KONSTRUKSI BANGUNAN SIPIL Slab dan Girde

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KBS

BY:

DEASY MONICA P 131111003 YEDIE CHAHYADIE 131111028 KG-3A

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KBS || Girder and Slab at Fly Over

Deasy Monica P | Yedie Chahyadie i

PREFACE

Thank to Almighty God who has given His bless to the writer for finishing the English paper assignment entitled “Gider and Slab at Fly Over”.

The writer also wish to express his deep and sincere gratitude for those who have guided in completing this paper. This paper contains about girder and slab at fly over. There are six point that we explain about girder and slab at fly over.

Our paper also can be used as the guidance for those who want to learn more about slab and girder at fly over. Hopefully, this paper can help the readers to expand their knowledge about fly over.

Bandung, March 25th, 2016

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Deasy Monica P | Yedie Chahyadie ii

TABLE OF FIGURES

Figures 2.1 The Golden Gate Bridge... 2

Figures 2.2 JJ Fly Over... 2

Figures 2.3 Girder and Beam... 3

Figures 2.4 I-Girder... 4

Figures 2.5 T-Beam... 4

Figures 2.6 Segmental concrete girder box form... 5

Figures 2.7 Rolled steel girder... 5

Figures 2.8 Anatomy of plate girder... 6

Figures 2.9 Surviving section of Chepstow Railway Bridge girder, now at Brunel University, Uxbridge... 6

Figures 2.10 Brunel's bridges over the entrance locks to theCumberland Basin, Bristol Harbour... 7

Figures 2.11 Solid slab... 7

Figures 2.12 Void slab... 7

Figures 3.1 Corrosion at concrete reinforcement... 11

Figures 3.2 Crack at girder... 12

Figures 3.3 Tay Rail Bridge... 13

Figures 3.4 Inverythan Rail bridge... 13

Figures 3.5 Seong su bridge... 14

Figures 3.6 The car... 14

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Deasy Monica P | Yedie Chahyadie 1

CHAPTER I

INTRODUCTION

1.1 Issue Background

Transportation is one of our most basic human needs. Transportation is the act of moving something from one place to another. If we do not have a mode of transportation we will not be able to go to our job or to social functions as much as we want.

To move from one place to another, we can use land-transportation, air-transportation or water-air-transportation. For land-air-transportation, we can use road or railway for connection. For air-transportation we can use plane for connection. For water-transportation, we can use sailorship.

Fly over is one of alternative way for land-transportation which is the different construction from usual road. Fly over can passing the road or passing the river. Fly over itself has many kind of construction, like girder, pylon, abutment, slab and etc. This kind of construction can determine the strengthness of fly over. So, the choosing good material and design is a must for making fly over.

Slab and girder is one of construction that have to well-designed. Because the slab and girder is one of construction which is directly used by user. It based on the srength and comfort.

The problem that explained above made the writers interested to analize about construction of slab and girder at fly over. It based on choosing material, kind of the construction and etc.

1.2 Problem Identification

 What the definition about fly over, slab and girder.

 What is basic guide to choose the structure.

 What kind of classification about slab and girder for fly over.

 What the Advantages and Disadvantages with using slab and girder for fly over.

 What kind of issues or problems that always happen at slab and girder for fly over.

1.3 Objectives of This Write

 To know the definition about fly over, slab and girder.

 To know the basic guide to choose the structure.

 To know kind of classification about slab and girder for fly over.

 To know the Advantages and Disadvantages with using slab and girder for fly over.

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Fly over is a structure which joints two or more points which are separated by an accessible route/s or a man made structure to cut the traffic for faster mode of travelling. Reason behind going for a flyover is the traffic on the road goes on increasing and it’s don’t have any space left in both the dimensions, then the only option left will be to go to the third dimension and that is done through flyover construction.

The differences between fly over and bridge are:

Bridge Fly Over the width of the valley or river.

They are usually made over road flying over a traffic zone.

Bridges are usually built for trains, buses and cars.

They are usually built for road vehicles.

