Its about Bridge Component and Dam technique.
Full information about Bridge Construction.
Full information about construction of dam.
Training report. in pdf file
A RCC bridge is a monolithic structure that is poured in place. Forms are placed, the reinforcing steel is placed into the forms and a concrete mix is poured into the forms. The rebar extends beyond the form to allow connection to the next section to be poured. In a PSC structure the elements are precast either in a yard or onsite. They are cast with longitudinal holes to allow the prestressing strands to be extended between them. These strands use their tension to pull the units together and to act as reinforcement by prestreeing the entirety of the structure to make it stronger.
A RCC bridge is a monolithic structure that is poured in place. Forms are placed, the reinforcing steel is placed into the forms and a concrete mix is poured into the forms. The rebar extends beyond the form to allow connection to the next section to be poured. In a PSC structure the elements are precast either in a yard or onsite. They are cast with longitudinal holes to allow the prestressing strands to be extended between them. These strands use their tension to pull the units together and to act as reinforcement by prestreeing the entirety of the structure to make it stronger.
This is a powerpoint presentation on summer training from public works department. This presentation will be very helpful for civil engineering students.
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.
Study on Soil-Foundation Interaction under a Bridge Pierijtsrd
This study focuses on the behaviour of soil-foundation interaction under a bridge pier. In 2016, August 25, a magnitude of 6.8 happened near Bagan region. Pakokku Bridge, the longest of the bridges over the Irrawaddy, is situated on 37.8 miles from the epicentre of 2016 Chauk earthquake. That is why the safety performance of long-span Bridge especially for the safety of the foundation system subjected to soil-foundation interaction is necessary to investigate for static and seismic excitation. So, study on the behaviour of soil-foundation interaction under Bridge pier in static condition is presented in this study. Firstly super structural loadings on the pile cap are estimated by using STAAD PRO V8i. And then, theoretical ultimate soil resistance pcr and pcd due to wedge and flow failure are determined to produce critical depth xcr. Based on the value of critical depth, p-y curves are generated by Reese 1974 method for the static condition. After that, finite element software ABAQUS is used for the analysis of soil-foundation interaction under a bridge pier. In this study, the behaviour of soil-foundation interaction such as deflections, settlements, shear stresses and shear strains are produced. According to the analysis results, it is found that the vertical and horizontal displacements at the pile tip are 1.27mm and 4.68mm respectively. Maximum shear stress and strain are found out the base of the pile cap. Finally it is found that the soil-foundation interaction under a bridge pier presented in this study is reliable and reasonable with the limitation of AASHTO Standard Specifications for Highway Bridges. Zin May Hnin | Nyan Myint Kyaw | Kyaw Kyaw "Study on Soil-Foundation Interaction under a Bridge Pier" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-1 , December 2018, URL: http://www.ijtsrd.com/papers/ijtsrd19008.pdf
http://www.ijtsrd.com/engineering/civil-engineering/19008/study-on-soil-foundation-interaction-under-a-bridge-pier/zin-may-hnin
This is a powerpoint presentation on summer training from public works department. This presentation will be very helpful for civil engineering students.
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.
