1) Nile Research Institute conducted a study of local scour at the El-Minia Bridge piers in Egypt. Field investigations found that the river bed had changed around the bridge piers, with a maximum local scour depth of 4.6 meters occurring between 1982 and 2002.
2) A computer model (HEC-RAS) was used to simulate local scour for a flow of 180 cubic meters per second. The model results showed the contraction and pier scour depths expected for this flow condition. Maximum local scour depths were computed for each bridge pier.
3) Studying local scour is important for evaluating scour risks and impacts to bridge foundations, and for proposing mitigation measures to
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.
Creep is the gradual longitudinal movement of rails in the direction of dominant traffic over time. It is caused by various factors like wave action from moving loads, percussion from wheel impacts at joints, drag from locomotive wheels, and thermal expansion/contraction. Creep can be measured using creep indicators and causes issues like disturbed track geometry and signaling. Sections prone to high creep include grade transitions, structures, and points/crossings. Preventative methods include pulling rails back periodically, using anchors to fix rails to sleepers, and installing steel sleepers for increased stiffness.
This document provides guidelines for bridge design in the Public Works Department. It introduces the contents and chapters, which cover aspects of bridge design, components, innovative structures, preparation of bridge projects, and other topics. The guidelines are intended to help engineers understand the department's practices for bridge design. The second edition was revised with new chapters and information to aid both new and experienced engineers.
The document discusses different types of pavements used for highways. It describes flexible pavements which transmit wheel loads through grain-to-grain contact and consist of multiple layers including the surface course, binder course, base course, and sub-base course. Rigid pavements have sufficient strength to distribute loads over a wider area and typically consist of concrete over a single granular or stabilized layer. The document also covers pavement materials like soils, aggregates, and asphalt concrete and tests used to evaluate soil strength properties important for pavement design like the California Bearing Ratio test.
Hydraulic failures .... 40%
Seepage failures…….. 30%
Structural failures .... 30%
(1) Overtopping
(2) Erosion of u/s slope by waves
(3) Erosion of d/s slope by wind and rain
(4) Erosion of d/s toe
(5) Frost action
(1) Overtopping = the design flood is under estimated.
spillway capacity is not adequet
spillway gates are not properly operated
free board is not sufficient
excessive settlement of the foundation and dam
(2) Erosion of u/s slope by waves = The waves developed near the top water surface due to the winds, try to notch out the soil from the upstream face and may even, sometimes, cause the slip of the upstream slope.
Upstream stone pitching or riprap should, therefore, be provided to avoid such failures.
(3) Erosion of d/s slope by wind and rain = The rainwater flowing down the slope; may result in the formation of 'gullies' on the downstream slope thus damaging the dam which may generally lead to partial failure of the dam or in some cases it may cause complete failure of the dam.
Erosion of d/s toe : = Toe erosion may occur due to two reasons :
erosion due to tail water
erosion due to cross currents that may come from spillway buckets.
Frost action : = If the earth dam is located at a place where the temperature falls below the freezing point, frost may form in the pores of the soil in the earth dam.
When there is heaving, the cracks may form in the soil. This may lead to dangerous seepage and consequent failure.
Seepage failures : = Seepage failures may occur due to the following causes :
(1) Piping through the foundation
(2) Piping through the dam
(3) Sloughing of d/s toe
Structural failures :=
Structural failures in earth dams are generally shear failures leading to sliding of the tents or the foundations.
(1) u/s and d/s slope failures due to construction pore pressures
(2) u/s slope failure due to sudden drawdown
(3) D/s slope failure due to steady seepage
(4) Foundation slide due to spontaneous liquefaction
(5) Failure due to earthquake
(6) Failure by spreading
(7) Slope protection failures
(8) Failure due to damage caused by borrowing animals
(9) Failure due to holes caused by leaching of water soluable salts
Criteria for safe Design of Earth Dam :
Section of an Earth Dam :
The design of an earth dam essentially consists of determining such a cross section
the dam which when constructed with the available materials will fulfill its required
tion with adequate safety. Thus there are two aspects of the design of an earth dam.
Canal fall- necessity and location- types of falls- Cross regulator and
distributory head regulator- their functions, Silt control devices, Canal
escapes- types of escapes.
This document discusses different types of canal lining materials and their advantages. It states that lining canals reduces water losses through seepage and prevents waterlogging of adjacent lands. It allows for smaller canal dimensions since lined canals have lower resistance to flow. Lining also reduces maintenance needs like silt removal and bank repairs. Common lining materials described include cement concrete, shotcrete, precast concrete, brick and various earth linings. Cement concrete lining provides excellent hydraulic properties but has high costs. Shotcrete and cement mortar linings use large amounts of cement. Brick lining allows for easy repair and is hydraulically efficient. Lining improves water conservation and irrigation capacity but requires heavy initial investment.
Canal falls are structures constructed across canals to lower the bed level to maintain the designed slope when there is a change in ground level. The main types of canal falls are ogee falls, stepped falls, vertical falls, rapid falls, and straight glacis falls. Canal escapes are side channels that remove surplus water from canals into natural drains. The main types are surplus escapes, tail escapes, and scouring escapes. Cross drainage works include structures like aqueducts and siphon aqueducts to allow canals to pass over drainages when their bed levels differ.
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.
Creep is the gradual longitudinal movement of rails in the direction of dominant traffic over time. It is caused by various factors like wave action from moving loads, percussion from wheel impacts at joints, drag from locomotive wheels, and thermal expansion/contraction. Creep can be measured using creep indicators and causes issues like disturbed track geometry and signaling. Sections prone to high creep include grade transitions, structures, and points/crossings. Preventative methods include pulling rails back periodically, using anchors to fix rails to sleepers, and installing steel sleepers for increased stiffness.
This document provides guidelines for bridge design in the Public Works Department. It introduces the contents and chapters, which cover aspects of bridge design, components, innovative structures, preparation of bridge projects, and other topics. The guidelines are intended to help engineers understand the department's practices for bridge design. The second edition was revised with new chapters and information to aid both new and experienced engineers.
The document discusses different types of pavements used for highways. It describes flexible pavements which transmit wheel loads through grain-to-grain contact and consist of multiple layers including the surface course, binder course, base course, and sub-base course. Rigid pavements have sufficient strength to distribute loads over a wider area and typically consist of concrete over a single granular or stabilized layer. The document also covers pavement materials like soils, aggregates, and asphalt concrete and tests used to evaluate soil strength properties important for pavement design like the California Bearing Ratio test.
Hydraulic failures .... 40%
Seepage failures…….. 30%
Structural failures .... 30%
(1) Overtopping
(2) Erosion of u/s slope by waves
(3) Erosion of d/s slope by wind and rain
(4) Erosion of d/s toe
(5) Frost action
(1) Overtopping = the design flood is under estimated.
spillway capacity is not adequet
spillway gates are not properly operated
free board is not sufficient
excessive settlement of the foundation and dam
(2) Erosion of u/s slope by waves = The waves developed near the top water surface due to the winds, try to notch out the soil from the upstream face and may even, sometimes, cause the slip of the upstream slope.
Upstream stone pitching or riprap should, therefore, be provided to avoid such failures.
(3) Erosion of d/s slope by wind and rain = The rainwater flowing down the slope; may result in the formation of 'gullies' on the downstream slope thus damaging the dam which may generally lead to partial failure of the dam or in some cases it may cause complete failure of the dam.
Erosion of d/s toe : = Toe erosion may occur due to two reasons :
erosion due to tail water
erosion due to cross currents that may come from spillway buckets.
Frost action : = If the earth dam is located at a place where the temperature falls below the freezing point, frost may form in the pores of the soil in the earth dam.
When there is heaving, the cracks may form in the soil. This may lead to dangerous seepage and consequent failure.
Seepage failures : = Seepage failures may occur due to the following causes :
(1) Piping through the foundation
(2) Piping through the dam
(3) Sloughing of d/s toe
Structural failures :=
Structural failures in earth dams are generally shear failures leading to sliding of the tents or the foundations.
(1) u/s and d/s slope failures due to construction pore pressures
(2) u/s slope failure due to sudden drawdown
(3) D/s slope failure due to steady seepage
(4) Foundation slide due to spontaneous liquefaction
(5) Failure due to earthquake
(6) Failure by spreading
(7) Slope protection failures
(8) Failure due to damage caused by borrowing animals
(9) Failure due to holes caused by leaching of water soluable salts
Criteria for safe Design of Earth Dam :
Section of an Earth Dam :
The design of an earth dam essentially consists of determining such a cross section
the dam which when constructed with the available materials will fulfill its required
tion with adequate safety. Thus there are two aspects of the design of an earth dam.
Canal fall- necessity and location- types of falls- Cross regulator and
distributory head regulator- their functions, Silt control devices, Canal
escapes- types of escapes.
This document discusses different types of canal lining materials and their advantages. It states that lining canals reduces water losses through seepage and prevents waterlogging of adjacent lands. It allows for smaller canal dimensions since lined canals have lower resistance to flow. Lining also reduces maintenance needs like silt removal and bank repairs. Common lining materials described include cement concrete, shotcrete, precast concrete, brick and various earth linings. Cement concrete lining provides excellent hydraulic properties but has high costs. Shotcrete and cement mortar linings use large amounts of cement. Brick lining allows for easy repair and is hydraulically efficient. Lining improves water conservation and irrigation capacity but requires heavy initial investment.