Figure 2.1 The Golden Gate Bridge

Source: http://bit.ly/1R9k2z6

Figure 2.2 JJ Fly Over

Source: http://bit.ly/1WbDa3U

 Slab

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Suspended slabsareslabsthat are not in direct contact with the ground. They form roofs or floors above ground level.Suspended slabsare grouped into two types: one wayslabswhich are supported on two sides.

 Girder

Agirderis a support beam used in construction. It is the main horizontal support of a structure which supports smaller beams.Girdersoften have an I-beam cross section composed of two load-bearing flanges separated by a stabilizing web, but may also have a box shape, Z shape and other forms.

Figure 2.3 Girder and Beam

Source: http://bit.ly/1SCiseH

2.2 Basic guide to choose the structure  Based on the function

The function of fly over which is on the middle of city to avoid the traffic jam must be different with the function of fly over which is to connect one village to another village. It means, based on the function is important to choose what kind of structure that we need.

 Based on strength and stability

Load factor give the affect of choosing the structure. If the load factor more than the carrying capacity of slab, so the slab has posibillity to collapse, because it can’t resist with the load factor.

 Based on the economy

The availabilities of fees give the affect of choosing the structure. If we don’t have much money, we can push the fees from choosing shape or structure.

 Based on the implementation

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2.3Types of Girder

a. Types of Girder Based on The Shape

o _{I-Girder Bridge}

This girder can made of composite material or non-composite material. For choosing kind of material, we have to consider strength or cost for this construction. An I-Girder is very simple to design and build and works very well in most cases, but more prone to torque/twisting forces. Box girders, being more stable are also able to span greater distances and are often used for longer spans, where I-beams would not be sufficiently strong or stable. However, the design and fabrication of box girders is more difficult than that of I beams.

Figure 2.4 I-Girder

Source: http://bit.ly/225EsRE

o _T-Beams

A reinforced-concrete bridge consisting of a floor slab monolithic with the supporting beams so that a cross section resembles a series of T beams. T-Beams is very economic for length 40-60 ft. But for tilt bridge structure, designing T-Beam need more complicated way. The comparison between length and width at T-Beam is recommended about 0.07 for simple T-Beams and 0.065 for continous T-Beams

Figure 2.5 T-Beam

Source: Ilmutekniksipil.com

o _{Box Girder}

A box girder or "tub girder" is, as the name suggests, a box shape. They consist of two vertical webs, short top flanges on top of each web, and a wide bottom flange connecting the webs together. A box girder is particularly resistant to torsion and, while expensive, are utilized in situations where a standard girder might succumb to torsion or toppling effects.

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 Rectangular steel box girder

 Trapezoidal steel box girder b. Concrete box girder

 Rectangular concrete box girder

 Trapezoidal concrete box girder

Figure 2.6 Segmental concrete box girder forms

Source: http://bit.ly/1R9pAcU

b. Another Types of Girder

o _{Rolled Steel Girder}

Arolled steel girderis a girder that has been fabricated by rolling a blank cylinder of steel through a series of dies to create the desired shape. These create standardizedI-beamand wide flange beamshapes up to 100 feet in length.

Figure 2.7 Rolled Steel Girder

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o _{Plate Girder}

Figure 2.8 Anatomy of Plate Girder

Source: http://bit.ly/1R9bVcd

A plate girder is a girder that has been fabricated by welding plates together to create the desired shape. The fabricator receives large plates of steel in the desired thickness, then cuts the flanges and web from the plate in the desired length and shape. Plate girders can have a greater height than rolled steel girders and are not limited to standardized shapes. The ability to customize a girder to the exact load conditions allows the bridge design to be more efficient. Plate girder can be used for spans between 10 metres and more than 100 metres (33 feet to more than 330 feet). Stiffeners are occasionally welded between the compression flange and the web to increase the strength of the girder.

o _{Ballon Flange Girder}

Figure 2.9 Surviving section ofChepstow Railway Bridgegirder, now atBrunel University,Uxbridge

Source: http://bit.ly/1UfwPHs

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Figure 2.10 Brunel's bridges over the entrance locks to theCumberland Basin,Bristol Harbour.

