The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Design of water tank (RCC design) By Working Stress Method as per Indian Standards.
Useful for Practicing Civil Engineers & Students of B.Tech & B.E in civil
Seismic behavior of rc elevated water tankunder different types of staging pa...CADmantra Technologies
CADmantra Technologies Pvt. Ltd. is one of the best Cad training company in northern zone in India . which are provided many types of courses in cad field i.e AUTOCAD,SOLIDWORK,CATIA,CRE-O,Uniraphics-NX, CNC, REVIT, STAAD.Pro. And many courses
Contact: www.cadmantra.com
www.cadmantra.blogspot.com
www.cadmantra.wix.com
Design of water tank (RCC design) By Working Stress Method as per Indian Standards.
Useful for Practicing Civil Engineers & Students of B.Tech & B.E in civil
Seismic behavior of rc elevated water tankunder different types of staging pa...CADmantra Technologies
CADmantra Technologies Pvt. Ltd. is one of the best Cad training company in northern zone in India . which are provided many types of courses in cad field i.e AUTOCAD,SOLIDWORK,CATIA,CRE-O,Uniraphics-NX, CNC, REVIT, STAAD.Pro. And many courses
Contact: www.cadmantra.com
www.cadmantra.blogspot.com
www.cadmantra.wix.com
This presentation provides you the conceptual knowledge as per DBATU, Lonere Last Year BTech Civil subject, Infrastructure Engg. Module-V Tunnel Engineering
Shape and Size of Tunnel Shafts, Pilot Tunnels, Tunneling in Hard Rock, Tunneling in Soft Materials, Drilling-Patterns, Blasting, Timbering, Mucking, Tunnel Lining, Advances In Tunneling Methods, Safety Measures, Ventilation, Lighting and Drainage of Tunnels
etc.
In this you will find some of the basic thing regarding the elevated water tank and this is our one of the team project work in college. Hope you will enjoy it....
Time History Analysis of Circular and Rectangular Elevated Water Storage Tank...Dr. Amarjeet Singh
In the world, there are large number of storage tanks which are used as water and oil storage facilities. Elevated water tank is one of the most important structures in earthquake event. As known from very upsetting experiences, elevated water tanks were heavily damaged or collapsed during earthquake Hence different configurations of liquid storage tanks have been constructed. Water tanks are play an important role in municipal water supply and firefighting systems. Due to post earthquake useful desires, seismic safety of water tanks is most important. In the current study time history analysis of rectangular and circular elevated water storage tank were analyzed using SAP 2000 software. In this study the concrete baffle wall was used to reduce sloshing effect of the water tank. The tank responses such as maximum nodal displacement, base shear and result were compared for empty and full tank water fill condition. From IS 11682:1985provision when seismic loading is considered only two cases may be taken one is tank empty condition and other is tank full condition. Finally, study discloses the importance of suitable supporting baffle wall to remain withstand against heavy damages of circular and rectangular elevated water tanks during earthquake. As per IITK-GSDMA guidelines for seismic design of liquid storage tanks, hydrodynamic pressure for impulsive and convective mode was calculated.
Necessity/advantage of a tunnel, Classification of Tunnels,
Size and shape of a tunnel, Alignment of a Tunnel, Portals and Shafts,
Methods of Tunneling in Hard Rock and Soft ground, Mucking, Lighting
and Ventilation in tunnel, Dust control, Drainage of tunnels, Safety in
tunnel construction.
Comparative Study on the Design of Square,Rectangular and Circular Concrete W...IJERA Editor
Reinforced concrete overhead water tanks are used to store and supply safe drinking water. Design and cost estimation of overhead water tanks is a time consuming task, which requires a great deal of expertise. This study therefore examines the efficiency of Rectangular and Circular tanks. Tanks of 30m3, 90m3, 140m3 and 170m3 capacities were used in order to draw reasonable inferences on tank‟s shape design effectiveness, relative cost implications of tank types and structural capacities. Limit state design criteria were used for basic tank‟s construction materials- steel reinforcement, concrete and formwork were taken-off from the prepared structural drawings. Results of the material take-offs showed that, for each of the shapes, the amount of each structural materials increase as the tank capacity increases. Also Circular-shaped tank consumed lesser individual material as compared to Rectangular ones. Hence, this will give Circular-shaped tanks a more favoured selection over the rectangular shaped tanks.
Seismic analysis of water tank considering effect on time periodeSAT Journals
Abstract While comparing both IS 1893-1984 and IS 1893(part II), first section we consider effect of Seismic responses-base shear, base moment, direction of seismic force, effect of vertical ground acceleration, maximum hydrodynamic pressure, sloshing wave height and additional parameters which calculated using response spectra with change in staging height and performing a few simple calculations and graphs. Here we observe the effect on time period with reference to the staging height in same sample calculations and graph obtained for different quantity. And also collecting the actual site dimension’s (parameters) situated in Nagpur, for evaluation effect of staging height on earthquake forces and effect of soil type conditions on earthquake forces with constant zone, analyzing the tank in SAP2000 for stiffness at different staging height. And analysis has been done by both IS codes. This analysis shows the difference between the all the parameters. Keywords: IS 1893-1984, IS 1893(part II), SAP2000
A bridge is the key element in a transportation system; it controls both the volume and weight of the traffic. Balance must be achieved between handling future traffic volume and loads and the cost of heavier and wider bridge structure. Economic Analysis and comparisons against competing alternatives is required as Bridges are the most expensive part of a road transportation network. Monetized & Non-Monetized Benefits that will accrue like time savings to road users, benefits to business activities (and to the economy in general) and salvage value benefits like Right-of-Way and substructure use need to be assessed as well.