Canal falls are structures constructed across canals to lower the bed level to maintain the designed slope when there is a change in ground level. The main types of canal falls are ogee falls, stepped falls, vertical falls, rapid falls, and straight glacis falls. Canal escapes are side channels that remove surplus water from canals into natural drains. The main types are surplus escapes, tail escapes, and scouring escapes. Cross drainage works include structures like aqueducts and siphon aqueducts to allow canals to pass over drainages when their bed levels differ.
Permanent Way of Railway & Components ?(part -1,2,3,4,5)RAMPRASAD KUMAWAT
Permanent Way Components: , Selection of Alignment, Ideal Permanent Ways and Cross-sections in different conditions, Salient Features and types of Components viz.
Rails, Sleepers, Ballast, Rail Fastenings.
Types and Selection of Gauges
This document discusses embankment dams. Embankment dams are made of earth and rock fragments and come in different types like rolled fill and hydraulic fill dams. The components of an embankment dam include the foundation, casing, and core. The core acts as an impermeable barrier. Embankment dam failures can be hydraulic from overtopping, wave action, toe erosion or gullying. They can also be from seepage type failures like piping or sloughing. Piping is caused by continuous seepage flow through the dam body or foundation.
The document outlines the details of Nagpur's first 20-year road plan presented by a civil engineer. It included 5 categories for road design, recommendations on geometric design, bridges, and highway organizations. The plan aimed to provide 2 lakh km of surfaced roads and the remaining unsurfaced by 1963, with a total road length of 532,700 km and density of 16 km per 1,000 sq km. It was based on a star and grid pattern for the road network, considering existing roads and obligatory points. The farthest point from a metalled road would be 8 km in developed/agricultural areas and 32 km in non-agricultural areas. 15% clearance was provided for development. The
The document describes the components and purposes of weirs and barrages. Weirs and barrages are solid structures built across rivers to raise water levels and divert water into canals. The main differences are that barrages use gates to regulate flow, while weirs use crest height. Barrages are more expensive than weirs. The structures are used to control water levels and flows, prevent flooding, divert water, and train rivers to reduce impacts on canal headworks. Key components include the main body, divide wall, under sluices, fish ladder, sheet piles, apron, and river training works.
Types- selection of the suitable site for the diversion headwork components
of diversion headwork- Causes of failure of structure on pervious foundation- Khosla’s theory- Design of concrete sloping
glacis weir.
This document discusses theories for designing weirs on permeable foundations to prevent failures from seepage. It describes Bligh's creep theory, Lane's weighted creep theory, and Khosla's theory. Bligh's theory calculates creep length and floor thickness but does not distinguish horizontal from vertical creep. Lane's theory assigns higher weight to vertical creep. Khosla's theory accounts for pressure distributions and recommends cut-offs and aprons. It is commonly used but requires corrections for floor thickness, pile interference, and slope. Inverted filters and launching aprons are also discussed.
This document discusses canal irrigation and diversion head works. It begins by defining a canal as an artificial channel constructed to carry water from a river, tank, or reservoir to fields. Canals are classified based on their source of supply, financial output, function, and boundary surface. Unlined canals are designed using either Kennedy's Theory from 1895 or Lacey's Theory from 1939. Kennedy's Theory is based on experiments observing eddy formation and silt suspension. Lacey's Theory considers drawbacks of Kennedy's Theory and designs for regime conditions. Both theories use empirical formulae and have limitations in achieving true regime conditions and defining characteristics precisely.
Cross drainage works are hydraulic structures built where canals intersect natural streams or drainage in order to prevent mixing of canal and drainage waters. There are three main types of cross drainage works depending on the relative bed levels of the canal and drainage: 1) where the canal passes over the drainage (e.g. aqueduct or siphon aqueduct), 2) where the drainage passes over the canal (e.g. super passage or siphon super passage), and 3) where the canal and drainage intersect at the same level (e.g. level crossing or inlet and outlet). The appropriate type of structure is selected based on factors like relative bed levels, foundation conditions, cost, and hydraulic requirements.
Infrastructure for water resource development_ Sushil Kumar (NWA)_2011India Water Portal
Dams are classified based on their use, material, and size. The three main types are storage dams, diversion dams, and hydroelectric dams. Storage dams create reservoirs and are the most common type for water storage. Diversion dams raise water levels to divert water into conveyance systems. Infrastructure for water resources includes dams, barrages, weirs, canals, canal regulation works, and cross drainage works. Hydroelectric power plants have components like intake structures, penstocks, power houses with turbines, and tailraces.
The document provides an overview of the different types of bridges based on various classification categories. Bridges can be classified based on their form of superstructure, construction materials used, usage, interspan relation, service period, movement of parts, navigation facility, position of floor, submergence condition, level of crossing, span, and alignment. Common types of bridges include beam, truss, arch, tied arch, suspension, and cable-stayed bridges.
This document discusses how water surface profiles within culverts are classified in two ways: 1) Hydraulic Slope, which is based on the culvert bottom slope and the relationship between critical depth and normal depth, and 2) Hydraulic Curve, which describes the shape of the water surface profile based on the Hydraulic Slope classification and the actual flow depth relative to critical and normal depths. There are five Hydraulic Slope classifications - Adverse, Horizontal, Critical, Mild, and Steep - which can change as flows increase. The three Hydraulic Curve classifications - Type 1, 2, and 3 - indicate whether flow is subcritical or supercritical.
This document provides an overview of transportation engineering and different modes of transportation. It discusses highways, railways, airways, and waterways in detail. For highways, it covers their historical development in India including key committees and acts that helped develop the road network like the Jayakar Committee, Central Road Fund, and Motor Vehicles Act. It also discusses classification of highways in India based on various factors.
This document discusses different types of canal outlets used to release water from distributing channels into watercourses. It describes non-modular, semi-modular, and modular outlets. Non-modular outlets discharge based on water level differences, while modular outlets discharge independently of water levels. Semi-modular outlets discharge depending on the channel water level but not the watercourse level. Specific outlet types are also defined, such as pipe outlets, open sluice, and Gibbs, Khanna, and Foote rigid modules. Discharge equations for different outlet types are provided.
Topics:
1. Types of Gravity Dam
2. Forces Acting on a Gravity Dam
3. Causes of failure of Gravity Dam
4. Elementary Profile of Gravity Dam
5. Practical Profile of Gravity Dam
6. Limiting height of Gravity Dam
7. Drainage and Inspection Galleries
Railway Engineering - Geometric design of trackMani Vel
This document discusses the importance of proper geometric design of railway tracks. It outlines key considerations for geometric design including gradients, curvature, and track alignment. Proper design is needed to ensure safe train operation at maximum speeds and loads. Specific geometric design elements are described, such as ruling gradients, helper gradients, momentum gradients, and standards for station yard gradients. Grade compensation is also outlined, where steeper gradients are allowed on curved tracks compared to straight tracks.
Present slideshow provides brief introductory part of various Intake Structures. This is useful for Environmental Engineering Students, faculties and learners.
The document discusses and compares the theories of Kennedy and Lacey regarding stable channel design for irrigation canals. Kennedy's theory is based on the concept of critical velocity to prevent silting, while Lacey's regime theory differentiates between true, initial, and final regimes and introduces the concept of a silt factor. The key differences between the two theories are also summarized.
This document discusses sight distance, which refers to the length of road visible to a driver at any time. It defines three types of sight distance - stopping sight distance, overtaking sight distance, and intersection sight distance. Stopping sight distance is the minimum distance required for a driver to stop safely without collision. Overtaking sight distance is the minimum distance required for a vehicle to safely pass another traveling in the opposite direction. Intersection sight distance allows drivers to see any hazards and stop if needed when approaching an intersection. The computation of sight distances depends on factors like reaction time, vehicle speed, braking efficiency, road gradient, and the speeds of multiple vehicles in overtaking situations.
Design and construction of well foundationsDar Hilal
Well foundations are commonly used for transferring heavy loads to deep soil strata for bridges. They have a large cross-sectional area and can take large vertical and horizontal loads. Designing well foundations involves determining the depth, shape, size, and type based on factors like minimum grip length and permissible base pressures. Common well foundation types include open, box, and pneumatic caissons. Precautions during construction like uniform dredging are important to avoid tilting and shifts. Well foundations are a low-cost and trusted option for bridge construction due to their high success rates and long life spans, though sinking can be time consuming.
EXPERIMENTAL STUDY OF BRIDGE PIER SHAPE TO MINIMIZE LOCAL SCOURIAEME Publication
The study of local scour around bridge piers is very important for safe design of piers and other hydraulic structures. In this study, shape of pier is the main concern with three different velocities (0.18, 0.25, and 0.3) m/sec and other parameters like flow depth, bed material and etc. are remain same for all experiments. The experiments were conducted using laboratory flume, operated under the clear water condition using sand as a bed material. The test program was done on ten different shapes, Circular, Rectangular, Octagonal, Chamfered, Hexagonal, Elliptical, Sharp, Joukowsky, Oblong, streamline. were used to investigate the effect of the bridge pier's shape on local scour to conclude the optimal shape that gives minimum depth of scour. Comparison of results show that scour at upstream is directly proportional to exposed area of upstream nose of pier.