Study on Soil-Foundation Interaction under a Bridge Pierijtsrd
This study focuses on the behaviour of soil-foundation interaction under a bridge pier. In 2016, August 25, a magnitude of 6.8 happened near Bagan region. Pakokku Bridge, the longest of the bridges over the Irrawaddy, is situated on 37.8 miles from the epicentre of 2016 Chauk earthquake. That is why the safety performance of long-span Bridge especially for the safety of the foundation system subjected to soil-foundation interaction is necessary to investigate for static and seismic excitation. So, study on the behaviour of soil-foundation interaction under Bridge pier in static condition is presented in this study. Firstly super structural loadings on the pile cap are estimated by using STAAD PRO V8i. And then, theoretical ultimate soil resistance pcr and pcd due to wedge and flow failure are determined to produce critical depth xcr. Based on the value of critical depth, p-y curves are generated by Reese 1974 method for the static condition. After that, finite element software ABAQUS is used for the analysis of soil-foundation interaction under a bridge pier. In this study, the behaviour of soil-foundation interaction such as deflections, settlements, shear stresses and shear strains are produced. According to the analysis results, it is found that the vertical and horizontal displacements at the pile tip are 1.27mm and 4.68mm respectively. Maximum shear stress and strain are found out the base of the pile cap. Finally it is found that the soil-foundation interaction under a bridge pier presented in this study is reliable and reasonable with the limitation of AASHTO Standard Specifications for Highway Bridges. Zin May Hnin | Nyan Myint Kyaw | Kyaw Kyaw "Study on Soil-Foundation Interaction under a Bridge Pier" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-1 , December 2018, URL: http://www.ijtsrd.com/papers/ijtsrd19008.pdf
http://www.ijtsrd.com/engineering/civil-engineering/19008/study-on-soil-foundation-interaction-under-a-bridge-pier/zin-may-hnin
Analysis of Deck Bridge with Pre Stress Deck Bridge under IRC Loading Conditi...ijtsrd
A bridge deck is the portion of a bridge that acts as the roadway in the support of vehicular or pedestrian traffic. While deck parts like trusses, girders, rails, arches, posts and cantilevers assume a number of forms and types, there are relatively few bridge deck types given the utilitarian nature of the component. Deck types are defined by the materials from which they are made and the manner in which those materials are fit together. Yogesh Kanathe | Nitesh Kushwaha "Analysis of Deck Bridge with Pre-Stress Deck Bridge under IRC Loading Conditions a Review" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-6 , October 2019, URL: https://www.ijtsrd.com/papers/ijtsrd29636.pdf
https://www.ijtsrd.com/engineering/civil-engineering/29636/analysis-of-deck-bridge-with-pre-stress-deck-bridge-under-irc-loading-conditions-a-review/yogesh-kanathe
Analysis of PSC Bridge for Highway Structures using Softwareijtsrd
Bridge is most useful structure for highway Structures and River and Canal structures in without any obstruction of water, traffic is flow out on structures. In Bridge structures many sort of vehicles like little vehicles, light vehicles and substantial vehicles are streaming in inevitably, so primary idea of bridge is the manner by which to end up a safe under different kinds of stacking state of vehicles in a single bearing. By and large the vehicles are stream in structure, the heap of vehicles are Both side scatter in 45 degree from edge of feel burnt out on vehicle in both longitudinal and parallel bearings implies ranges heading and length of Structure headings. So this scattering of load is specifically influenced to best of bridge Deck section and after that longitudinal support and in addition cross brace. After that the long individual from bridge superstructure like brace is transported the heap towards the substructure of Bridge and afterward establishment to soil. The plan of superstructure is by and large utilized with RCC, however nowa days in length range individual from Bridge utilizing with PSC, forget significantly more preferred standpoint and security of Structure. Nitin Singh Raghuwanshi | Abhay Kumar Jha | Barun Kumar "Analysis of PSC Bridge for Highway Structures using Software" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-6 , October 2021, URL: https://www.ijtsrd.com/papers/ijtsrd47576.pdf Paper URL : https://www.ijtsrd.com/engineering/civil-engineering/47576/analysis-of-psc-bridge-for-highway-structures-using-software/nitin-singh-raghuwanshi
Larsen and Toubro (Lucknow Metro Project) Summer Internship PresentationShuBham RaNa
Hello Friends Myself SHUBHAM RANA . I am pursuing B.Tech in Civil Engineering from IIT ROORKEE. This is the glimpse of my work and basic aspects which I learned while doing my Internship in Larsen and Toubro Heavy Civil Infra IC. Thank You :)
Design and Analysis of a Girder Bridge for Highway Structures Using Sap 2000ijtsrd
In this study, a comparative study supported two differing types of bridges i.e. Deck type and Pre stressed deck type using finite element analysis in SAP 2000 is ready , considering same loading class 70 R as per I.R.C. loading. During this study well also prepare a price analysis of both the structures using S.O.R. C.P.W.D. 2014. This sort of bridges is more preferred when it involves connectivity to short distances. So, its necessary to update the analysis and style methods. Here, during this paper, theres an effort to review the comparison of maximum bending moment thanks to super load during a girder and slab bridge an equivalent bridge is analyzed as a three dimensional model in finite element software as SAP2000, apply an equivalent loading finished conventional methods and compared the results. The utmost bending moment results obtained from finite element model. Nitin Singh Raghuwanshi | Abhay Kumar Jha | Barun Kumar "Design and Analysis of a Girder Bridge for Highway Structures Using Sap 2000" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-6 , October 2021, URL: https://www.ijtsrd.com/papers/ijtsrd47575.pdf Paper URL : https://www.ijtsrd.com/engineering/civil-engineering/47575/design-and-analysis-of-a-girder-bridge-for-highway-structures-using-sap-2000/nitin-singh-raghuwanshi
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.