Seismic behavior of elevated water tankeSAT Journals
Abstract Hydrodynamic analysis of elevated water tank is a complex procedure involving fluid structure interaction. The elevated tank supports large water mass at the top of slender staging. In case of elevated tank the resistance against lateral forces exerted by earthquake is largely dependent of supporting system. Staging is considered to be a critical element as far as lateral resistance is concern. Satisfactory performance of staging during strong ground shaking is crucial. In this paper seismic behavior of elevated water tank in view point of their supporting system is evaluated using finite element software ETABS. The main objective is to evaluate a performance of different staging system for elevated water tank using finite element software ETABS. The spring mass model consisting of impulsive and convective masses as per IS 1893:2002 Part 2 has been used for the analysis. The parametric study is performed on mathematical model with different staging system to evaluate their performance with regard to lateral stiffness, displacement, time period, seismic base shear, overturning moment, flexure etc. Keywords: Hydrodynamic analysis, Staging Performance, spring mass model, ETABS
Concrete Gravity Dam Components
A gallery is a small passage in a dam for providing an access to the interior of the dam.
The gallery is usually rectangular in shape with its top and bottom either flat or semi circular.
For a gallery with its top and bottom flat, it is necessary that all the corners should be rounded. The width of gallery generally varies from 1.5 to 1.8 m. The height of the gallery in between 2.2 to 2.4 m, so that a person can easily walk inside it.
To provide drainage of the dam section.
2. To provide space for equipment required for drilling holes and grouting the hole to form a grout curtain in the foundation.
3. To provide space for header and return pipes for post cooling of concrete.
4. A gallery provide an access to the interior of the dam for inspection ard maintenance.
5. A Gallery also provides space for installing various instruments in the dam to study its structural behaviour.
6. A gallery can provide space for the mechanical and electrical equipment required for the operation of gates for spillways and outlets.
A shaft is a vertical opening provided in a dam. Shafts are required for locating headers of the post cooling system and for locating measuring devices.
Shafts are also required for the movement of elevators and the hoisting equipment. Sometimes shafts are constructed inclined to connect two galleries or the same gallery at two different elevations by a staircase or a lift arrangement.
A plumb line shaft is constructed at the maximum section of the dam to make observations of the deflection of the dam under loads.
A plumb bob is suspended by a wire fixed at the top of the shaft. As the dam deflects relative to the base, the plumb bob also moves by the same amount.
A stilling well shaft is a special shaft used to record fluctuations of the water level in the reservoir. The shaft is connected to the reservoir at a point below the minimum reservoir level.
There is a floating mechanism in the stilling well shaft which records fluctuations in the water level.
The spillway in a gravity dam is called overflow section. Spillway is provided to dispose of surplus water from the reservoir to the downstream.
Spillways are provided for all dams as a safety measure against overtopping and the consequent damages, and failure. spillway may be located either in the middle of the dam or at the end of the dam near abutment.
It must have adequate discharge capacity.
It must be hydraulically and structurally safe.
The surface of the spillway must be erosion resistant.
It should be provided with some device for the dissipation of excess energy
The portion of the gravity dam other than the spillway is a non-overflow section, a road is located on the non-overflow section of the dam.
At the one end of a gravity dam a power house is located. Water from the reservoir passes tnrough penstock and rotates the turbine provided at power elevations to produce electricity.
Water flowing over a spillway has a ver
The presentation summarizes the project work done on "Seismic Analysis of Elevated Water Tank". Elevated water tanks are important structures that serve the function of supplying municipal water to the civil community. The stability of such structure is highly uncertain in the eve of earthquake. This project analyses the performance of such a structure in the eve of earthquake.
The project is done as a course requirement for undergraduate degree in May 2013. The degree in pursuit was "Bachelor of Technology in Civil Engineering" in National Institute of Technology in Tiruchirappalli (INDIA). The authors were in final year of the study during the making of the project.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
This presentation provides you the conceptual knowledge as per DBATU, Lonere Last Year BTech Civil subject, Infrastructure Engg. Module-V Tunnel Engineering
Shape and Size of Tunnel Shafts, Pilot Tunnels, Tunneling in Hard Rock, Tunneling in Soft Materials, Drilling-Patterns, Blasting, Timbering, Mucking, Tunnel Lining, Advances In Tunneling Methods, Safety Measures, Ventilation, Lighting and Drainage of Tunnels
etc.
In this you will find some of the basic thing regarding the elevated water tank and this is our one of the team project work in college. Hope you will enjoy it....
Time History Analysis of Circular and Rectangular Elevated Water Storage Tank...Dr. Amarjeet Singh
In the world, there are large number of storage tanks which are used as water and oil storage facilities. Elevated water tank is one of the most important structures in earthquake event. As known from very upsetting experiences, elevated water tanks were heavily damaged or collapsed during earthquake Hence different configurations of liquid storage tanks have been constructed. Water tanks are play an important role in municipal water supply and firefighting systems. Due to post earthquake useful desires, seismic safety of water tanks is most important. In the current study time history analysis of rectangular and circular elevated water storage tank were analyzed using SAP 2000 software. In this study the concrete baffle wall was used to reduce sloshing effect of the water tank. The tank responses such as maximum nodal displacement, base shear and result were compared for empty and full tank water fill condition. From IS 11682:1985provision when seismic loading is considered only two cases may be taken one is tank empty condition and other is tank full condition. Finally, study discloses the importance of suitable supporting baffle wall to remain withstand against heavy damages of circular and rectangular elevated water tanks during earthquake. As per IITK-GSDMA guidelines for seismic design of liquid storage tanks, hydrodynamic pressure for impulsive and convective mode was calculated.
Necessity/advantage of a tunnel, Classification of Tunnels,
Size and shape of a tunnel, Alignment of a Tunnel, Portals and Shafts,
Methods of Tunneling in Hard Rock and Soft ground, Mucking, Lighting
and Ventilation in tunnel, Dust control, Drainage of tunnels, Safety in
tunnel construction.
Comparative Study on the Design of Square,Rectangular and Circular Concrete W...IJERA Editor
Reinforced concrete overhead water tanks are used to store and supply safe drinking water. Design and cost estimation of overhead water tanks is a time consuming task, which requires a great deal of expertise. This study therefore examines the efficiency of Rectangular and Circular tanks. Tanks of 30m3, 90m3, 140m3 and 170m3 capacities were used in order to draw reasonable inferences on tank‟s shape design effectiveness, relative cost implications of tank types and structural capacities. Limit state design criteria were used for basic tank‟s construction materials- steel reinforcement, concrete and formwork were taken-off from the prepared structural drawings. Results of the material take-offs showed that, for each of the shapes, the amount of each structural materials increase as the tank capacity increases. Also Circular-shaped tank consumed lesser individual material as compared to Rectangular ones. Hence, this will give Circular-shaped tanks a more favoured selection over the rectangular shaped tanks.