This document summarizes several projects where Seabed Scour Control Systems Ltd. provided their weighted frond mats to protect offshore infrastructure from scouring. It describes projects in locations like the Andaman Sea, North Sea, Indonesia, Guyana, Europe, China, and the Norfolk Broads where their mats were installed around pipelines, platforms, wind turbine foundations, and river banks to rectify existing scour and provide long-term scour protection. Feedback from customers on the various projects indicated the mats successfully arrested scour and protected the infrastructure as intended.
Permanent Way of Railway & Components ?(part -1,2,3,4,5)RAMPRASAD KUMAWAT
Permanent Way Components: , Selection of Alignment, Ideal Permanent Ways and Cross-sections in different conditions, Salient Features and types of Components viz.
Rails, Sleepers, Ballast, Rail Fastenings.
Types and Selection of Gauges
This document discusses embankment dams. Embankment dams are made of earth and rock fragments and come in different types like rolled fill and hydraulic fill dams. The components of an embankment dam include the foundation, casing, and core. The core acts as an impermeable barrier. Embankment dam failures can be hydraulic from overtopping, wave action, toe erosion or gullying. They can also be from seepage type failures like piping or sloughing. Piping is caused by continuous seepage flow through the dam body or foundation.
The document outlines the details of Nagpur's first 20-year road plan presented by a civil engineer. It included 5 categories for road design, recommendations on geometric design, bridges, and highway organizations. The plan aimed to provide 2 lakh km of surfaced roads and the remaining unsurfaced by 1963, with a total road length of 532,700 km and density of 16 km per 1,000 sq km. It was based on a star and grid pattern for the road network, considering existing roads and obligatory points. The farthest point from a metalled road would be 8 km in developed/agricultural areas and 32 km in non-agricultural areas. 15% clearance was provided for development. The
The document describes the components and purposes of weirs and barrages. Weirs and barrages are solid structures built across rivers to raise water levels and divert water into canals. The main differences are that barrages use gates to regulate flow, while weirs use crest height. Barrages are more expensive than weirs. The structures are used to control water levels and flows, prevent flooding, divert water, and train rivers to reduce impacts on canal headworks. Key components include the main body, divide wall, under sluices, fish ladder, sheet piles, apron, and river training works.
Types- selection of the suitable site for the diversion headwork components
of diversion headwork- Causes of failure of structure on pervious foundation- Khosla’s theory- Design of concrete sloping
glacis weir.
This document discusses theories for designing weirs on permeable foundations to prevent failures from seepage. It describes Bligh's creep theory, Lane's weighted creep theory, and Khosla's theory. Bligh's theory calculates creep length and floor thickness but does not distinguish horizontal from vertical creep. Lane's theory assigns higher weight to vertical creep. Khosla's theory accounts for pressure distributions and recommends cut-offs and aprons. It is commonly used but requires corrections for floor thickness, pile interference, and slope. Inverted filters and launching aprons are also discussed.
This document discusses canal irrigation and diversion head works. It begins by defining a canal as an artificial channel constructed to carry water from a river, tank, or reservoir to fields. Canals are classified based on their source of supply, financial output, function, and boundary surface. Unlined canals are designed using either Kennedy's Theory from 1895 or Lacey's Theory from 1939. Kennedy's Theory is based on experiments observing eddy formation and silt suspension. Lacey's Theory considers drawbacks of Kennedy's Theory and designs for regime conditions. Both theories use empirical formulae and have limitations in achieving true regime conditions and defining characteristics precisely.
Cross drainage works are hydraulic structures built where canals intersect natural streams or drainage in order to prevent mixing of canal and drainage waters. There are three main types of cross drainage works depending on the relative bed levels of the canal and drainage: 1) where the canal passes over the drainage (e.g. aqueduct or siphon aqueduct), 2) where the drainage passes over the canal (e.g. super passage or siphon super passage), and 3) where the canal and drainage intersect at the same level (e.g. level crossing or inlet and outlet). The appropriate type of structure is selected based on factors like relative bed levels, foundation conditions, cost, and hydraulic requirements.
Infrastructure for water resource development_ Sushil Kumar (NWA)_2011India Water Portal
Dams are classified based on their use, material, and size. The three main types are storage dams, diversion dams, and hydroelectric dams. Storage dams create reservoirs and are the most common type for water storage. Diversion dams raise water levels to divert water into conveyance systems. Infrastructure for water resources includes dams, barrages, weirs, canals, canal regulation works, and cross drainage works. Hydroelectric power plants have components like intake structures, penstocks, power houses with turbines, and tailraces.
The document provides an overview of the different types of bridges based on various classification categories. Bridges can be classified based on their form of superstructure, construction materials used, usage, interspan relation, service period, movement of parts, navigation facility, position of floor, submergence condition, level of crossing, span, and alignment. Common types of bridges include beam, truss, arch, tied arch, suspension, and cable-stayed bridges.
This document discusses how water surface profiles within culverts are classified in two ways: 1) Hydraulic Slope, which is based on the culvert bottom slope and the relationship between critical depth and normal depth, and 2) Hydraulic Curve, which describes the shape of the water surface profile based on the Hydraulic Slope classification and the actual flow depth relative to critical and normal depths. There are five Hydraulic Slope classifications - Adverse, Horizontal, Critical, Mild, and Steep - which can change as flows increase. The three Hydraulic Curve classifications - Type 1, 2, and 3 - indicate whether flow is subcritical or supercritical.
This document provides an overview of transportation engineering and different modes of transportation. It discusses highways, railways, airways, and waterways in detail. For highways, it covers their historical development in India including key committees and acts that helped develop the road network like the Jayakar Committee, Central Road Fund, and Motor Vehicles Act. It also discusses classification of highways in India based on various factors.
This document discusses different types of canal outlets used to release water from distributing channels into watercourses. It describes non-modular, semi-modular, and modular outlets. Non-modular outlets discharge based on water level differences, while modular outlets discharge independently of water levels. Semi-modular outlets discharge depending on the channel water level but not the watercourse level. Specific outlet types are also defined, such as pipe outlets, open sluice, and Gibbs, Khanna, and Foote rigid modules. Discharge equations for different outlet types are provided.
Topics:
1. Types of Gravity Dam
2. Forces Acting on a Gravity Dam
3. Causes of failure of Gravity Dam
4. Elementary Profile of Gravity Dam
5. Practical Profile of Gravity Dam
6. Limiting height of Gravity Dam
7. Drainage and Inspection Galleries
Railway Engineering - Geometric design of trackMani Vel
This document discusses the importance of proper geometric design of railway tracks. It outlines key considerations for geometric design including gradients, curvature, and track alignment. Proper design is needed to ensure safe train operation at maximum speeds and loads. Specific geometric design elements are described, such as ruling gradients, helper gradients, momentum gradients, and standards for station yard gradients. Grade compensation is also outlined, where steeper gradients are allowed on curved tracks compared to straight tracks.
Present slideshow provides brief introductory part of various Intake Structures. This is useful for Environmental Engineering Students, faculties and learners.
The document discusses and compares the theories of Kennedy and Lacey regarding stable channel design for irrigation canals. Kennedy's theory is based on the concept of critical velocity to prevent silting, while Lacey's regime theory differentiates between true, initial, and final regimes and introduces the concept of a silt factor. The key differences between the two theories are also summarized.
This document discusses sight distance, which refers to the length of road visible to a driver at any time. It defines three types of sight distance - stopping sight distance, overtaking sight distance, and intersection sight distance. Stopping sight distance is the minimum distance required for a driver to stop safely without collision. Overtaking sight distance is the minimum distance required for a vehicle to safely pass another traveling in the opposite direction. Intersection sight distance allows drivers to see any hazards and stop if needed when approaching an intersection. The computation of sight distances depends on factors like reaction time, vehicle speed, braking efficiency, road gradient, and the speeds of multiple vehicles in overtaking situations.
Design and construction of well foundationsDar Hilal
Well foundations are commonly used for transferring heavy loads to deep soil strata for bridges. They have a large cross-sectional area and can take large vertical and horizontal loads. Designing well foundations involves determining the depth, shape, size, and type based on factors like minimum grip length and permissible base pressures. Common well foundation types include open, box, and pneumatic caissons. Precautions during construction like uniform dredging are important to avoid tilting and shifts. Well foundations are a low-cost and trusted option for bridge construction due to their high success rates and long life spans, though sinking can be time consuming.