NUMERICAL SIMULATIONS OF HEAT AND MASS TRANSFER IN CONDENSING HEAT EXCHANGERS...ssuser7dcef0
Power plants release a large amount of water vapor into the
atmosphere through the stack. The flue gas can be a potential
source for obtaining much needed cooling water for a power
plant. If a power plant could recover and reuse a portion of this
moisture, it could reduce its total cooling water intake
requirement. One of the most practical way to recover water
from flue gas is to use a condensing heat exchanger. The power
plant could also recover latent heat due to condensation as well
as sensible heat due to lowering the flue gas exit temperature.
Additionally, harmful acids released from the stack can be
reduced in a condensing heat exchanger by acid condensation. reduced in a condensing heat exchanger by acid condensation.
Condensation of vapors in flue gas is a complicated
phenomenon since heat and mass transfer of water vapor and
various acids simultaneously occur in the presence of noncondensable
gases such as nitrogen and oxygen. Design of a
condenser depends on the knowledge and understanding of the
heat and mass transfer processes. A computer program for
numerical simulations of water (H2O) and sulfuric acid (H2SO4)
condensation in a flue gas condensing heat exchanger was
developed using MATLAB. Governing equations based on
mass and energy balances for the system were derived to
predict variables such as flue gas exit temperature, cooling
water outlet temperature, mole fraction and condensation rates
of water and sulfuric acid vapors. The equations were solved
using an iterative solution technique with calculations of heat
and mass transfer coefficients and physical properties.
6th International Conference on Machine Learning & Applications (CMLA 2024)ClaraZara1
6th International Conference on Machine Learning & Applications (CMLA 2024) will provide an excellent international forum for sharing knowledge and results in theory, methodology and applications of on Machine Learning & Applications.
Internship Report on Bridge Construction & Dam Construction
1. TRAINING REPORT
(TRAINING DURING : 21 JAN–20 MARCh2019 )
( GUIDED BYMR. AdityaNarayanChaudhry )
RIDDHI SIDDHI HIGH LEVEL BRIDGE
By
KESHAV CONSTRUCTION AUTHORITY (KCA),
Ram Kishor Vyas Bhawan, Indra Circle,
Jawaharlal Nehru Marg,
Jaipur (302004) Rajasthan, India
Submitted by :
Nikhil Kumar
MRT16UGBCE002
Department of Civil
Engineering SHOBHIT
DEEMED UNIVERSITY,
MEERUT
2. ACKNOWLEDGEMENT
I would like to thank Keshav Construction Authority(KCA) for giving me this
invaluable opportunityto learn so much practical knowledge which would have
impossible to learn through onlylooking at images from textbooks. I have gained
invaluable insights into how construction of any superstructureis handled and how
any difficultywhich comes in between is tackled. Apartfrom technical knowledge, I
have gain insights into construction management, efficientman-power
managementand lots of other thing.