Seismic analysis of water tank considering effect on time periodeSAT Journals
Abstract While comparing both IS 1893-1984 and IS 1893(part II), first section we consider effect of Seismic responses-base shear, base moment, direction of seismic force, effect of vertical ground acceleration, maximum hydrodynamic pressure, sloshing wave height and additional parameters which calculated using response spectra with change in staging height and performing a few simple calculations and graphs. Here we observe the effect on time period with reference to the staging height in same sample calculations and graph obtained for different quantity. And also collecting the actual site dimension’s (parameters) situated in Nagpur, for evaluation effect of staging height on earthquake forces and effect of soil type conditions on earthquake forces with constant zone, analyzing the tank in SAP2000 for stiffness at different staging height. And analysis has been done by both IS codes. This analysis shows the difference between the all the parameters. Keywords: IS 1893-1984, IS 1893(part II), SAP2000
A bridge is the key element in a transportation system; it controls both the volume and weight of the traffic. Balance must be achieved between handling future traffic volume and loads and the cost of heavier and wider bridge structure. Economic Analysis and comparisons against competing alternatives is required as Bridges are the most expensive part of a road transportation network. Monetized & Non-Monetized Benefits that will accrue like time savings to road users, benefits to business activities (and to the economy in general) and salvage value benefits like Right-of-Way and substructure use need to be assessed as well.
Seismic behavior of elevated water tankeSAT Journals
Abstract Hydrodynamic analysis of elevated water tank is a complex procedure involving fluid structure interaction. The elevated tank supports large water mass at the top of slender staging. In case of elevated tank the resistance against lateral forces exerted by earthquake is largely dependent of supporting system. Staging is considered to be a critical element as far as lateral resistance is concern. Satisfactory performance of staging during strong ground shaking is crucial. In this paper seismic behavior of elevated water tank in view point of their supporting system is evaluated using finite element software ETABS. The main objective is to evaluate a performance of different staging system for elevated water tank using finite element software ETABS. The spring mass model consisting of impulsive and convective masses as per IS 1893:2002 Part 2 has been used for the analysis. The parametric study is performed on mathematical model with different staging system to evaluate their performance with regard to lateral stiffness, displacement, time period, seismic base shear, overturning moment, flexure etc. Keywords: Hydrodynamic analysis, Staging Performance, spring mass model, ETABS
Concrete Gravity Dam Components
A gallery is a small passage in a dam for providing an access to the interior of the dam.
The gallery is usually rectangular in shape with its top and bottom either flat or semi circular.
For a gallery with its top and bottom flat, it is necessary that all the corners should be rounded. The width of gallery generally varies from 1.5 to 1.8 m. The height of the gallery in between 2.2 to 2.4 m, so that a person can easily walk inside it.
To provide drainage of the dam section.
2. To provide space for equipment required for drilling holes and grouting the hole to form a grout curtain in the foundation.
3. To provide space for header and return pipes for post cooling of concrete.
4. A gallery provide an access to the interior of the dam for inspection ard maintenance.
5. A Gallery also provides space for installing various instruments in the dam to study its structural behaviour.
6. A gallery can provide space for the mechanical and electrical equipment required for the operation of gates for spillways and outlets.
A shaft is a vertical opening provided in a dam. Shafts are required for locating headers of the post cooling system and for locating measuring devices.
Shafts are also required for the movement of elevators and the hoisting equipment. Sometimes shafts are constructed inclined to connect two galleries or the same gallery at two different elevations by a staircase or a lift arrangement.
A plumb line shaft is constructed at the maximum section of the dam to make observations of the deflection of the dam under loads.
A plumb bob is suspended by a wire fixed at the top of the shaft. As the dam deflects relative to the base, the plumb bob also moves by the same amount.
A stilling well shaft is a special shaft used to record fluctuations of the water level in the reservoir. The shaft is connected to the reservoir at a point below the minimum reservoir level.
There is a floating mechanism in the stilling well shaft which records fluctuations in the water level.
The spillway in a gravity dam is called overflow section. Spillway is provided to dispose of surplus water from the reservoir to the downstream.
Spillways are provided for all dams as a safety measure against overtopping and the consequent damages, and failure. spillway may be located either in the middle of the dam or at the end of the dam near abutment.
It must have adequate discharge capacity.
It must be hydraulically and structurally safe.
The surface of the spillway must be erosion resistant.
It should be provided with some device for the dissipation of excess energy
The portion of the gravity dam other than the spillway is a non-overflow section, a road is located on the non-overflow section of the dam.
At the one end of a gravity dam a power house is located. Water from the reservoir passes tnrough penstock and rotates the turbine provided at power elevations to produce electricity.
Water flowing over a spillway has a ver
The presentation summarizes the project work done on "Seismic Analysis of Elevated Water Tank". Elevated water tanks are important structures that serve the function of supplying municipal water to the civil community. The stability of such structure is highly uncertain in the eve of earthquake. This project analyses the performance of such a structure in the eve of earthquake.
The project is done as a course requirement for undergraduate degree in May 2013. The degree in pursuit was "Bachelor of Technology in Civil Engineering" in National Institute of Technology in Tiruchirappalli (INDIA). The authors were in final year of the study during the making of the project.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Preliminary Field Measurement of the Uniaxial Compressive Strength of Migmati...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Producing Bi- Layer Sportswear Using Bamboo And Polypropylene Knitted Fabrictheijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Design of a Digital Baseband Processor for UWB Transceiver on RFID Tagtheijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Multiband Circular Microstrip Patch Antenna for WLAN Applicationtheijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Differential Evolution Algorithm for Optimal Power Flow and Economic Load Dis...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Comparative Analysis on Sodium-Based and Polyethylene-Based Greases as Anti-F...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
A gravity dam is a solid structure, made of concrete or masonry, constructed across a river to create a reservoir on its
upstream. The section of the gravity dam is approximately triangular in shape, with its apex at its top and maximum width at bottom.