EXPERIMENTAL STUDY OF BRIDGE PIER SHAPE TO MINIMIZE LOCAL SCOURIAEME Publication
The study of local scour around bridge piers is very important for safe design of piers and other hydraulic structures. In this study, shape of pier is the main concern with three different velocities (0.18, 0.25, and 0.3) m/sec and other parameters like flow depth, bed material and etc. are remain same for all experiments. The experiments were conducted using laboratory flume, operated under the clear water condition using sand as a bed material. The test program was done on ten different shapes, Circular, Rectangular, Octagonal, Chamfered, Hexagonal, Elliptical, Sharp, Joukowsky, Oblong, streamline. were used to investigate the effect of the bridge pier's shape on local scour to conclude the optimal shape that gives minimum depth of scour. Comparison of results show that scour at upstream is directly proportional to exposed area of upstream nose of pier.
This document summarizes several projects where Seabed Scour Control Systems Ltd. provided their weighted frond mats to protect offshore infrastructure from scouring. It describes projects in locations like the Andaman Sea, North Sea, Indonesia, Guyana, Europe, China, and the Norfolk Broads where their mats were installed around pipelines, platforms, wind turbine foundations, and river banks to rectify existing scour and provide long-term scour protection. Feedback from customers on the various projects indicated the mats successfully arrested scour and protected the infrastructure as intended.
The document discusses scouring, which is a process used to purify cotton and cotton-blended textiles by removing impurities like oils, waxes, and dirt. It describes two main types of scouring: alkaline scouring, which uses high concentrations of sodium hydroxide at high temperatures; and bio/enzymatic scouring, which uses enzymes like pectinase and lipase at lower temperatures. Alkaline scouring is faster and removes more impurities but is harsher on fibers, more costly, and produces more wastewater. Bio scouring is gentler on fibers, more environmentally friendly, and reduces costs over the full production process though it has
The document summarizes laboratory experiments conducted to measure local scour (erosion of sediment) around bridge piers arranged in different configurations. Equations were developed through statistical analysis to predict scour depth based on experimental data for single piers and pier groups. A new equation is proposed for predicting scour in pile groups. The effectiveness of slots in piers for minimizing scour is also examined.
Offshore Scour And Scour Protection Lecture29nov2010 TU DelftTimRaaijmakers
This document summarizes a presentation on scour and scour protection in the marine environment. It begins with an introduction that defines scour as erosion of sediment around structures due to increased flow. It describes differences between riverine and marine scour. It then covers mechanics of scour from waves, currents, and their combination. Applications sections discuss monitoring scour development around monopiles over time and validating predictions against field measurements. The document concludes after discussing mitigation measures and examples.
This document provides a market summary and outlook for the global shipping industry in 2015. It discusses trends in key shipping sectors such as containerships, oil and gas tankers, and bulk carriers. Specifically for containerships, it notes that liner companies increased cooperation through new alliances in 2014 and expects further consolidation. It also predicts continued growth of ultra-large containerships over 18,000 TEU as alliances seek economies of scale. Overall container trade is forecast to grow 6.5-7% in 2015 while the container ship fleet is expected to expand 7-7.5%, which could put pressure on freight rates if not balanced with other measures.
INGENUITY IN SOIL REINFORCEMENT METHODS AGAINST SCOUR FAILUREEdison Mugoya
GEOTECHNICAL ENGINEERING: INGENUITY IN SOIL
REINFORCEMENT METHODS AGAINST SCOUR FAILURE
is a study in geotechnical engineering regarding the scour failure at bridge abutments. its a methodology used to decrease it's effects and prolong the life cycle of bridge piers
Retrofitting the well foundation of a railway bridge subjected to scourSushil Dhungana
This document discusses retrofitting techniques for strengthening the well foundation of a railway bridge subjected to scour. It proposes two retrofitting methods: 1) Installing piles around the well foundation, but finds this would not fully transfer loads or relieve pressure. 2) Creating a shallow foundation around the well to partly transfer vertical loads, all moments, and protect against scour in the top 2.5-3m. Analysis shows bearing pressure is within capacity even for increased modern loading standards. The revised approach of a reinforced concrete ring foundation is suggested to strengthen the existing well foundation against failure due to bending stresses or scour.
A clear water scour around a circular bridge pier under steady flow for diffe...eSAT Journals
Abstract The loose non cohesive material through which a river flows is generally called sediment. Local scour at piers and abutments is the main reason for the collapse of bridges founded in alluvial sediments. Clear water scour refers to the situation where no sediment is supplied by the approaching flow in the zone of scour. Many investigators have studied various aspects of scour. However, the study on scour under steady condition for same discharge with same depth of flow for different pier diameters is limited. In present study laboratory experiment was conducted on different pier sizes of circular piers by keeping discharge constant under clear water scour condition. It is found that Non dimensional scour depth gradient is different up to opening ratio 0.8 having less slope and its slope is steep above 0.8 opening ratio. Keywords: -clear water scour; Froude’s number; sediment; equilibrium scour.
HYDRAULIC JUMP CHARACTERISTICS FOR DIFFERENT OPEN CHANNEL AND STILLING BASIN ...IAEME Publication
Hydraulic jump is considered as the best way for dissipating energy present in moving water downstream of hydraulic structures. This paper conducted laboratory experiments to investigate the hydraulic jump characteristics variations for different rectangular open channel layouts. In this paper, the used open channel layouts were five bed slopes of 0.0175, 0.0349, 0.0524, 0.0699, and 0.0875, and a sill with three different heights was placed along a model of the stilling basin at three different longitudinal distances. The characteristics of the hydraulic jump, which was formed downstream vertical gate, were measured for variable discharges.
This document summarizes a HECRAS sediment transport computational study for the removal of a low head dam on the Mahoning River. The study modeled 33.5 river miles encompassing two Ohio counties over a year-long period. Key findings were that the dam removal would result in over 230,000 additional tons of sediment transport downstream, accumulating above the next dam. Sediment movement increased during high flow conditions. Pre-removal sediment transport studies can help manage issues from increased sediment load.
There are many bridges in the US that were not designed to withstand scouring effects. Arc Surveying performs detailed surveys of bridges using technologies like multibeam sonar, laser scanning, and historical plans to create 3D models showing underwater structures, foundations, and riverbed changes over time. These comprehensive surveys allow authorities to assess scour vulnerability and monitor conditions. Arc has surveyed hundreds of bridges, with data made accessible online for emergency response.
Scour investigation around single and two piers sidebyside arrangementeSAT Journals
Abstract Laboratory experiments concerning scour development around single and two piers side by side arrangement have been conducted in order to provide a comparison of scour depths and patterns. The experiments are carried out under unidirectional currents of clear-water scour conditions. A variety of conditions including different flow depths, pier diameters and pier spacing are considered to have significant influence on the development of the potential scour hole. The research on local scour around single and two piers side by side arrangement are studied by using a 15.24 m long, 0.46 m wide and 0.4 m deep flume in the Hydraulics and Hydrology Laboratory, Universiti Teknologi Malaysia (UTM).Experimental results describing the scour-hole depths and patterns are discussed. The results show that the magnitude and extent of the scour depth depends directly on pier size, pier spacing and flow condition. Piers, which are larger in diameter, produced greater scour depth. It also shows that by increasing the pier spacing, the scour depth around two piers decreases and closes to values of single pier. The two piers act as an obstruction which disturbed the flow field and caused large turbulence levels to be generated. Thereby, a further increase in the scouring velocity is produced giving relatively higher scour depth values. The prime factors governing the local scouring process associated with piers are pier spacing, horseshoe vortex, reinforcing and sheltering. The results show that good agreement with previous study where the down flow causes of increased scour for a single pier case. Meanwhile, the horseshoe vortex appears to be the main cause of scour in the case of two piers side by side arrangement. Keywords: Scour depth, Flow pattern, Single pier, Side by side piers, Pier spacing, Horseshoe vortex
The document summarizes a student presentation on observing hydraulic jumps in underground drainage systems. The student's objectives were to observe the behavior of flows and resulting hydraulic jumps inside closed conduits, and to compare this to classical hydraulic jumps. The methodology involved setting up experiments in a glass flume and using pressure sensors to measure velocities and pressures as hydraulic jumps formed. Results showed classical hydraulic jumps could be generated and compared to theoretical equations.
Quick tutorial of how to conduct a bridge scour computation within HECRAS. Characteristics of stream stability fundamentals are also discussed. Abutment, pier, and contraction methodologies from HEC 18 are summarized. Tips to avoid common mistakes are provided. Helpful data sources to assist design are suggested.
Estimation of bridge pier scour for clear water & live bed scour conditionIAEME Publication
1) The document analyzes and compares several equations for estimating bridge pier scour depth under clear water and live bed conditions.
2) Statistical tests are used to validate the equations against experimental laboratory data from previous studies. The tests analyzed include Theil's Coefficient, Mean Absolute Error, and Root Mean Square Error.
3) The results show that for both clear water and live bed scour conditions, the Richardson equation generally provides the most reasonable estimates of scour depth compared to other common methods, according to the statistical test values.
The Ganga Action Plan was launched in 1986 to clean the Ganges River and restore it to its original condition. Phase I aimed to treat 882 million liters per day of wastewater generated in towns along the Ganges but failed to achieve this goal. Phase II expanded the project to include tributaries but still only treated a small portion of the total waste. Despite efforts, pollution levels in the river remain high due to untreated sewage and industrial waste entering the water. Better treatment technology is still needed to properly clean the river without negatively impacting biodiversity or human health.