I am deeply indebted to our training in-chargeat site Mr. Aditya Narayan
Chaudhry. whose help, stimulating suggestions and encouragementhelped me in
all the time at the training site and also for writing this training report. Also I am
thankfulto Mr.
Manish Jangid and Mr. BharatSingh for helping me understand the processof
construction.
My colleagues from the Civil Engineering Departmentsupported me in my project
work. I want to thank them for all their help, support, interestand valuable hints
Especially, I would like to give my special thanks to my parents whose patient love
enabled me to complete this work. And at last butnot the least I would like to
thank God for the successful completion of my project.
3. CONTENTS
1. INTRODUCTION
2. DETAILS OF BRIDGE
3. BRIDGE COMPONENTS
PILE FOUNDATION
PILE & PILECAP
SUBSTRUCTURES
PIER &PIER CAP , PEDESTAL,BEARING, ABUTMENT
SUPERSTRUCTURES
GIRDER, SLAB , CRASHBARRIER
4. DAM construction
1 Introduction
2 General Data in 2000
3 The Purpose of Dams
4 Dam Design and Construction
4.1 General comments
4.2 Earthfill dams
4.3 Rockfill dams
4.4 Gravity dams
4.5 Arch dams
4.6 Other dams
4.7 Foundations
4.8 Floods through dams: spillways
5 The Environmental and Social Impact of Dams
6 The Future of Dams
4. INTRODUCTION
Seeing the current increase in the traffic conditions and water logging problem during the rainy
seasons at Amanishah Nullah, Jaipur Development Authority (JDA) has bagged the contract to
PRL For Bridge over Amanishah Nulluh.
The bridge is constructed 536m over Amanishah Nullah. The bridge which will connect the Vijay
Path Junction to Shipra Path, Mansarovar, Jaipur. It is expected to reduce the pressure of high
traffic coming straight to the city.
The type of bridge that is been constructed over ken river is known as girder bridge. A girder
bridge in general is a bridge that uses girders as the means of supporting the deck. A bridge
consists of three parts: the foundation (foundation and piers), the superstructure (girder,slab),
and the deck.
Solid slab and deck slab with girders are used in bridge. The bridge is made of concrete and
steel. Girders are casting at site itself. Prestressed girders are used.
Due to high traffic it was decided that finish first one side with parallel work on the other side.
5. DETAIL OF BRIDGE
6 Lane and 2 Way Bridge.
Lengthof Bridge = 536 m.
RCC Part of Bridge= 27m.
Approach /Earthwork (filled) =266m.
Carriageway= 3.5*3= 10.5m.
Total Widthof Bridge = 2*( Carriageway= 10.5m) + 2*( CrushBarrier= 0.45m) +
2*(Footpath=1m) + 2*( Median= 0.3m ) = 24.5m.
FootpathProvidedinbothsides.
Types of Slabsused:
1. 11.4m SpanSolidSlab:12.25m*11.4m
2. 20mSpan DeckSlab :12.25m*20m
Foundation :Pile Foundation
1. FourPilesGroup ( ForSolidSlab) : Dimension =5.1m*5.1m.
2. Six Piles Group( ForDeckSlab) : Dimension =5.1m*8.7m.
GirderUsed: PrestressedConcreteGirderof 20mSpan.
Bearing:ElastomerBearingwithDimension=250mm*400mm.
Pedestal :Dimension550mm*700mm.
Diameterof Pile =1.2m.
Diameterof Pier =2.2m.
Properties ofSoil:
C=0, phi >= 30 Degree
Gama =1.80t/(m^3)
6. Grade of Concrete Used
PILE & PILE CAP : M35
PIER & PIER CAP, MEDIAN WALL: M40
APPROACH SLAB M40
CRASHBARRIER, PEDESTAL M40
PSC GIRDER M45
SOLID SLAB M45
7.
8. FOUNDATIONDESIGN
PILE FOUNDATION: Diameter= 1.2m and Depth =25m.