The section is so proportioned that it resists the various forces acting on it by its own weight. Most of the gravity dams are solid, so that
no bending stress is introduced at any point and hence, they are sometimes known as solid gravity dams to distinguish them from hollow
gravity dams in those hollow spaces are kept to reduce the weight. Early gravity dams were built of masonry, but now-a-days with
improved methods of construction, quality control and curing, concrete is most commonly used for the construction of modern gravity
dams.
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
DAMS
Types of dams
Selection of dam sites
Geological characters for investigation
Selection of the dam type
Gravity dams
butress dams
embankment dams
arch dams
cupola dams
composite dams
Bhakra Dam
Mir Alam multi-arch dam
Idukki Dam
Tehri Dam
Ujani Dam or bhima dam
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.
Seismic Analysis and Optimization of RC Elevated Water Tank Using Various Sta...IJERA Editor
As known from very upsetting experiences, poorly designed elevated water tanks were heavily damaged or
collapsed during earthquakes. This might be due to the lack of knowledge regarding the behaviour of supporting
system of the tank, and also due to improper selection of geometry of staging patterns. For certain proportions of
the tank and the structure, the sloshing of the water during earthquake may be one of the dominant
factors.Dynamic analysis of tank containing liquid is complex involving fluid-structure interaction.In this paper,
the seismic behavioural effect of circular elevated water tank is studied for specific capacity of tank for various
staging arrangements in plan, variation in number of periphery columns and variation in number of stages in
elevation. Two mass idealizations suggested by Gujarat State Disaster Management Authority are considered
here. Under earthquake loads; a complicated pattern of stresses is generated in the tanks. Total 36 combinations
were analysedwith SAP2000 using Response Spectrum Method (RSM) and results are presented. It is observed
that increase in number of columns, does not assure the increase in the improvement of structural responses.
Radial arrangement with six staging levels is found to be best for the number of columns used. To suggest
number of columns with suitable diameter cost optimization is done for the radial staging arrangement with six
staging levels consideringcritical direction of seismic force, quantity of concrete and steel required. It is found
that eight numbers of columns gives less cost as compared to six, ten and twelve with optimized diameter of
300mm.
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.
Understanding Inductive Bias in Machine LearningSUTEJAS
This presentation explores the concept of inductive bias in machine learning. It explains how algorithms come with built-in assumptions and preferences that guide the learning process. You'll learn about the different types of inductive bias and how they can impact the performance and generalizability of machine learning models.
The presentation also covers the positive and negative aspects of inductive bias, along with strategies for mitigating potential drawbacks. We'll explore examples of how bias manifests in algorithms like neural networks and decision trees.
By understanding inductive bias, you can gain valuable insights into how machine learning models work and make informed decisions when building and deploying them.
KuberTENes Birthday Bash Guadalajara - K8sGPT first impressionsVictor Morales
K8sGPT is a tool that analyzes and diagnoses Kubernetes clusters. This presentation was used to share the requirements and dependencies to deploy K8sGPT in a local environment.
HEAP SORT ILLUSTRATED WITH HEAPIFY, BUILD HEAP FOR DYNAMIC ARRAYS.
Heap sort is a comparison-based sorting technique based on Binary Heap data structure. It is similar to the selection sort where we first find the minimum element and place the minimum element at the beginning. Repeat the same process for the remaining elements.
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.
We have compiled the most important slides from each speaker's presentation. This year’s compilation, available for free, captures the key insights and contributions shared during the DfMAy 2024 conference.
1. The International Journal Of Engineering And Science (IJES)
|| Volume || 3 || Issue || 6 || Pages || 37-45 || 2014 ||
ISSN (e): 2319 – 1813 ISSN (p): 2319 – 1805
www.theijes.com The IJES Page 37
Feasibility Study of Bellary Nala Irrigation Project
Sreedevi R1
, Shreedhar R2
1
post Graduate Student, Department of PG studies ‘JNANA SANGAMA’ VTU Belgaum, Karnataka, India
2
professor, R Shreedhar Dept. of Civil Engineering, Gogte Institution of Technology, Belgaum, Karnataka India
-----------------------------------------------------------ABSTRACT-----------------------------------------------
Gravity dams are solid concrete structures that maintain their stability against design loads from the geometric
shape, mass and strength of the concrete. The purposes of dam construction may include navigation, flood
damage reduction, hydroelectric power generation, fish and wildlife enhancement, water quality, water supply,
and recreation. The design and evaluation of concrete gravity dam for earthquake loading must be based on
appropriate criteria that reflect both the desired level of safety and the choice of the design and evaluation
procedures. In India, the entire country is divided into 4 seismic zones, depending upon the severity of the
earthquake intensity. Thus, the main aim of this study is to design high concrete gravity dams based on the
U.S.B.R. recommendations in seismic zone II of India, for varying horizontal earthquake intensities from 0.10 g
- 0.30 g with 0.05 g increment to take into account the uncertainty and severity of earthquake intensities and
constant other design loads, and to analyze its stability and stress conditions using analytical 2D gravity
method. The vertical, principal and shear stresses are also obtained. Feasibility studies are carried out to
design a concrete gravity dam for horizontal earthquake intensity greater than 0.30 g without changing other
loads and or dimension of the dam and keeping provision for drainage gallery to reduce the uplift pressure
significantly.
KEYWORDS: Comparison; Concrete Gravity Dam; Dam Failure; Design; Earthquake Intensity, Stability and
Stress
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Date of Submission: 19 June 2014 Date of Publication: 30 June 2014
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I. INTRODUCTION
DAM
A hydraulic structure (fully impervious or fairly impervious) constructed across a river to store water
on its upstream side forming reservoir, which can be used at later stages. They are classified based on their use,
materials of construction and hydraulic design.