This document presents a study on scour countermeasures for bridges. It includes an introduction and outlines chapters on the mechanism of scouring, factors affecting scouring, performance of various scour countermeasures, comparison of different countermeasure performances, threshold of rip rap failure, performance of sack gabions as countermeasures, and conclusions. Scouring refers to hydraulic erosion around bridge abutments and piers due to water flow, which can lead to geotechnical failures and is a major cause of bridge failures. The study evaluates different scour countermeasure techniques to protect bridges from scouring.
The document summarizes information about the Ganges River, including its religious significance in Hinduism, the cities along its banks, how it provides water to 40% of India's population, and how it has become heavily polluted in modern times due to human and industrial waste. It also discusses the objectives and phases of the Ganga Action Plan launched in 1986 to reduce pollution in the river, but which ultimately failed due to issues like inappropriate planning, lack of cooperation between levels of government, and not providing consistent electricity to run treatment facilities.
This study presents a laboratory experiments for evaluating the local scour depth
around S-shape solid non- submerged groynes using different number of these groynes
and also different distances between them as two countermeasures to reduce the
scour. The study was conducted in non- curved laboratory flume where uniform
cohesion-less sand of median size (d50) equal to (0.7 mm) was used as the bed
material. The physical hydraulic model of the groynes was made of polystyrene foam
with fixed dimensions to operate under steady subcritical flow and clear water
conditions. The studied parameters in this study were the number of groynes changed
three times (single, double, triple), the distances between them altered also three times
(1L, 1.5 L, 2L) and finally the hydraulic conditions (depth and velocity of the mean
flow) also changed four times for each parameter. A new empirical equation was
derived where its coefficient of determination indicates good agreement between the
predicted results and the observed ones experimentally.
The document provides details about the Mumbai Coastal Road Project which includes construction of India's first undersea tunnel. Some key points:
1) A 2.07 km long twin tunnel is being constructed as part of the project, with 1 km being under the sea, making it unique from other tunnels worldwide.
2) India's largest Tunnel Boring Machine (TBM) named 'Mavala' has been deployed to excavate the tunnel and broke excavation records.
3) The tunnels will be 11 meters in diameter and constructed using concrete segmental lining for structural support and stability.
4) Numerical analysis of stress redistribution during various construction stages and the long-term condition will be conducted
The document discusses the Eurasia Tunnel project in Istanbul, Turkey. The project involves constructing a 5.4 km twin-deck tunnel beneath the Bosphorus strait to alleviate pressure on the existing two bridges. A tunnel boring machine (TBM) was used to excavate 3.4 km of the tunnel through sediment and rock at depths over 100 m below sea level, the deepest TBM tunnel excavation at the time. Extensive geotechnical investigations were conducted to understand the soil and seismic conditions. Over 15,000 precast concrete tunnel segments were produced and installed using bolts to line the tunnel walls. The TBM excavation was completed in under 500 days, establishing new records for its power and operating pressure in
Assessing The Risk Of The Aswan High Dam BreachingFinni Rice
This document summarizes a study that assesses the risk of breaching of the Aswan High Dam in Egypt. The study involved reviewing literature on dam breaching, collecting site data and measurements from the Aswan High Dam, selecting a numerical model (HR-Breach Model) to simulate breaching scenarios, and analyzing the results to evaluate the risks and impacts of a potential dam failure. The study aims to help decision makers develop plans to address risks from a possible breach of the critically important Aswan High Dam.
A Review of Previous Work on an Approach to Design and Construction of Low He...IRJET Journal
This document reviews previous work on the design and construction of low height gravity dams. It discusses several past studies on related topics. Researchers have refined criteria for designing earth dams to resist piping and erosion. Construction of dams is needed on rivers carrying large rainwater flows. For the specific context of Lucknow, India, a dam needs to be built on the Gomti River without diverting the flowing water. Previous literature suggests constructing such a dam using geo bags, boulders, piling and earth over a period of 3 to 5 years. The stability and safety of earth dams against issues like overturning, sliding and piping has been explored in depth by other scholars.
The hydrogeological conditions for the construction of the subway in St. Petersburg
are complex. To avoid water flow in the tunnel, it is necessary to calculate the height
of water conducting fractures zone for massif. The article considers the geological
structure of the soil in St. Petersburg, the value of the boundary curvature for the massif
is calculated. The thickness of the sediments with disturbed water resistance was
determined, and the dangerous sections of the tunnel under construction in the Nevsko-
Vasileostrovskaya line are indicated.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
The document summarizes the design and construction of the foundations for the Rion Antirion Bridge in Greece. An innovative foundation concept was adopted using steel tubular piles driven into the seabed to reinforce the soil, with a gravel layer between the piles and the concrete caisson foundation. This concept provided seismic capacity and minimized differential settlement risks. Close cooperation between designers, contractors, and reviewers was essential to developing and implementing this challenging foundation solution.
This document presents a study on simulating vessel collisions with bridge piers to determine dynamic amplification factors. Finite element models of solid wall and hollow circular concrete piers with varying geometries are subjected to impact forces from barges and ships. Impact forces are estimated based on vessel size and speed. Dynamic and static responses are calculated to determine amplification factors for different pier designs and collision scenarios. The amplification factors provide an equivalent static force that can be used for more efficient pier design while still accounting for dynamic effects of vessel collisions. Graphs of the amplification factors aid in pier design for various inland waterway conditions.
A Review Study on Methods of Tunneling in Hard Rocksijsrd.com
This article presents a review on the different methodologies that are used for tunnels excavations in hard rocks in present era. Growing needs for modern transportation and utility networks have increased the demand for a more extensive and elaborate use of underground space or through high mountains / hills. As a result, more projects have to be completed in various ground conditions and one of which is more challenging is to carry out excavation work in hard rocks. Significant technological advances have rendered these projects possible, but have also given rise to new challenges as many of these projects have to be completed in difficult conditions, with very strict environmental constraints, particularly in urban areas where the potential impact of tunneling on existing structures is a major concern. This paper addresses the main aspects of tunneling and underground works performed in hard rocks. A summary is presented of the more recent advances and widely adopted techniques in these regards.
REVIEW PAPER ON “HYDRAULIC AND HYDROLOGICAL IMPACT ON BRIDGE”IRJET Journal
This document summarizes a review paper on the hydraulic and hydrological impacts on bridges. It discusses how hydrological and hydraulic studies are important for estimating flood levels and ensuring bridge design can withstand 100-year floods. The paper reviews different hydrological and hydraulic methods for calculating flood discharges at bridge locations. It also discusses fluid-structure interactions and how flood waters can impact bridge piers. Hydraulic data from case studies is presented, including catchment area, water levels, discharge rates and bridge proposals. The conclusions emphasize the need for river improvement works near bridges and continuous monitoring to avoid situations that could increase erosion.
Effect Of Water On Slope Stability And Investigation Of ΝΝw Drainage Techniqu...IJMER
This document summarizes a study on using drainage gravel piles to stabilize landslides along sections of the Egnatia Odos highway in Greece. Drainage gravel piles are vertical wells filled with permeable gravel that act as drains to lower the water table and pore water pressure within landslide-prone areas. The study investigates applying this technique to a landslide zone along the highway underlain by a buried river terrace with high permeability. It describes the geology and groundwater conditions contributing to landslides. Calculations are presented on the expected drawdown cone and impact radius of drainage gravel piles based on pumping test principles. The construction method is outlined. The study concludes drainage gravel piles can effectively drain landslide materials by channeling
Use of downstream facing aerofoil shaped bridge piers to reduce local scourIAEME Publication
This document discusses research on using downstream-facing aerofoil-shaped bridge piers to reduce local scour compared to traditional upstream-facing designs. It provides background on how scour occurs due to horseshoe vortices forming in front of piers. An experiment tested scour for circular, upstream-facing aerofoil, and downstream-facing aerofoil piers. Results showed the downstream-facing design reduced maximum scour depth by 59% versus the upstream aerofoil and 68% versus circular, and reduced the scour hole volume by 87% versus circular. Orienting the aerofoil shape to face downstream effectively weakened vortices causing scour.
1. The document discusses a study that uses finite element modeling to simulate subsurface drainage in roadways.
2. The study models unsaturated water flow through pavement layers using Richards equation and examines how layer properties like hydraulic conductivity affect drainage system performance.
3. The modeling reveals that subsurface drainage system performance depends not only on edge drain design but also on subgrade layer properties, with drainage decreasing as subgrade hydraulic conductivity increases.
This document summarizes research on sediment transport and coastal erosion along the Gaza coast. It discusses how construction of the Aswan Dam interrupted sediment supply from the Nile River in the 1960s, causing erosion. Methods used include analyzing historical satellite images from 1972-2010 to measure shoreline change and numerical modeling of mitigation structures. Modeling indicated relocating the fishing harbor offshore or using submerged breakwaters could help accretion by 28,000-4,000 m3/km annually, while detached breakwaters and groins caused erosion. The best alternative for restoration was found to be relocating the harbor offshore.
