A Report On Integral Abutment Bridge

Dissertation Project 1 Mid-Review M.Tech. Sem. III (Structural Engineering)

A study on Integral Abutment Bridge.

Report Prepared By

Sanket D Panchal (IU1651180009)

Department of Civil Engineering Indus Institute of Technology & Engineering INDUS UNIVERSITY Ahmedabad 382115 October 2017

INTEGRAL ABUTMENT BRIDGE

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Comprehensive Report on Mid-review of DP 1 Submitted in partial fulfillment of the requirements

For the degree of Master of Structural Engineering

By: Sanket D Panchal (IU1651180009) Internal Guide: Prof. Tejas Rathi

Department of Civil Engineering Indus Institute of Technology & Engineering INDUS UNIVERSITY Ahmedabad 382115 October 2017

INTEGRAL ABUTMENT BRIDGE

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CERTIFICATE

This is to certify that the Comprehensive Report on the Seminar, carried out on A Study of Integrak Abutment Bridge., submitted by Sanket Panchal (IU1651180009), towards the partial fulfillment of the requirements for the degree of Master of Technology in Structural Engineering of Indus University, Ahmedabad, is the record of work carried out by him under my supervision and guidance during July 2017 to October, 2017. In my opinion, the submitted work has reached a level required for being accepted for mid-review.

Prof. Tejas Rathi

Prof. Tejendra Tank

Faculty Guide,

Head of Department

(Designation)

(Civil Engineering)

Department of Civil Engineering,

IITE,

IITE,

INDUS UNIVERSITY,

INDUS UNIVERSITY,

AHMEDABAD

AHMEDABAD

INTEGRAL ABUTMENT BRIDGE

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INDEX Sr. No 1

2

3

Topic

Page No

Introduction

6

1.1.

General

7

1.2.

Bearing type bridges

7

1.3.

Shortcomings of bearing bridges

8

1.4.

Introduction to integral bridges

11

1.5.

Advantages of integral bridges

12

1.6.

Need of study

12

1.7.

Objective of study

13

1.8.

Scope of work

13

Integral Bridge Concept

14

2.1.

Definition and Concept

15

2.2.

Planning Consideration

15

2.3.

Design Difference

18

2.4.

Seismic Design Consideration

19

2.5.

Code Provision

19

2.6.

Limitation Of Concept

19

Literature Review

21

3.1.

22

Research Paper 1

INTEGRAL ABUTMENT BRIDGE

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3.2.

Research Paper 2

24

3.3.

Research Paper 3

26

3.4.

Research Paper 4

28

3.5.

Research Paper 5

30

3.6.

Research Paper 6

32

3.7.

Research Paper 7

34

3.8.

Research Paper 8

36

3.9.

Research Paper 9

39

3.10. Research Paper 10

INTEGRAL ABUTMENT BRIDGE

41

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Chapter 1 INTRODUCTION

1.1. GENERAL 1.2. BEARING TYPE BRIDGES 1.3. SHORTCOMINGS OF BEARING BRIDGES 1.4. INTRODUCTION TO INTEGRAL BRIDGES 1.5. ADVANTAGES OF INTEGRAL BRIDGES 1.6. NEED OF STUDY 1.7. OBJECTIVE OF STUDY 1.8. SCOPE OF WORK

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1.1. GENERAL. For many centuries bridges were built without expansion joint and bearing. But in 20

th

century

as the engineering and analysis became more sophisticated there has been the inclusion of joints and bearings in the design of bridges. In the current practice of bridge construction there has been the inclusion of the joints, to decrease the span of the bridge, and bearing, to transfer the load of superstructure to the substructure. We refer this sort of bridges as “Bearing Bridges”. Here the fore-mentioned inclusion has drawbacks from both aesthetical and functional point of view. The distress caused by these elements viz. joints and bearings, is the major cause of concern noticed in the bridges constructed over last fifty years. Despite of having the above mentioned drawbacks/weak-links bearing bridges are popular in India due to ease in their design and construction. On the other hand, “Integral Bridges” are the bridges without any joint and bearings. This eliminates the causes of distress that were observed in bearing type bridges. This results in the improvement of the bridges both aesthetically and functionally.

The further introduction on both type of bridges is briefed in this chapter. Also this chapter will deal with the need of study, scope of the study as well as the objective for which the study is carried out.

1.2. BEARING TYPE BRIDGE As specified earlier the expansion joints and bearing are considered to be the weak links of bearing bridges. However, they are provided with certain purpose.