Piledfoundations :
General descriptionsof pile typesThere isalarge varietyof typesof pile usedforfoundationwork.The
choice dependsonthe environmentalandgroundconditions,the presenceorabsence of groundwater,
the functionof the pile,i.e.whethercompression,upliftorlateral loadsare tobe carried,the desired
speedof constructionandconsiderationof relative cost.The abilityof the pile toresistaggressive
substancesororganismsinthe ground or insurroundingwatermustalsobe considered.InBS8004,
pilesare groupedintothree categories:
(1) Large displacementpiles:these includeall solidpiles,includingtimberandprecastconcrete and steel
or concrete tubesclosedatthe lowerend bya shoe or plug,whichmaybe either left in place or
extruded toformanenlargedfoot.
(2) Small displacementpiles:these include rolled-steel sections,open-endedtubesandhollow sections
if the groundenters freely duringdriving.
(3) Replacementpiles:these are formedbyboringorothermethodsof excavation;the borehole maybe
linedwithacasingortube thatiseitherleftinplace orextractedasthe holeisfilled.
Drivenand cast-in-place piles : These are widelyusedinthe displacementpilegroup.A tube
closedat itslowerendbya detachable shoe orby a plugof gravel or dry concrete isdriventothe
desiredpenetration.Steelreinforcementislowereddownthe tube andthe latteristhenwithdrawn
duringor afterplacingthe concrete.These typeshave the advantagesthat:(1) the lengthcanbe varied
readilytosuitvariationinthe level of the bearingstratum;(2) the closedendexcludesgroundwater;(3)
an enlargedbase canbe formedby hammeringoutthe concrete placedatthe toe; (4) the
reinforcementisrequiredonlyforthe functionof the pile asafoundationelement,i.e.notfrom
considerationsof liftinganddrivingas forthe precastconcrete pile;and( 5) the noise andvibrationare
not severe whenthe pilesare drivenbyadrophammeroperatingwithinthe drive tube.Drivenand
cast-in-place pilesmaynotbe suitable forverysoftsoil conditionswhere the newlyplacedconcretecan
be squeezedinwardsasthe drive tube iswithdrawncausing'necking'of the pile shaft,noristhe
uncasedshaftsuitable forgroundwhere waterisencounteredunderartesianheadwhichwashesout
the cementfromthe unsetconcrete.These problemscanbe overcome byprovidingapermanent
casing.Ground heave candamage adjacentpilesbefore the concrete hashardened,andheavedpiles
cannot easilybe redriven.However,thisproblemcanbe overcome eitherbypreboringorbydrivinga
numberof tubesina groupinadvance of placingthe concrete.The latterisdelayeduntil pile drivinghas
proceededtoa distance of at least6.5 pile diametersfromthe one beingconcretedif small (upto3mm)
upliftispermitted,or8 diametersawayif negligible (lessthan3mm) upliftmustbe achieved.22The
lengthsof drivenandcast-in-place pilesare limitedbythe abilityof the drivingrigstoextractthe drive
tube and theycannotbe installedinverylarge diameters.Theyare unsuitable forriverormarine works
unlessspeciallyadaptedforextendingthemthroughwaterandcannotbe driveninsituationsof low
headroom.
9. Estimating Pile Capacity :
The ultimate load-carryingof apile isgivenbyasimple equationasthe sumof
the loadcarried at the pile pointplusthe total frictional resistance ( skinfriction) derivedfromthe soil-
pile interface.
Qu = Qp+ Qs
Where
Qu = ultimate pilecapacity
Qp = load-carryingcapacityof the pile point
Qs = frictional resistance
Pile Groups:
Pile groupsare usedto transmitthe structural loadto the soil.A pile cap isconstructed
overgroup piles.The pile groupcanbe contact withthe ground,or well above the ground.
Determiningthe load-bearingcapacityof grouppiles.