Bad drainage and its effects on road pavement conditions in nigeriaAlexander Decker
Poor drainage has significant negative effects on road pavement conditions in Nigeria. Inadequate drainage systems are common and allow water to accumulate on and penetrate into road surfaces. This leads to increased moisture content in road materials, reduced strength, mud pumping, cracking, stripping of asphalt, and damage from frost. The investigation found drainage deterioration and blockages contribute greatly to road deterioration in Nigeria. Maintaining proper drainage design, cross slopes, and drainage channel maintenance are important to effectively drain water and prevent moisture issues that compromise pavement integrity.
Experimental conceptualisation of the Flow Net system construction inside the...Dr.Costas Sachpazis
ABSTRACT
By means of a drainage and seepage tank, an experimental flow net system inside the body of a homogeneous earth embankment dam model, formed from Leighton Buzzard Silica sand, was developed and studied in this experimental research paper.
Water flow through dams is one of the basic problems for geotechnical engineers. Seepage analysis in an important factor to be considered in the proper design of many civil engineering structures. Seepage can occur in both through the structure itself as the case of earth dams and under foundations of an engineering structure. Successful seepage analysis is achieved on the proper and accurate construction of a flow net.
Amongst the various existing methods of seepage analysis, the “Finite Element Method” and the method of “Experimental Flow Nets” are the most widely used ones.
Construction of a flow net is mainly used for solving water flow problems through porous media where the geometry makes sometimes analytical solutions impractical. This method is usually used in soil mechanics, geotechnical or civil engineering as an initial check for problems of water flow under hydraulic structures like embankments or dams. As such, a grid obtained by drawing a series of equipotential lines and stream or flow lines is called a flow net. In this procedure the Laplace equation principles must be satisfied.
Hence, the construction of a flow net is an important tool in analysing two-dimensional irrotational flow problems and provides an approximate solution to the flow problem by following simple rules, as initially set out by Forchheimer, 1900, and later refined by Casagrande,1937. It can also be very useful tool even for problems with complex geometries, as proven in this experimental research paper.
The objectives of this experimental research paper are:
• To determine the position and shape of the flow line representing the uppermost free water surface inside the body of a dam by using a drainage and seepage tank,
• To conceptualise the flow lines system and to demonstrate that each flow line starts perpendicular to the upstream slope of the dam and that that slope is a boundary equipotential line,
• To construct an experimental flow net and subsequently to verify and analyse it by the FEA method,
• To calculate the rate of seepage through the dam body, and
• To summarise the calculations and experimental findings in a concise and readable format.
In order to achieve these objectives, an experimental flow net system inside the body of a homogeneous earth embankment dam model was formulated by using a drainage and seepage tank.
From the constructed flow net in the present experimental research paper, an attempt has been made to analyze, determine and present the following parameters:
The pressure drop from one side of the embankment to the other,
The seepage flow rate in each flow “channel”,
The total seepage flow rate, and
The pore pressure ratio, ru, for the embankment.
River training involves constructing structures along or across rivers to improve the river and protect its banks. It is necessary due to rivers frequently changing course in alluvial plains, which can erode banks and damage nearby land and property. River training structures are classified as transversal, perpendicular to flow to reduce velocity, or longitudinal, parallel to flow along banks. This document discusses various river training methods like guide banks, embankments, groynes and pitching, which are used to safely direct flood flows, prevent erosion and channel changes, and aid navigation. It provides design criteria for different structures and their components.
This document summarizes the design and construction of the Rion-Antirion Bridge in Greece. Some key points:
- The bridge spans 2,252 meters over the Gulf of Corinth and connects the Peloponnese to mainland Greece. It was completed in 2004.
- The environment presented challenges like deep water, weak soil, seismic activity, and strong winds. Foundations consisted of large caissons on reinforced soil with steel inclusions.
- The cable-stayed bridge has a continuous and fully suspended steel-concrete deck. It is equipped with seismic dissipation systems including hydraulic dampers to absorb energy from earthquakes.
- Innovative designs like the soil reinforcement and seismic protection
The document provides details on the design of the third phase of the Thannermukkom salt water barrier bridge. It includes the design of the following bridge components:
1) Deck slab using Pigeaud's curves to calculate bending moments from dead and live loads.
2) Cantilever slab, longitudinal girders, cross girders, bearings, pedestals, operating platform, pier, pier cap, pile, pile cap and apron designed based on codes and previous project details.
3) Pier design carried out using STAAD Pro software. Reinforced concrete grade M30 and steel grade Fe415 are used.
The preliminary dimensions and design loads as per IRC codes are
Similar to A study of local scour at bridge pier (20)
Electric vehicle and photovoltaic advanced roles in enhancing the financial p...IJECEIAES
Climate change's impact on the planet forced the United Nations and governments to promote green energies and electric transportation. The deployments of photovoltaic (PV) and electric vehicle (EV) systems gained stronger momentum due to their numerous advantages over fossil fuel types. The advantages go beyond sustainability to reach financial support and stability. The work in this paper introduces the hybrid system between PV and EV to support industrial and commercial plants. This paper covers the theoretical framework of the proposed hybrid system including the required equation to complete the cost analysis when PV and EV are present. In addition, the proposed design diagram which sets the priorities and requirements of the system is presented. The proposed approach allows setup to advance their power stability, especially during power outages. The presented information supports researchers and plant owners to complete the necessary analysis while promoting the deployment of clean energy. The result of a case study that represents a dairy milk farmer supports the theoretical works and highlights its advanced benefits to existing plants. The short return on investment of the proposed approach supports the paper's novelty approach for the sustainable electrical system. In addition, the proposed system allows for an isolated power setup without the need for a transmission line which enhances the safety of the electrical network
A SYSTEMATIC RISK ASSESSMENT APPROACH FOR SECURING THE SMART IRRIGATION SYSTEMSIJNSA Journal
The smart irrigation system represents an innovative approach to optimize water usage in agricultural and landscaping practices. The integration of cutting-edge technologies, including sensors, actuators, and data analysis, empowers this system to provide accurate monitoring and control of irrigation processes by leveraging real-time environmental conditions. The main objective of a smart irrigation system is to optimize water efficiency, minimize expenses, and foster the adoption of sustainable water management methods. This paper conducts a systematic risk assessment by exploring the key components/assets and their functionalities in the smart irrigation system. The crucial role of sensors in gathering data on soil moisture, weather patterns, and plant well-being is emphasized in this system. These sensors enable intelligent decision-making in irrigation scheduling and water distribution, leading to enhanced water efficiency and sustainable water management practices. Actuators enable automated control of irrigation devices, ensuring precise and targeted water delivery to plants. Additionally, the paper addresses the potential threat and vulnerabilities associated with smart irrigation systems. It discusses limitations of the system, such as power constraints and computational capabilities, and calculates the potential security risks. The paper suggests possible risk treatment methods for effective secure system operation. In conclusion, the paper emphasizes the significant benefits of implementing smart irrigation systems, including improved water conservation, increased crop yield, and reduced environmental impact. Additionally, based on the security analysis conducted, the paper recommends the implementation of countermeasures and security approaches to address vulnerabilities and ensure the integrity and reliability of the system. By incorporating these measures, smart irrigation technology can revolutionize water management practices in agriculture, promoting sustainability, resource efficiency, and safeguarding against potential security threats.
Introduction- e - waste – definition - sources of e-waste– hazardous substances in e-waste - effects of e-waste on environment and human health- need for e-waste management– e-waste handling rules - waste minimization techniques for managing e-waste – recycling of e-waste - disposal treatment methods of e- waste – mechanism of extraction of precious metal from leaching solution-global Scenario of E-waste – E-waste in India- case studies.
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.
Presentation of IEEE Slovenia CIS (Computational Intelligence Society) Chapte...University of Maribor
Slides from talk presenting:
Aleš Zamuda: Presentation of IEEE Slovenia CIS (Computational Intelligence Society) Chapter and Networking.
Presentation at IcETRAN 2024 session:
"Inter-Society Networking Panel GRSS/MTT-S/CIS
Panel Session: Promoting Connection and Cooperation"
IEEE Slovenia GRSS
IEEE Serbia and Montenegro MTT-S
IEEE Slovenia CIS
11TH INTERNATIONAL CONFERENCE ON ELECTRICAL, ELECTRONIC AND COMPUTING ENGINEERING
3-6 June 2024, Niš, Serbia
Comparative analysis between traditional aquaponics and reconstructed aquapon...bijceesjournal
The aquaponic system of planting is a method that does not require soil usage. It is a method that only needs water, fish, lava rocks (a substitute for soil), and plants. Aquaponic systems are sustainable and environmentally friendly. Its use not only helps to plant in small spaces but also helps reduce artificial chemical use and minimizes excess water use, as aquaponics consumes 90% less water than soil-based gardening. The study applied a descriptive and experimental design to assess and compare conventional and reconstructed aquaponic methods for reproducing tomatoes. The researchers created an observation checklist to determine the significant factors of the study. The study aims to determine the significant difference between traditional aquaponics and reconstructed aquaponics systems propagating tomatoes in terms of height, weight, girth, and number of fruits. The reconstructed aquaponics system’s higher growth yield results in a much more nourished crop than the traditional aquaponics system. It is superior in its number of fruits, height, weight, and girth measurement. Moreover, the reconstructed aquaponics system is proven to eliminate all the hindrances present in the traditional aquaponics system, which are overcrowding of fish, algae growth, pest problems, contaminated water, and dead fish.