Classification based on use-
[1] Storage dam – it is the most general type of dam to impound water on upstream side during high flow in
rivers and used during the period of deficiency. They are constructed for various purposes like irrigation,
power generation, water supply etc. Storage dam maybe constructed of gravity, earth, rock fill and arch
dam.
[2] Diversion dam – these dams simply raise the water level in the river on its upstream side and provide
sufficient head for diverting water into ditches, canals and other conveyance system. It is of smaller height
and no water is stored on upstream side. Ex: weirs and barrages.
[3] Detention dam – they are constructed to store water during floods and release it gradually when flood
recedes. This will reduce the flood damage on downstream side. In some, situations, the water detained on
the upstream side in not released and held as long as possible. This detained water seeps through banks and
foundation strata, which help in increasing the water level of ground.
[4] Coffer dam – a coffer dam is a temporary dam constructed to exclude water from a specific area.
[5] Debris dam – a debris dam is constructed to catch and retain debris such as sand, gravel, silt and drift wood
flowing along with water in the river.
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Classification based on hydraulic design –
[1] Non- over flow dam – no over floe section is provided and crest of the dam will be higher than maximum
water level. Construction materials used are concrete, earth, rock fill, masonry.
[2] Over flow dam – it consists of an over flow section which discharges surplus water over its crest flowing
on downstream face. It is usually made of concrete so that the dam material is not eroded.
Classification based on material –
1. Rigid dams – they are constructed of rigid material such as masonry, concrete, steel or timber. They are
further classified as
A.Solid masonry or concrete gravity dam
B.Arched masonry or concrete dam.
C.Concrete bitterness dam.
D.Steel dam.
E.Timber dam.
Non rigid dam – non rigid materials such as earth and rock fill are used in these dams. Common types are
a) Earth dam.
b) Rock fill dam.
c) Combined earth and rock fill dam.
Classification based on structural behavior –
[1] Gravity dam – a gravity dam is a masonry or concrete dam which resists the forces exerted upon it by its
own weight. Its cross – section is approximately triangular in shape.
[2] Arch dam – an arch dam is a curved masonry or concrete dam, convex upstream, which resists the forces
exerted upon it, mainly by arch action.
[3] Buttress dam – a Buttress dam consists of a water retaining sloping membrane or deck on the upstream
which is supported by the series of the buttress which is generally in the form of equally based triangular
reinforced concrete or masonry walls.
[4] Embankment dam – an Embankment dam in a non – rigid dam, which resists the forces exerted upon it
mainly by its shear strength.
Classification based on size: The overall size classification for the dam would be greater of that indicated by
either of the following two parameters:
classification Gross storage Hydraulic Head
Small Between 0.5 and
10 million m3
Between 7.5 and
12m
Intermediate Between 10 and
60 million m3
Between 12 and
30m
Large Greater than 60
million m3
Greater than 30 m
II. LITERATURE REVIEW
Literature referred during the preparation of this thesis is mainly regarding the earthquake intensities,
effects of different shapes of galleries like rectangle, square, triangle and horse shoe. The research papers also
defines optimal top width and optimal shape of concrete gravity dam.
A.S. Shirkande V. B. Dawari describes the effect of openings is usually neglected in design of dam but it is
well thought out when openings are large. Large openings generate critical zones for tensile stresses in dam. The
work reported here comprise of analysis of dam with large openings. The limitations considered are size and
shape of large openings. Three models like without gallery, dam with regular size galleries and dam with large
inspection gallery are considered for comparing the effect of the size variation of inspection gallery on dam. The
effect of different shapes of galleries like rectangular, square, circular and horse shoe on stresses in dam is
studied for various locations. Overall square shaped inspection gallery gives minimum stress around gallery.
Due to large openings, there is increase in stresses around the openings and in the dam.
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It has been detected that large openings in the dam induce higher stresses in the vicinity of them. In some cases,
these openings have contributed up to fifteen to seventeen percent increase in stresses. The variation according
to different shapes is five to ten percent. However, square galleries show less increase in stresses as compared to
other shapes.
Farzin Salmasi study based on the design of a gravity dam is achieved through an interactive process
concerning a preliminary layout of the structure followed by a stability and stress analysis. This study presents a
method to define the optimal top width of gravity dam with genetic algorithm. To solve the optimization task
(minimize the cost of the dam), an optimization routine based on genetic algorithms (GAs) was executed into an
Excel spreadsheet. It was found to implement well and GA parameters were optimized in a parametric study.
Using the parameters found in the parametric study, the top width of gravity dam optimization was performed
and compared to a gradient-based optimization method (classic method). The accuracy of the results was within
close proximity. In optimum dam cross section, the ratio of dam base to dam height is almost equal to 0.85, and
ratio of dam top width to dam height is almost equal to 0.13. The computerized methodology may provide the
help for computation of the optimal top width for a wide range of height of a gravity dam.
In this study the design of gravity dam corresponding to the optimal top width can be approved for any required
height of the dam. The obtained design is the most economical and the safest in which no tension is created
anywhere in the dam section.
III. STUDY AREA
3.1. The river
Bellary nala originates near Yellur village in Belgaum taluk and is a tributary to Markandeya River.
The length of the nala up to its confluence with Markandeya river is 57 Km (36 miles). The Markandeya River
is a tributary of Ghataprabha River and in turn Ghataprabha River is a tributary of Krishna River. The catchment
area of Bellary nala up to proposed dam site is 253.82 Sq. Kms
.
3.2. History
The areas of Belgaum district through which the tributary of Krishna River flows, are in rain shadow
areas, where in annual rainfall is 740mm and is unevenly distributed. Even though the lands are fertile, they are
subjected to frequently occurring drought and scarcity conditions. In the absence of any other mineral resources,
and industrial development, the local population is dependent on rain fed agriculture. With the uncertain rainfall,
the farmers are depending on subsistence farming, resulting in low per capita income leading to poverty and low
contribution of GDP.In order to overcome the frequently occurring drought and scarcity, it was proposed to
construct an irrigation project across Bellary nala which is flowing in this region. Earlier, it was proposed to
construct a dam near Hudli village in Belgaum taluk and to feed water to Markandeya Right Bank Canal
(ongoing Project) by a link canal of 3 Km by gravity flow. Since the Bellary nala carries the Belgaum city
sewage water throughout the year, it was proposed to run the canal of Bellary nala project, parallel to
Markandeya Right Bank Canal up to the length of 90 Km where the Markandeya Right Bank Canal ends and
further up to 106.656 Km, to totally irrigate the lands coming under villages of Belgaum, Gokak, Bailahongal
and Soudatti talukas of Belgaum District.
