pune.
Design of Coastal Revetments,Seawalls, and Bulkheads, EM 1110-2-1614
Evaluating theCondition of Seawalls/Bulkheads -Coastal Systems International, Inc.
European Centre for Medium-Range Weather Forecasts (ECMWF)
http://www.giss.nasa.gov/tools/panoply/
Harbour and Coastal Engineering S. Narasimhan & S. Kathiroli.