Harnessing WebAssembly for Real-time Stateless Streaming PipelinesChristina Lin
Traditionally, dealing with real-time data pipelines has involved significant overhead, even for straightforward tasks like data transformation or masking. However, in this talk, we’ll venture into the dynamic realm of WebAssembly (WASM) and discover how it can revolutionize the creation of stateless streaming pipelines within a Kafka (Redpanda) broker. These pipelines are adept at managing low-latency, high-data-volume scenarios.
International Conference on NLP, Artificial Intelligence, Machine Learning an...gerogepatton
International Conference on NLP, Artificial Intelligence, Machine Learning and Applications (NLAIM 2024) offers a premier global platform for exchanging insights and findings in the theory, methodology, and applications of NLP, Artificial Intelligence, Machine Learning, and their applications. The conference seeks substantial contributions across all key domains of NLP, Artificial Intelligence, Machine Learning, and their practical applications, aiming to foster both theoretical advancements and real-world implementations. With a focus on facilitating collaboration between researchers and practitioners from academia and industry, the conference serves as a nexus for sharing the latest developments in the field.
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.
ACEP Magazine edition 4th launched on 05.06.2024Rahul
This document provides information about the third edition of the magazine "Sthapatya" published by the Association of Civil Engineers (Practicing) Aurangabad. It includes messages from current and past presidents of ACEP, memories and photos from past ACEP events, information on life time achievement awards given by ACEP, and a technical article on concrete maintenance, repairs and strengthening. The document highlights activities of ACEP and provides a technical educational article for members.
1. Seventh International Water Technology Conference IWTC 2003 Egypt
A STUDY OF LOCAL SCOUR AT BRIDGE PIERS
OF EL-MINIA
Dr. Gamal A. Sallam1
and Dr. Medhat Aziz2
ABSTRACT
Bridges are critical structures that require a substantial investment to
construct and serve an important role in economic development. For a
developing country such as Egypt, there is need to protect these assets by
continuous monitoring, maintenance, proposing any required repair works
and execute them with a very high quality control. El-Minia Bridge was
constructed in 1987. It consists of 15 vents each of 40.00 m wide, except
the navigation vent, which is 62.00 m wide. Recently, there have been
some difficulties regarding navigation underneath the bridge. Since some
submerged islands are formed near the navigational vent, some deposition
near the navigational vent of the bridge has raised the bed level. This has
resulted in an insufficient depth of water for navigation through the
navigational vent. In addition, river bed has changed around bridge piers.
Nile Research Institute (NRI) has conducted the analysis for this problem
to avoid any damages that could occur to the bridge. Nile Research Institute
research team were sent for collecting the field data for the site of El-Minia
Bridge Km. 205.050 upstream of El-Roda site along the Nile River, in
which pier size, sediment size and mean approach flow velocities are
recorded. A mathematical model was used to study the measured scour
hole values and to predict to predict the future maximum expected scour
hole. That was conducted to evaluate the causes and consequences of scour
holes on the bridge piers of El-Minia. In addition, some methods and tools
for minimize the effect of scour holes on the bridge piers were discussed.
KEYWORDS:
Nile River Bridges, Local scour, Bridge local scour.
Researcher, Nile Research Institute, Egypt
Assoc. Prof., Nile Research Institute, Egypt
2. Seventh International Water Technology Conference IWTC 2003 Egypt
1. INTRODUCTION
El-Minia bridge constructed in 1987 to join El-Minia City with the
west main highway (2) (Egypt - Aswan) and with the main new highway
(Cairo/ Bani Suif/ El-Minia) East of the River Nile which was constructed
lately through the main Governorate plan to support the network roads and
to decrease the traffic density on the Upper Egypt highway. The new El-
Minia Bridge will create a new civilization on the East of River Nile, in
addition to gain the best use for stone quarries in this area. The total length
of El-Minia Bridge is about 1803 m, it consists of 15 vents, width of each is
40 m. While the navigational vents, the biggest is about 62 m and on each
side 2 vents with a width of about 50 m and the maximum navigational
height is 13 m from the highest water level of River Nile. The total road
width on the bridge is 21 m, the bridge foundations are penetrated piles
with a length of about 20 m, all these piles are supported on sand or stone
soils.
Yet every year more additions are made to the list of bridges that
have failed because of scour of the stream bed around the piers and
abutments. Considering the overall complexity of field conditions, it is not
surprising that there is no generally accepted principles for the prediction of
scour around bridge piers and abutments have evolved from field
experience alone, (Emmett M. Laursen and Arthur Toch, 1956). The
alignment, cross section, discharge, and slope of a stream must all be
correlated with the scour phenomenon, and this in turn must be correlated
with the characteristics of the bed material ranging from clays and fine silts
to gravels and boulders. Finally, the effect of the shape of the obstruction
itself - the pier or abutment - must be assessed.
The equilibrium of any river under natural flows is affected by any
interference. Some examples of the interfering structures are bridges,
groins and hydraulic structures. Study the effect of any of these structures
before and after construction is an important factor to avoid any unexpected
results.
One of the Nile Research Institute tasks is to monitor, study, and
analyze these effects and to propose the suitable measures to be taken to
protect these structures and avoid major changes to the river, (Ahmed
Fahmy, 2002). During this research local scour caused by bridges is
3. Seventh International Water Technology Conference IWTC 2003 Egypt
analyzed, a case study, El-Minia Bridge, is considered for this analysis.
Figure (1) shows El-Minia Bridge along the River Nile.
Figure (1) El-Minia bridge location along the River Nile
2. SCOUR PHENOMENON
Scour is the removal of bed and bank material as a result of the
erosive action of flowing water. The three components of total scour are
general scour, contraction scour, and local scour.
The contraction scour is the scour that results from the acceleration
of the flow due to a contraction, such as a bridge. This type of scour also
occurs in areas where revetments are placed such that they reduce the
overall width of the stream segment. Contraction scour is generally limited
to the length of the contraction, and perhaps a short distance up and
downstream, whereas general scour tends to occur over longer reaches.
The local scour is the scour that occurs at a pier, abutment, erosion
control device, or other structure obstructing the flow. These obstructions
cause flow acceleration and create vortexes that remove the surrounding
sediments. Generally, depths of local scour are much larger than general or
contraction scour depths, often by a factor of ten. Local scour can affect the
4. Seventh International Water Technology Conference IWTC 2003 Egypt
stability of structures such as riprap revetments and lead to failures if
measures are not taken to address the scour.
Factors that affect local scour include:
1. width of the obstruction
2. length of the obstruction
3. depth of flow
4. velocity of the approach flow
5. size of the bed material
6. angle of the approach flow (angle of attack)
7. shape of the obstruction
8. bed configuration
9. debris
3. FIELD INVESTIGATIONS
A field trip has been carried out to El-Minia Bridge; the bridge is
located in El-Minia Governorate, kilometer 242.050 along the River Nile
south of Cairo. This field trip was conducted to observe, measure, and
monitor the different factors affecting bridge local scour. This field trip has
included the water levels at the site, bridge pier dimensions and geometry.
Figure (2) shows one of the El-Minia Bridge piers as an example. A
hydrographic survey of the bed nearby and around bridge piers was
performed along the riverbed covering 1.00 Km (about 500 meter upstream
and 500 meter downstream the bridge), and 21 surveyed cross sections.
Velocity measurements were taken at five locations, two cross-sections
upstream the bridge, two cross-sections downstream bridge and at the
centerline of bridge. Samples of bed material were taken at the same cross-
sections. Table (1) shows surface bed grain size analysis at the bridge site.
It is noted from the grain size distribution that most of the bed samples are
medium sand with D50 ranging from 0.25 to 0.50 mm (medium sand is
ranging from 0.2 to 0.60 mm). Downstream cross sections have some
coarse sand ratio. It has to be noticed also that this is typical configuration
for the Nile River bed, and the existence of fine sand indicates the
possibility of further scour. Figure (3) shows the cross section changes at
the bridge for years 1982 and 2002. It is observed the major cross section
changes due to bridge existence. It can be noticed that a maximum local
scour depth of about 4.60 m has occurred during the period 1982 to 2001.