Whenthe pilesare placed close toeach other,a reasonable assumptionisthatthe stresstransmittedby
the pilestothe soil will overlap,reducingthe load-bearingcapacityof piles.Ideally,the pilesingroup
shouldbe spacedsothat the load-bearingcapacityof the groupshouldnotbe lessthanthe sumof
bearingcapacityof the individual piles.Inordinarysituationscenter-to-centerpile spacingis3 – 3.5D.
In our designitistaken3D = 3 *1.2m = 3.6m
The efficiencyof the load-bearingcapacityof a grouppile maybe definedas
Ƞ=Q g(u) /(∑Qu)
Where Q g(u) = ultimate load-bearingcapacityof the grouppile
Q (u) = ultimate load-bearingcapacityof eachpile withoutthe groupeffect
14. Pierand PierCap :
A supportof concrete ormasonryforsuperstructure ofbridge.
The base of piermayrestdirectly overfirmroundoritmaybe supportedonpiles.
Centre line of pier normallycoincidewiththe centerline of the superstructure.The
dimension of the topof pierdepends ondistance betweengirder(longitudinal girder) and
distance required toprovidefortheexpansion ofgirder, sizeof bearingetc.
15.
16. Pedestal :
Pedestal ismade of RCCAndconnectingto piercap.The grade of concrete usedfor
pedestal isM40. The size of pedestal is550mm*700mm as givenbelow.
17. Bearing : ( UsedElastomer Bearing inour case )
Bearingisa componentof a bridge whichtypically providesarestingsurface between
bridge piersandthe bridge deck.The purpose of a bearingisto allow controlledmovementand
therebyreduce the stressesinvolved.Movementcouldbe thermal expansionorcontraction,or
movementfromothersourcessuch asseismicactivity.There are several type of bridge bearings
whichare useddependingonanumberof differentfactorsincludingthe bridge span.The oldest
formof bridge bearingissimplytwoplatesrestingontopof each other.A common formof modern
bridge bearingisthe elastomericbridge bearing.Anothertype of bridge bearingisthe mechanical
bridge bearing.
f
18. ABUTMENTS
An abutment is a structure that support one end of a bridge in other word we can say that it is
structure located at the end & at the beginning of a bridge.
Functions of abutment
a) Support the bridge deck at end.
b) Retainthe embankment of approaching road.
c) Connected the approach road to the bridge deck.
19. SUPERSTRUCTURE
GIRDERS: 20M SPAN GIRDERS
MAIN GIRDER: These are the strong beams that carry load from superstructure to the substructure.
A girder is a support beam used in construction. It is the main horizontal support of a
structure. Girders often have an I-beam cross section composed of two load-bearing flanges
separated by a stabilizing web. In our case girders were Prestressed girders. Girders were
casted at site.
20.
21. END CROSS GIRDER:
The primary function of cross girders is to support the deck slab. The
girders may however need to perform secondary function of preventing the slab from
buckling in compression. Typically these are the transverse beams ( also very strong / stiff )
which are provided for transverse stiffness. This transverse diaphragm will make sure that if
you have multiple main girders, they share loads between them and don’t behave
independently.
22. DECK SLAB
The principal function of a bridge deck slab is to provide support to local vertical loads
(from highway traffic, railway or pedestrians ) and transmit these loads to the primary
superstructure of the bridge.
As a result of its function, the deck will be continuous along the bridge span and ( apart
from some railway bridges ) continuous across the span. As a result of this of this
continuity, it will act as a plate ( isotropic or orthotropic depending on construction ) to
support local patch loads.
24. collidingwithdangerousobstaclessuchasboulders,wallsorlarge stormdrains.Crashbarriersare
alsoinstalledatthe roadside topreventerrantvehiclesfromtraversingsteepslopes.Crashbarriers
are normallydesignedtominimizeinjurytovehicle occupants,injuriesdooccurin collisionswith
crash barriers.Theyshouldonlybe installedwhere acollisionwiththe barrierislikelytobe less
severe thancollisionwiththe hazardbehindit.