Expansion joint are provided to serve the purpose of accommodation of the thermal and volume change movements without allowing leakage of water through it. However, the failure of expansion joints results in the water leakage to bearings and structure. This damages both, structure and bearings. Also, once the bearings are damaged are difficult to replace or repair. Repair and replacement of bearings involves costs and time.

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The typical bearing bridge and its components are shown in the figure below.

Fig 1.2.1 Bearing Bridge and its components Thus elimination of both these components proves beneficial as they represent weak links of bridges and also renders fragility. Despite of having this issues, their ease in design and construction has been the reason of their popularity. Answer to this issues is the introduction of INTEGRAL BRIDGES.

1.3. SHORTCOMINGS OF BEARING BRIDGE Need for joint less bridge arises because of certain shortcomings of bearing bridges. These shortcomings are listed below: o Bearings and expansion joints proves expensive matter to install, maintain, repair and replace. o Installation of bearings and joints is an increased activity and hence its time consuming too. o The run-off water leakage through expansion joints causes corrosion problems at the girder ends, bearings and further to substructure system. o The failure of joints reduces the riding quality. Elastomeric bearing can split or rupture due to unanticipated movements, or can ratchet out of position. o Malfunctioning of bearings may lead to unanticipated structural failure.

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Life cycle of bearing is less compared to the life cycle of bridges, hence there are recurrent costs to maintain bearings. During earthquakes or any other accidental load, there is possibility of dislodgement of the span.

Short comings of bearing bridges can be shown below in terms of the pictures of failures occurred in bearing bridges during any accidental load

Fig 1.3.1 Failure of metallic bearing Surajbari Bridge (old) Kutch

Fig 1.3.2 Transverse movement of deck in surajbari bridge (New) in Kutch INTEGRAL ABUTMENT BRIDGE

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Fig 1.3.1 Expansion joint damaged due to excessive movement of Surajbari Bridge (new) in Kutch

Fig 1.3.4 Padshahi Bagh (J.K.) damaged pier cap, bearing, and superstructure

Fig 1.3.5 Displacement of Elastomeric Bearing in Darfield (NZ) during Earthquake INTEGRAL ABUTMENT BRIDGE

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1.4. INTRODUCTION OF BEARING BRIDGE Integral bridges are defined as The bridges without expansion joints and bearings The bridges with integral abutments Integral abutment is the abutment that is constructed and joined with the deck without any expansion joint. Integral bridge construction includes the monolithic construction between the deck and the substructures. They are generally designed in a way that all the supports equally negotiates the thermal and braking loads.

Fig 1.4.1 Integral Abutment Bridge Components

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1.5. ADVANTAGES OF INTEGRAL BRIDGES / WHY GO FOR INTEGRAL BRIDGES? Advantages of integral bridge over conventional bridges are as follows: As the joints and bearings installation has been eliminated, the time is thus reduced and hence speed in construction is achieved. The maintenance cost of bearings and joints contributed to the more maintenance cost in bearing bridges compared to integral bridges. Construction of joint less bridges improves the riding quality and reduces vehicular impact loads.

Elimination weak links (bearings and joints) prevents the dislodgement of span due to accidental load. Due to elimination of expansion joint the future widening is simplified in integral bridges.

Other benefits are: Simple beam seats. Added redundancy and capacity for catastrophic events. Improve Load distribution. Enhance protection for weathering steel girders.

1.6. NEED OF STUDY In India, limited data is available to study the comparison between integral and bearing bridge systems, hence it restricts the probability of adopting a particular system in certain condition. The suitability of Integral Bridges in Indian condition from functional and economical point of view is required to be assessed. This forms the need to carry out the comparative study between bearing and integral bridge systems. INTEGRAL ABUTMENT BRIDGE

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1.7. OBJECTIVE OF STUDY Studying the behavior of Integral Bridges and Bearing Bridges under temperature. Understanding the effect of braking and temperature forces on abutment and earth pressure calculation on it. Analysis of integral and bearing bridges with different parameters.

1.8. SCOPE OF STUDY Literature review Understanding earth pressure calculation for different type of load cases. Modelling of bearing & integral bridges for 3, 4 & 5 nos. of span using STAAD pro. Bridge parameters for study Two lane Carriageway.

3, 4 & 5 nos. span Skew angle 0 to 60 at 10 degree intervals.

Comparative

study

displacement

and

parameters moments,

Forces,

Behavioral

difference with the number of span, Live load, Thermal Stress, Soil Parameters Density of soil – 18 KN/m

3

Angle of internal friction - 20⁰

2

Safe bearing capacity – 300 KN/m (rocky strata).