3.3. Project proposal
It is proposed to construct Bellary nala project which provides, irrigation facilities to the lands of
Belgaum District coming under Belgaum, Gokak, Bailahongal and Soudatti talukas. Bellary nala carries the
Belgaum city sewage water throughout the year in addition to the rainfall run-off in the rainy season. The Nala
water is unsuitable for potable purposes as per test results, but it is suitable for irrigation purposes. Hence, it was
decided not to connect Bellary nala project canal to Markandeya Right Bank Canal, though the topography and
feasibility of the project, clearly favors for combining the two projects.
The Bellary nala project consists of, construction of reservoir across the Bellary nala at Karadikolla near Hudli
village, Belgaum Taluk, Belgaum District and canal network to supply water for irrigating the lands of,
Belgaum, Gokak, Bailahongal and Soudatti talukas.
3.3.1. Location of project
The proposed dam site across Bellary Nala is at Karadikolla near Hudli village, Belgaum Taluk,
Belgaum District. The latitude and longitude of the project are 15’58’ N and 74’38’ E respectively.
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3.3.2. Access to the project
The proposed dam site is approachable from Hudli village situated on Belgaum – Gokak road about 26
Km from Belgaum city. The project is also accessible through Airway as well as Railway since Belgaum city is
having Airport and Railway station.
3.3.3. Area benefited
The command area of this Project is 8,200 Ha, which covers the lands of Belgaum, Gokak, Bailahongal
and Soudatti talukas of Belgaum District.
IV. GRAVITY DAMS
The external forces such as water pressure, wave pressure, uplift, silt pressure etc are resisted by the
weight of the dam and hence it is called gravity dam. It is constructed of either masonry [small height, ex. KRS]
or concrete [large height ex. Hidkal] and may be straight or curved in plan. Most of the gravity dams are solid
and hence called solid gravity dam
Forces acting on gravity dam
Weight of the dam – this is the major resisting force, computed by considering 1m length of dam. It is the
product of cross – section area of dam section, 1m length and unit weight of dam material.
Waterpressure – it is the major external force, obtained as area of pressure diagram multiplied by length of
dam (1m). if the upstream face is vertical, then horizontal pressure fore is
P = acts at from base of dam.
On the other hand, if the face is inclined, an additional vertical water pressure acts as
P1 = Area of portion above inclined surface x 1x ϒw. Further, with tail water, P2 and P3 are also
considered as
P2 = acts at from base.
And P3 = area of portion EFG x 1 x ϒw
Uplift pressure – the upward pressure exerted by the water that seeps through the body of the dam and
through the pores and fissures of the foundation. As per USBR recommendations the intensity of uplift
pressure at toe and heel of dam is equal to static water pressure intensity. The drainage gallery provided in
the dam relieve the uplift pressure. The uplift pressure diagram is as shown in the diagram 4.1. The uplift
pressure force is computed by multiplying area of uplift pressure diagram with length of dam (1m).
Pressure due to earthquake : due to earthquake waves, acceleration are imparted to the foundations and make
them to move. To avoid rupture dam should also move along the foundation, which induce inertia force in the
body of the dam and sets up stress that move from lower layer to upper elevations. These accelerations are
resolved into horizontal and vertical components.
a) Effect of horizontal acceleration -
1. Inertia force in the body of the dam – it acts opposite to the direction of acceleration imparted by earthquake
and given by
F = Wα
Acting at centroid of respective portions.
2. Hydrodynamic pressure – the acceleration towards the reservoir induces rise in water pressure which varies
parabolic ally as in fig 1.1. The total pressure force
Pe = 0.555 α ϒw H2
Acting at from the base.
Zanger (1952) presented the formula for computing intensity of pressure derived by electrical analogy assuming
water as incompressible. The pressure variation is elliptic – cum – parabolic and intensity at any depth y below
MWL is
Pey = Cy α ϒw y Where Cy = dimensionless pressure coefficient at y below free surface
Cm = maximum value of pressure coefficient for a given constant slope = 0.735
Ө = inclination of upstream face with horizontal.
If the upstream side is inclined for a depth smaller than half of height of water storage then upstream face is
considered vertical (Ө = 90) and Cm = 0.735. However, when the upstream face is inclined for more than half
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the depth then Ө is obtained by considering modified slope with upstream face connected between MWL and
heel point. The pressure variation is considered elliptical – cum – parabolic.
Hence Pey = 0.726 pey y
And the moment about the toe
Mey = 0.299 pey y Effect of vertical acceleration – Due to vertical acceleration, vertical inertia force (αW) exerts
opposite to that of direction of acceleration. This alerts the weight of the dam.
Ice pressure : it is an important force to be considered when the dam is located in cold region or ay high
elevations. The ice formed on the water surface either expands or contracts depending upon the temperature
change. When the ice expands it exerts pressure on the upstream face of dam linearly along the length because
coefficient of thermal expansion of ice is 5 times that of concrete. The magnitude of ice pressure varies from 2.5
to 15 kg/cm2
. However, an average value of 5 kg/cm2
is considered under ordinary conditions.
Wave pressure -
Due to the wind blowing over the water surface, waves are generated which exerts pressure on the reservoir.
According to D. A. Molitor, the wave height hw is given by
For Fetch F < 32 Km,
hw = 0.032 + 0.763 – 0.271 and
For F > 32 Km hw = 0.032
Where hw is wave height in m, v = wind velocity in Kmph and F is fetch or straight length of water expanse in
Km.