Source: http://bit.ly/1R9oVbp

c. Types of Girder Based on Construction method

o _{Cast in Situ}

Cast in situ is one of conventional method. Because, the making of concrete is in the location of slab construction.

o _Precast

Precast is one of slab construction method with fabrication in factory. Standard beam can be pre or post tension.

2.4Types of Slab

a. Based on forms.

 Solid Slab

Solid slab is the most simple thing of slab. Usually solid slab using the concrete reinforcement conventional.

Figure 2.11 Solid Slab

Source: http://bit.ly/1Wqqm9T

 Void Slab

Void slab is modification from solid slab. The function is for to reduce the load which isn’t be required near the neutral axis when the deflection happen

Figure 2.12 void Slab

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b. Based on structures.

 Corrugated, usually where the concrete is poured into a corrugated steel tray. This improves strength and prevents the slab from bending under its own weight. The corrugations run across the short dimension, from side to side.

 A ribbed slab, giving considerable extra strength on one direction.

 A waffle slab, giving added strength in both directions and it looks hollow from bottom.

c. Based on length and width.

 A one-way slab needs movement resisting reinforcement only in its short-direction because the movement along long axes is so small that it can be neglected. When the ratio of the length of long direction to short direction of a slab is greater than 2 it can be considered as a one way slab.

Long direction = ly Short direction = lx One way slab IF ly/lx > 2

 A two-way slab needs movement resisting reinforcement in both directions. If the ratio of the lengths of long and short side is less than two then movement in both direction should be considered in design.

Two way slab IF ly/lx < 2

d. Based on construction.

 Cast in Situ

Cast in situ is one of conventional method. Because, the making of concrete is in the location of slab construction.

 Precast

Precast is one of slab construction method with fabrication in factory. So, if the slab fabrication in factory is done, slab taken on the location of construction afterthat the slab is directly errected.

2.5 Advantages and Disadvantages using girder

o _I-Girder

Advantages Disadvantages

Cheap Limited in length (lateral torsional

buckling)

Simple to errect Less efficient

o _{Plate Girder}

Designer has greater freedom to vary the section to correspond with changes in the applied forces.

Compared with trusses they are

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Plate girders are aesthetically more pleasing than trusses and are easier to transport and erect than box girders.

The provision of openings for services is also more difﬁcult. The low torsional stiffness of plate girders makes them difﬁcult to use in bridges having small plan radius.

Plate girders can sometimes pose problems during erection because of concern for the stability of compression ﬂanges.

o Box Girder

The very large Torsional rigidity Difficult to cast in-situ due to the inaccessibility of the bottom slab and the need to extract the internal shutter Interiors of box girder bridges can be

used to accommodate service such as gas pipes, water mains etc.

For large spans, bottom flange could be used as another deck accommodates traffic also.

The maintenance of box girder is easier in interior space is directly accessible without use of scaffolding. It has high structural efficiency which minimizes the prestessing force required to resist a given bending moment, and its great Torsional strength with the capacity this gives to re-centre eccentric live loads,

minimizing the prestress required to carry them.

2.6 Advantages and Disadvantages using slab

 Based on the forms

o _{Solid slab}

Easy to construct with solid slab. Because of with conventional method

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The function is for to reduce the load which isn’t be required near the neutral axis when the deflection happen

o _{Void slab}

The load of building itself can be reduce

Usually void slab is one of precast method and using precast is not suggested for high rise building. Because it’s not good when there is earthquake

 Based on the length and width

o _{A One Way Slab}

It’s suitable for a long span It’s not effective if used in short span

o _{A Two Way Slab}

It’s suitable for short span It’s not too effective if used in long span

 Based on the construction

o _Precast

The duration of construction is efficient

Need big invesment

It’s not depend on the wheater The controlling of material isn’t optimum

It’s very efficient in terms of economy if the building is big scale

o _{Cast in situ}

The fees of making the concrete can be pushed

The making of the concrete depen on wheater

The connection each segmen can more homogen

Have to made the framework within the duration of working

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CHAPTER III

DISCUSSION PROBLEM

3.1 Case 1. Corrosion at concrete reinforcement

Figure 3.1 Corrosion at concrete reinforcement

Source: http://1.usa.gov/1XweVxL

 Cause

The corrosion was caused by Carbonation from the air, Chlorides from sea water, Magnesium salts, Sulphate attacks from sea water and etc.