5. Seventh International Water Technology Conference IWTC 2003 Egypt
Figure (2) One of the El-Minia bridge piers
Table (1) Surface bed grain size analysis at the bridge site
X-S
KM.
from
Aswan
High
Dam
LOCATION D 50
(mm)
D mean
(mm)
SOIL
TYPE
UPSTREAM
THE BRIDGE
684.910 Point 1
East
0.40 0.44 Medium sand
Point 2 0.25 0.28 Medium sand
Point 3 0.29 0.31 Medium sand
Point 4 0.42 0.47 Medium sand
Point 5
West
0.40 0.43 Medium sand
CENTER LINE
OF BRIDGE
684.940 Point 1 0.27 0.27 Medium sand
Point 2 0.32 0.32 Medium sand
DOWNSTREAM
THE BRIDGE
684.960 Point 1
East
0.50 0.55 Medium to
coarse sand
Point 2 0.42 0.47 Medium sand
Point 3 0.24 0.27 Medium to
fine sand
Point 4 0.42 0.50 Medium to
coarse sand
Point 5 0.25 0.24 Medium to
fine sand
6. Seventh International Water Technology Conference IWTC 2003 Egypt
A study of local scour at bridge piers of El-Minia bridge
20
22
24
26
28
30
32
34
36
38
0 100 200 300 400 500 600
Distance (m)
Bedlevel(m)
1982 2002
Figure (3) Cross section changes at the bridge (1982 and 2002)
4. COMPUTING SCOUR
Because of complexity of evaluating flow pattern around piers and
shear forces generated by flow pattern, most of the estimates of scour depth
have been obtained by experimental work. An example of these estimates
is the Colorado State University (CSU) equation for predicting maximum
pier scour depths, the equation is (ASCE, 1975):
Ys/Y1 = 2.0 K1 K2 K3 K4 (A/Y1)0.65
Fr1
0.43
for round nose piers aligned with the flow.
where:
Ys = Scour depth, m
Y1 = Flow depth directly upstream of the pier, m
K1, K2, K3, and K4 = Correction factors for pier nose, angle of attack,
bed condition, and armoring by bed material size
respectively.
A = Pier width, m
7. Seventh International Water Technology Conference IWTC 2003 Egypt
L = Length of pier, m
Fr1 = Froude Number directly upstream of the pier.
Ys ≤ 2.4 times the pier width (A) for Fr ≤ 0.8
Ys ≤ 3.0 times the pier width (A) for Fr > 0.8
5. COMPUTER MODEL
A Computer Model: The computer model HEC-RAS Model was
used during this analysis to evaluate local scour around El-Minia Bridge
piers. This model is developed by the US Army Corps of Engineers (US
Army Corps of Engineers, 2001). It is a one-dimensional model able to
simulate steady, unsteady and sediment transport for movable boundary
conditions. It has a special module to compute bridge piers and abutment
local scour. To be able to simulate the actual flow conditions, the whole
reach (Reach 4 - from downstream Assiut Barrage to upstream Delta
Barrage) has to be modeled and analyzed.
Reach 4: It extends downstream Assiut Barrage to upstream Delta
Barrage with a total length of about 410.00 km. It is the longest reach all
over the Nile River reaches. The surveyed cross sections for this reach in
both years 1982, 1997 and 2002 were used for this analysis. Figure (4)
shows the location of Reach 4 along the River Nile, and Table (2) shows
the cross section locations along the reach used during this study.
8. Seventh International Water Technology Conference IWTC 2003 Egypt
Figure (4) Location of reach 4 along the River Nile
Model Calibration Process: The actual water level readings for
gauging stations along the fourth reach were used for the calibration
analysis. Two actual flow conditions were considered for the calibration
analysis; 170 and 350 million cubic meters per day. Figure (6) shows the
calibration process for the flow of 170 m.m3
/day and Figure (7) shows the
calibration process for the flow of 350 m.m3
/day. From these two figures,
we can conclude that there is a close agreement between measured and
predicted water levels. This indicates that the selected roughness values are
suitable for the simulation process.
Reach 4
9. Seventh International Water Technology Conference IWTC 2003 Egypt
Table (2) Cross Section Locations
Number Cross
Section
Km from
Aswan
Number Cross
Section
Km from
Aswan
1 93 555 21 135 767
2 94 556.5 22 137 778
3 96 572.85 23 139 787
4 98 582 24 140 795
5 100 591 25 141 798
6 102 602 26 143 806.4
7 104 612 27 145 830.8
8 106 623.5 28 146 835
9 108 633.5 29 147 843.2
10 110 645 30 149 851.3
11 112 654 31 151 862.4
12 114 664 32 153 873.3
13 116 671 33 154 879
14 118 681 34 155 887.3
15 120 691 35 157 901.1
16 122 701 36 159 912.7
17 125 719.5 37 161 915.2
18 127 727 38 162 927
19 129 738 39 163 947.6
20 131 747
6. INPUT DATA
The data that are provided to the program is as follows:
1. Bed material grain size distribution, Table (1).
2. Reach 4 cross sections 5 Km a part, Table (2).
3. Water level for reach 4 gauging stations.
4. Bridge geometry pier dimensions, Figure (2) shows one of these
piers, where the pier width is 1.50 meter, and the pier length is
10.00 meter.
7. LOCAL SCOUR SIMULATION
Figure (5) shows the model output for the simulated flow conditions.
The simulated flow, considered during this analysis, is 180 m.m3
/day. This
flow is considered to simulate flow conditions causing local scour around
the bridge piers. This flow is almost the largest flow discharge passed along
this reach during the past period (1982-2002) and it is close to the
10. Seventh International Water Technology Conference IWTC 2003 Egypt
calibration discharges. The computed water levels along the reach are
shown in this figure.
0 100000 200000 300000 400000
0
10
20
30
40
50
60
reach 4 brdg Plan: Plan 06
Main Channel Distance (ft)
Elevation(ft)
Legend
EG PF 2
WS PF 2
Crit PF 2
Ground
4
Figure (5) The model output for the computed water level
11. Seventh International Water Technology Conference IWTC 2003 Egypt
Figure (6) The calibration results for 170 m.m3
/day
Figure (7) The calibration results for 350 m.m3
/day
Model Calibration (350 m.m3/day)
0
10
20
30
40
50
60
500 550 600 650 700 750 800 850 900 950 1000
Km (from Aswan)
Level(m)
Predicted Measured
Model Calibration (170 m.m3/day)
0
5
10
15
20
25
30
35
40
45
50
500 550 600 650 700 750 800 850 900 950 1000
Km (from Aswan)
Level(m)
Predicted Measured
12. Seventh International Water Technology Conference IWTC 2003 Egypt
9. MODEL RESULTS
The model results represent the local scour occurred due to passing a
discharge of 180 m.m3
/day along El-Minia Bridge. Bed material gradations
were included for this analysis to compute the local scour. The CSU
equation is used by the model for local scour computations. The K terms
are taken as follows:
K1 correction factor for pier nose is taken as 1.00
K2 angle of attack of flow 90.0
K3 correction factor for bed conditions 1.1
(clear water scour)
K4 armoring effect coefficient 0.7
The computed scour represents both the contraction and the piers
scour occurred for this flow condition. The abutment local scour is not
applicable for this case because there were no interfering abutments to the
flow. Table (3) shows the results of the local scour for the bridge piers. A
maximum value of 4.9 meters was computed for pier scour. It has to be
mentioned that the value obtained from comparing the cross section (1982-
2002) is about 4.60 m of local scour and degradation for the bridge cross
section. Figure (3), shows cross section change at the bridge (1982-2002).
Also, Table (3) shows the computed local scour for 180 m.m3
/day and a
maximum flow of 350 m.m3
/day. The differences between the measured
and the computed local scour depths could be attributed to the variation of
bed grain size distribution and model simplification but the model gives a
good indication for the local scour values. However, the maximum
computed expected local scour is 5.60 m, which should be taken into
consideration during future programs.
Table (3) Computed local scour for a flow of 180 m.m3
/day
and 350 m.m3
/day
Piers Local scour of
180 m. m3
/ day
Local scour of
350 m. m3
/ day
All 4.9 meter 5.6 meter
13. Seventh International Water Technology Conference IWTC 2003 Egypt
10. CONCLUSION AND RECOMMENDATIONS
- Local scour monitoring is very important to avoid major damages
that may occur.
- The monitoring of El-Minia bridge local scour shows a local scour
depth of about 4.60 m since its construction up till now.
- The mathematical simulation of the bridge local scour shows a local
scour of a depth 4.90 m. that means the difference between the
measured scour and calculated scour about 6.5 %.
- The HEC-RAS model is a good tool for predicting local scour for
bridge piers. Hence, it could be used to determine the type of bridge
pier foundations before constructing.
- The expected local scour of passing a discharge of 350 m.m3
/day is
about 5.60 m.
- Since the local scour was found 4.60 m during the last 10 years and
the bridge pier foundations can tolerate this scour. It is recommended
to continue local scour monitoring every 5 years minimum.
REFERENCES
Ahmed Fahmy, “A study of local scour around El-Minia Bridge”, Report
No 341, Nile Research Institute, National Water Research Center, Egypt
(2002).
ASCE Manuals and Reports on Engineering Practice, “Sedimentation
Engineering”, ASCE, No.54, 1975.
Bruce W. Melville, “Live-Bed Sour at Bridge Piers”, J., Hyd. Div., ASCE,
Vol. 110, No. 9, (1984).
Emmett M. Laursen and Arthur Toch, “Scour around Bridge Piers and
Abutments”, Iowa Institute of Hydraulic Research, State University of
Iowa, (1956).
14. Seventh International Water Technology Conference IWTC 2003 Egypt
US Army Corps of Engineers, “HEC-RAS River Analysis System
Computer Model”, The Hydrologic Center, Davis, California, 2001.