The intensity of pressure, pw = 2.4 ϒw hw and total force Pw = 2000 hw
2
(Kg/m)
And acts at (= 0.375hw) above reservoir surface.
Silt pressure : the silt and debris deposited in the reservoir exerts silt pressure which can be determined as
Ps = ϒ1
h2
Where = angle of internal friction of silt.
ϒ1
= submerged unit weight of silt.
h = depth of silt deposition.
If the upstream face is inclined then in addition to above horizontal force, the vertical force shall also be
considered.
Wind pressure: it is a minor force and need hardly be considered. However, for the exposed area, the wind
pressure is taken as 100 to 150 Kg/m2
.
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LOAD COMBINATIONS FOR DESIGN
The design of a gravity dam is based on the most adverse combination of the loads (or forces) acting on
it, which includes only those loads having a reasonable probability of simultaneous occurrence. The
combinations of transient loads such as those due to maximum flood and earthquake are not considered because
the probability of occurrence of each of these phenomena is quite a low and hence the probability of their
simultaneous occurrence is almost negligible. Thus for the design of gravity dams IS; 6512-1984 specifies the
load combination A,B,C,D,E,F,G as indicated below.
a) Load combination A (Construction condition or Empty reservoir condition) Dam completed but no water in
reservoir and no tail water.
b) Load combination B (Normal Operating Condition) - Full reservoir elevation normal dry weather tail water,
normal uplift; ice and silt (if applicable).
c) Load combination C ( Flood Discharge Condition) - Reservoir at maximum flood pool elevation, all gates
open, tail water at flood elevation, nor-ma1 uplift, and silt ( if applicable ).
d) Load combination D - Combination A, with earthquake.
e) Load combination E - Combination B, with earthquake but no ice.
f) Load combination F - Combination C, but with extreme uplift (drains in operative).
g) Load combination G - Combination E, but with extreme uplift (drains in operative).
Stability analysis – modes of failure
1. Factor of safety against overturning.
2. Factor of safety against sliding.
3. Compression and tension.
Overturning:
The overturning of dam takes place when the resultant force passes through the downstream toe. On the other
hand, if the resultant cuts the base within the body of dam, no overturning occurs.
The factor of safety against overturning
= =
Sliding:
If the horizontal sliding forces are greater than resisting forces above any level, the dam may fail due to sliding
at that level. The resistance may be due to friction or due to friction and shear strength of joint. Shear strength is
developed due to proper bond at joints and at bended foundations.
The factor of safety against sliding without shear strength
=
Where = coefficient of friction = 0.65 to 0.75.
∑V = net vertical force.
And ∑H = net horizontal force.
Compression and tension –
The normal stress at any point on the base of the dam is obtained as,
Pn =
Where b = width of dam section.
∑V = net vertical force and
E = eccentricity = – x
X = =
Normal stress at toe, (pn) toe =
At heel, (pn) heel=
When the normal stress at toe, (pn) toe> f, allowable compressive stress of dam material, the material starts crush.
Hence, the effective width reduces.
On the other hand, when (pn) heel becomes tensile (-ve), tension cracks are developed, leading to failure of
dam.
The stresses depend on material strength and quality.
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Principle and shear stresses : An element considered at heel as shown in figure is subjected to water pressure
which acts perpendicular to the face without any tangential stress and hence it is normal stress on normal plane
AB called principle stress. As principal planes will be normal to each other, plane AC is also the principle plane
and the stress Ҽ1 acting on it is the principle stress.
Resolving the forces in vertical direction, if pe1 is intensity of hydrodynamic pressure then
At heel, ϭ1 = pn sec2
– (p + pe) tan2
At toe, ϭ1 = pn sec2
– (p - pe) tan2
similarly, resolving the forces in horizontal direction, considering
hydrodynamic pressure intensity,
At heel, Ҽ = [pn – (p + pe)] tan At toe, Ҽ = [pn – (p - pe)] tan
Elementary profile of a gravity dam
When the gravity dam is subjected to water pressure alone, the elementary profile will be a triangle with zero
width at top and maximum at base having the shape of hydrostatic water pressure diagram. When this dam
section is under reservoir empty condition, the resultant force passes through upstream middle third point M1.
However, under reservoir full condition the following forces are considered to arrive at elementary profile of the
dam.
(i) Weight of the dam W = w BH 20
(ii) Water pressure P = w H2
21
(iii) Uplift pressure U = CϒwHB 22
Where = specific gravity of dam material,
C = uplift pressure intensity coefficient.
Practical profile of a Gravity Dam
The practical profile includes – the roadway at top, additional load due to road, free board. These
provisions make the resultant force getting shifted towards the toe. To eliminate tension at heel, some masonry
is added on upstream face. The top width for roadway = a = 14% of height of dam.Freeboard = 1.5 times height
of wave above normal pool elevation or maximum reservoir level which ever gives highest crest elevation. The
freeboard above maximum reservoir level shall not be less than 0.9 m. further, while determining height of
wave, the wind velocity shall be taken as 120 Km/h over normal pool condition and 80Km/h over MWL.
Methods of design of gravity dams
The various methods used for the design of gravity dams are as follows.
[1] Stability analysis method
[2] Zone of determination of Profile of a dam.
Stability analysis method
In this method a trial section of the dam is first assumed on the basis of the previous designs,
experience, configuration of valley, etc. The stability of the assumed section is then checked at the foundation
level as well as at other levels. The various methods used for stability analysis are:
[1] Gravity method
[2] Trial load twist method
[3] Experimental method
[4] Slab analogy method
[5] Lattice analogy method
[6] Finite element method
Gravity method
In this method the dam is considered to be composed of a series of vertical cantilevers independent of
each other and the load acting on the dam is transferred to the foundation through cantilever action. For the sake
of convenience a cantilever of unit length contained between two vertical planes normal to the axis of the dam is
considered above the deepest foundation level and its stability is checked against all the possible modes of
failure. At the base of the dam as well as at various horizontal sections above the base. If necessary the assumed
dam section is modified and when a section satisfying the stability requirements is obtained the same is adopted
for the entire dam. The various steps involved in this method are as indicated below
a. Calculate all the forces acting per unit length of the dam considered above the deepest foundation level.
b. Find the horizontal and vertical components of all the forces.
c. Find Σ H the algebraic sum of all the horizontal forces and ΣV the algebraic sum of all the vertical forces.