 Impact

1. The structure slowly but surely become crack. 2. The capability of load resistance is decreasing.

3. The cost will be higher for paying the maintenance service. 4. Dangerous for safety bridge’s user

 Prevention

1. Do a protection for reinforcment that we use. Like if we see the redness at reinforcement, we can clean the surface. Afterthat, we paint the surface of reinforcement.

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3.2 Case 2. Crack at Girder

Figure 3.2 Crack at girder

Source: http://1.usa.gov/1XweVxL

 Cause

There are factors that caused crack at girder before the construction 1. Temperature.

2. Corrosion at reinforcement. 3. Bad construction method. 4. Using bad material.

5. Arrange the reinforcement with not properly.

There are factors that caused crack at girder after the construction 1. Wheather.

2. Load.

 Impact

The strengthness of girder will be dicreasing and solwy but surely it will be dangerous for the structure and bridge’s user.

 Prevention

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3.3 Case 3. Girder failure.

1. Tay Rail bridge

Figure 3.3 Tay Rail bridge

Source: http://bit.ly/1XwfcAV

Location : Dundee

Country : Scotland

Date : 28 December 1879

Construction type : Continous girder bride, wrought iron framework on cast iron

columns, rail way.

Reason : Faulty design, construction and maintenance, structural

deterioration and wind load.

Casualities : 75 killed and no survivors.

Damage : Bridge unusable, girders partly reused and train damaged.

2. Inverythan Rail Bridge

Figure 3.4 Inverythan Rail bridge

Source: http://bit.ly/1WrTeyC

Location : Aberdeenshire

Country : Scotland

Date : 27 November 1882

Construction type : Cast iron girder rail

Reason : Hidden defects in cast iron caused collapse as train passed

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Casualities : 5 killed, 17 injured

Damage : Bridge rebuilt

3.4 Case 4. Slab failure and case

1. Seong su bridge

Figure 3.5 Seong su bridge

Source: http://bit.ly/1XwhWhs

Location : Seoul

Country : South Korea

Date : 21 October 1994

Construction type : Cantilever bridge crossing Han River

Reason : Structural failure was caused by improper welding of the

steel

Trusses of the suspension structure beneath the concrete slab

Roadway.

Casualities : 32 killed, 17 injured

Damage : 48-metre slab between the fifth and the sixth pier collapsed

2. Couple cheats death after flyover slab falls on car

Figure 3.6 The car

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Location : Delhi

Country : India

Date : 15 Februari 2015

Reason : The concrete slab reportedly loosened from the crane hoist

while the labourers were trying to install it

Casualities : A husband and wife and a labourer were death

Damage : 48-metre slab between the fifth and the sixth pier collapsed

3. Bridge and slab failure after earthquake

Figure 3.7 Bridge and slab failure

Source: http://bit.ly/1PcZ1lP

Location : Wenchuan

Country : China

Date : 12 May 2008

Reason : Earthquake with 7.9 magnitude

Casualities : Killed 69.197 people and left 18.222 missing because of

earthquake

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CHAPTER IV

FINAL

4.1 Conclusion

From the explaining above, we can conclude that

1. Basic guide to choose the structure are based on the function, strength and stability, economy and implementation.

2. Types of girder are I-Girder, T-Beams and box girder. On the other hand, there are another types of girder, like rolled steel girder, plate girder and ballon flange girder. 3. Types of slab are based on forms, structures, length and width and constructions.

4.2 Suggestion

1. For slab, We have to choose kind of slab wisely. Because so many types of slab based on forms, structures, length and width and constructions. We have to choose the structure based on the function, strength and stability, economy and implementation.

2. For girder, if you need for short span, you can use I-Girder. If you need for long span and easy for errection, you can use plate girder. If you need for long span, high torsional and easy to maintenance, you can use box girder. Last but not least,choose the structure it’s still based on the function, strength and stability, economy and implementation for itself.