To make sure theyare safe and effective,crashbarriersundergoextensive simulatedandfull scale
crash testingbefore theyare approvedforgeneral use.While crashtestingcannotreplicateevery
potential mannerof impact,testingprogramsare designedtodetermine the performance limitsof
crash barriersand provide anadequate level of protectiontoroadusers.
25. Cofferdams 101: Different Types and
Construction Methods on Waterways
Working around water poses a plethora of challenges. There are always two parts of a water-
based project, the above and below water sections. Access to the above water section is easy,
however when working below the waterline access is not that easy. One of the more apparent
issues is what do you do when the water is in the way of your work? One solution is to build a
cofferdam.
What is a Cofferdam?
A cofferdam is a structure that retains water and allows a work area to be dewatered so that
crews can pour concrete, excavate, repair, weld, etc.
Types of Cofferdams
There are numerous configurations, sizes, and material options when it comes to cofferdams.
Below are a few examples:
Box-Type
Braced
Double-walled sheet pile
26. Cellular
Earthen
Single-walled sheet pile
Portadam™ Systems
Cofferdams can be customized to fit the needs of any project. Each of these systems has their
pros and cons, depending on conditions such as site location, site conditions, and price
restrictions.
Below we take a look at three types of cofferdams, their construction, and applications:
A Deeper Dig into Cofferdams
Braced Cofferdams
Braced cofferdams are made by vertically driving a single wall of sheet pile around the work area.
This type of cofferdam is typically driven into the shape of a box. Struts, or beams, then brace the
walls to keep them from collapsing inward, which is where it gets its name. When dewatered, a
cofferdam will withstand the force of the water while allowing crews access to the work area. This
cofferdam is an excellent choice for bridge pier and abutment repairs. These cofferdams may form
confined space work conditions, so it is imperative that they are sized correctly for all the tasks
that need to be accomplished for the project. Emergency evacuation should also be planned as it
can be very difficult to remove an injured person from a deep, confined space.
27. Cellular Cofferdams
Cellular cofferdams are typically used on larger scale projects, and
construction can be a major undertaking. A cellular cofferdam often serves
to provide a large work area.
Constructing a cellular cofferdam is done by driving sheet piles in a circular pattern, and then
repeating this process adjacent to the original to form a series of circular cells.
Each of these cells connects to one another and forms a tight seal that prevents water from
entering.
There are two types of cellular cofferdams, diaphragm and circular. Diaphragm types are
cofferdams with circular arcs at the sides, connected to straight diaphragm walls.
28. Circular types are large circle-shaped cells, connected to one another by slightly smaller circular
cells. Projects, where cellular cofferdams come into play, include dam construction projects,
barrier walls, and dock facilities.
Cellular cofferdams can be left in place as permanent structures. They can also provide crane
access to different areas of the work site if a road is built across the top.
29.
30. Portadam™ Systems
A unique temporary cofferdam option is implementing a Portadam™ system. What sets Portadam™ apart
from typical cofferdams is there is no ground penetration required for installation, “thereby minimizing
subsurface risk (environmental, cost, and schedule) usually associated with sheet piling.”*
The frames of the Portadam are assembled and placed on the river or lake bed, framing and enclosing the
area that needs to be dewatered. A vinyl fabric membrane and impervious fabric sealing sheet are then
placed over the frames and onto the bed, securing the area and allowing the dewatering process to occur.
As the units currently reach up to 12 feet high, in areas where the water will not be that deep,
a Portadam™ is a potential solution. In our experience, this can be a great solution for low-cost, temporary
access to work areas in slack water.
One must be very careful if using this in rivers or lakes that have strong currents, drastic fluctuations in
water levels, ice, or wind seiches.