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d. Find the moments of all the forces about the toe of the dam and compute ΣMO the sum of the overturning
moments and the ΣMR the sum of the righting moments. Also find the algebraic sum of all the moments
ΣM = (ΣMR- ΣMO)
e. Find the distance of the point of intersection of the resultant R with the base from the toe of the of the
dam using the relation
= (ΣM /ΣV)
f. Find the eccentricity e, which is the distance between the centroid of the area of the base when the point of
intersection of the resultant with the base, as given by the expression
e = (b/2) -
g. Find the normal stress at the toe as well as heel of the dam given by equation
σy= (ΣV / b) * (1 ± (6e/ b))
h. Find the principle and shear stresses at the toe and the heel of the dam given by previous equations.
i. Find the factor of safety against overturning by the expression
F.S = (ΣMR/ΣMO)
j. Find the factors of safety against sliding given by previous equations.
Design of gravity dam – multiple step method
The dam section is divided into seven zones and each zone is designed to satisfy the stability
requirements.
Zone I: It is the portion above maximum water level (or bottom of ice sheet, if exists). If there is no ice, the
height of zone I is governed by free board.
Zone II: this is the portion for which both upstream and downstream of dam are kept vertical. The position of
the bottom of the dam is obtained such that the resultant force with reservoir full passes through outer middle
third point. However, when reservoir is empty, resultant lies within middle third portion.
Zone III: In this zone,upstream face remains vertical, while downstream face is inclined. When the reservoir is
full, the resultant force continues to coincide with the outer middle third point. The height of the zone is
determined when the resultant with reservoir empty passes through inner middle third point.
Zone IV: In this zone, both upstream and downstream faces are inclined, so that the resultant coincides both
extreme middle third points under respective conditions. The height of the zone is governed by the criterion that
the maximum inclined pressure at downstream face for reservoir full condition is just equal to allowable limit.
The height and upstream and downstream slopes of this zone is determined by trial, dividing the zone into
several blocks. Low dam lie within the limit of zone IV.The dam designed in this study is assumed with a top
width of 7.5 m (two lane). After initial calculations the height for Zone 1 (free board) is fixed as 2.5 m. by trial
and error the height for zone II is decided as 5.4 m with the base width of 7.5 m. with this Zone III is designed
by making blocks of 3 mtr height and downstream slope is decided accordingly and zone III has 13.5 m height
with the base width of 16.71 mtrs. Zone IV has got both the upstream and downstream slopes, here the blocks
are of 5 mtr height. Finally height for zone IV is 13 mtrs. As the dam we designed is a low dam (<45 mtrs) so
the height is 40.4mtrs with the base width of 38.65 mtrs. Tail water is provided at the height of 8 mtrs at the
downstream side and drainage gallery is fixed at 6.5 mtrs from the heel for the practical profile of the gravity
dam with the intensity of 0.1g. Thus the stability of the dam is safe for this conditions up to 0.15g with the
upstream slope as 0.15:1 and downstream slope 0.88:1.
V. METHODOLOGY
When a solid gravity dam is to be designed for an irrigation project, initially its elementary profile
(triangular section) is decided.
Then the elementary profile is modified to suit the practical conditions. These conditions are
1) A suitable freeboard is provided to prevent overflow
2) A suitable top width is provided for inspection and conveyance purpose.
Due to such provisions the weight of the dam increases at the top portion, which creates instability of the
section in reservoir empty condition and tension may be developed at the toe.
Hence it becomes necessary to increase weight on the upstream side and hence a batter is provided on the
upstream side.
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But for reservoir full condition, the resultant of all the forces remains in the middle third portion and the
section becomes quite safe. Hence to provide economy, the material from the downstream side may be
removed.
The addition of the quantity of material on the upstream and deduction of quantity of material from the
downstream are the function of top width of the section.
The net cross-sectional area of the dam is determined at a particular value of top width.
The section, for which the net cross-sectional area of the dam is minimum, is known as the optimal section.
The top width is taken as the function of the height of the dam.
The preparation of a simplified computerized method using MS-Excel is used to determine the optimal
section of the dam. The computerized methodology provides computation of the optimal section for a wide
range of height of a gravity dam.
This methodology also provides computation of the optimal section for a wide range of top width of a
gravity dam.
This methodology helps us to choose the optimal section by calculating the areas of concrete of various
sections i.e. the section with minimum area of concrete is the optimal section.
VI. OBJECTIVES:
[1] To carry out multiple step method of design.
[2] To decide optimum location of drainage gallery to reduce the uplift pressure.
[3] Back water calculations due to construction of the dam.
[4] To design concrete gravity dam for varying horizontal earth quake intensities from 0.1g to 0.3g with 0.05g
increment to take into account the uncertainty and severity of earthquake intensities.
VII. CONCLUSION
This study assures the stability of the dam at each blocks. Afterall the calculations, we make sure that
eccentricity e is less than or equal to b (base width)/6. The dam can resist the earthquake intensity up to 0.15g.
REFERENCES
[1] S. K. Garg, “irrigation engineering and hydraulic structures,” 18th edition, Khanna publishers, Delhi, 2004.
[2] IS: 6512-1998, Indian Standard “Criteria for design of solid Gravity Dams”
Farzin Salmasi- “Design of Gravity Dam by Genetic Algorithms” (International Journal of civil and Environmental engineering 3:3
2011).
[3] P.N. Modi “Irrigation water Resources and Water Power Engineering”, “8th
addition, Rajsons Publications Pvt. Ltd.
BIOGRAPHIES
Sreedevi R Post graduation
Student (M.Tech) in water and Land
Management in”JNANA SANGAMA”
VTU Belgaum
R Shreedhar is working has Professor,
Department of Civil Engg, Gogte Institute
Of Technology, Belgaum