31. Staying Safe
There are many risks involved in installing and maintaining an effective cofferdam such as ice flows,
current, vessel traffic, rock fissures, flood events, soil conditions and more. When working inside a
cofferdam, crews are often in a confined space, meaning an emergency response plan is a must. For the
cofferdam itself, maintaining an effective dewatering plan is crucial for successful project completion. By
having effective seals and dewatering systems with backups, you can make the difference between the
success and failure of a project.
A Tried & True Method
Working around water is going to be an ever-present hurdle for contractors. Fortunately, cofferdams are
around to offer a practical, proven method for selectively and temporarily removing water from the work
area. Understanding which type of cofferdam is best as well as knowing their strengths and limitations will
allow you to complete your project safely and on time.
32. Soil Investigation for Construction of Bridges and Culvert
The construction of culvert employs a simple soil investigation. Based on the type of foundation
proposed, the depth to which the investigation is carried out is decided by the engineer.
It involves the planning about the level up to which the foundation is to be taken and the anticipated
velocity of the flowing water during floods. The anticipation of any sort of deep scour will result in
the contradiction for pipe and the box culverts.
Areas where a pier or an abutment is proposed, a trial pit is made at the location. This pit is
extended up to the rock or any form of hard strata that is available.
If the case is that the soil cannot be considered as hard strata to a depth of 2 to 3m, the investigation
has to be extended. This extended depth has to be taken below the proposed bottom level of the
structure in the case of box or pipe culverts.
The soil investigation is adequate if the soil obtained is uniform and not soft. Mostly, the practice is
to conduct the investigation up to a depth that is equal to one and half the width of the proposed
foundation. This depth is taken below the proposed foundation. The normal auguring method is
mainly employed for this.
33. Confronting soft soils will call for the different type of structure and foundation. This will make it
necessary to ascertain the type of soil at various depths with the use of trial bore holes.
In some situations, the drilling of bore hole will result in the collapse of the surrounding soil. These
happen due to the soft texture of the soil material. Here the bore hole will not stand supported.
34. During such situations, a casing pipe is driven into the ground for some depth and later the hand
auguring is carried out.
For investigation depth greater than 5m or in the case of pile or shallow foundation, the method of
wash boring by using a casing pipe will be employed.
In the case of culverts and minor bridges, there is only the need for a qualitative idea of the various
soil layers. If there is no rock present, the representative samples are taken. These are obtained from
the borings at 1 to 1.5m intervals. This interval decision depends on the continuity of the soil type
or a change in the type of soil.
The table-1 shows the safe load for the foundation that is proposed for culverts and bridges.
The final design of the foundation involves the design of piles or well that will be based on the
properties of the soil that are determined from laboratory tests. These tests are conducted on the
undisturbed soil which is collectedat intervals.
35. Hydraulic Parameters in Investigation for Construction of
Bridges and Culvert
Proper inquiry with the residents who were residing in the proposed location for long is carried out
to understand the condition of flooding and the highest possible flooding levels.
These are verified with the help of any tell-tale marks that will be available in the nearby building,
trees, banks of stream etc. A suitable margin should be provided even if there is no doubt on the
collecteddata.
For already defined channels, the following is considered:
For 300m upstream and 150m downstream, a longitudinal section of the channel is taken
Minimum three cross sections, one over the alignment, the second one 150m upstream and
downstream must take.
The HFL (Highest Known Flood Levels) are marked on each of the cross sectiontaken. The
rugosity coefficient is judged based on the type of bed and the bank material.
The rugosity coefficient will hence enable the calculation of the velocity of flow. The various
method that is available is employed to determine the design flood discharge.
These details will provides the waterway required for the bridge and the arrangement of the span.
38. CONCLUSSION
This training helped me togain knowledge by experiencing various works
taking place int the site. By this inplant training I had a opportunity to
witness various situations inthe site andpractically andinnovatively
overcoming themin brief I learned about various new construction
technologies andmore importantly I experiencedthe whole constructionof
laying out a span of a girder bridge. This helped me inclearing various
theoretical andpractical doubts andmade me somewhatrealizethefuture
scopeof civilengineering