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Chapter 2 INTEGRAL BRIDGE CONCEPT

2.1. DEFINATION AND CONCEPT 2.2. PLANNING CONSIDREATION 2.3. DESIGN DIFFERENCE 2.4. SIESMIC DESIGN CONSIDRATION 2.5. CODE PROVISION 2.6. LIMITATION OF CONCEPT

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2.1. DEFINATION AND CONCEPT Integral bridge is generally defined as the bridge with integral abutments. Sometimes, the definition is given as, the bridge with no joints for movement and no bearings. Integral bridges are based on the concept that the stresses due to temperature effect and movements are transferred to the substructure by the rigid connection between substructure and superstructure. The flexibility of the substructure in transfer of loads is considered to be the point of concentration in the integral bridge concept.

2.2. PLANNING CONSIDREATION The aspects to be considered while planning are as follows: Length of the Structure Climatic Condition Seismic Zone Type of Superstructure Type of Abutments Type of Foundations And Sub-Soil Conditions Geometry of the Structure Complexity in Analysis and Design These points are explained in brief below:

2.2.1 LENGTH OF STRUCTURE The length of the structure depends upon the climatic condition, range of temperature variation both seasonal and daily, material of the structure, geometry of the structure, sub soil conditions and pier height. Due to in appropriate experimental study the length of the structure is limited up to 150m till further research work is carried out.

2.2.2 CLIMATE CONDITION INTEGRAL ABUTMENT BRIDGE

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The integral bridges are sensitive to daily and seasonal temperature and moisture change. Lesser the variation lesser are the induced stresses in the bridges. Thus integral concept is more suitable in the regions with lesser variation in temperatures. According to the IRC 6:2000 the southern and eastern regions of our country are suitable for such concept.

2.2.3. SEISMIC ZONE: The added degrees of redundancy in the structure helps in minimizing the risk of failure of the structure. Hence integral bridge concept in suitable in the high seismic zone (zone IV & V).

2.2.4. TYPE OF SUPERSTRUCTURES: Type of superstructure also have significant influence on the design of integral bridges. The following are the superstructures that are usually adopted: Cast in situ RC slab/voided deck slab. Precast RC girders with composite deck slab. Steel girders with concrete composite deck. Pre-cast pre-stressed girders with in situ composite deck.

2.2.5. TYPE OF ABUTMENT: Following are the types of abutment used in the concept of integral bridges. (a) (b) (c) (d) (e) (f)

Frame Abutment Frame Abutment Bank Pad Abutment Bank Pad Abutment End Screen Abutment End Screen Abutment

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Fig 2.2.1 Types of integral abutment

2.2.6. TYPE OF FOUNDATION AND SUB-SOIL CONDITION: Sub soil condition is an importance consideration while choosing the type of foundation and for ascertaining the feasibility of integral structures. The primary criterion is the need to support the piers and abutments on relatively flexible foundation. It is desirable to have flexible foundation to accommodate for the structural movement under thermal loading to dissipate thermal stresses. In case the hard strata is met, then the site is not suitable for integral bridges. Also at the sites where soil is liable to liquefaction, slip failure, boiling, the adoption of integral bridge in not suitable.

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2.2.7. GEOMETRY OF THE STRUCTURE: Basically for integral bridges, simple geometry has been considered easy approach for designing. Structures, where there are abrupt changes in the mass, stiffness or geometry along the span should be avoided. Also, it is preferable that the span are symmetrically placed and the adjacent pier stiffness doesn’t differ substantially. Tall piers and high abutments are suitable for integral bridges (frame section). Height of abutments on either side must be same or else it will cause unbalanced lateral loads resulting in side sway.

2.3. DESIGN DIFFERENCE The basic and main difference in design of bearing and integral type bridge is the treatment of thermal movements. For and integral bridge, the flexibility of pier and relative stiffness of deck, abutments and piers, also the movement of abutment while evaluating forces is important to undertake. The integral bridges are designed with their stiffness and flexibility distributed throughout the soil/structure system without any hard/soft spots. This is unlike to the design of bearing bridges where fixed piers are considered for taking care of all the lateral loads in specified direction. The abutments and piers are considered flexible for negotiating thermal movements, on the other hand, they are considered stiff to accommodate for the lateral forces, soil pressures and braking forces.

2.4. SEISMIC DESIGN CONSIDERATIONS: Seismic behavior of integral bridges are discussed below: INTEGRAL ABUTMENT BRIDGE

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2.4.1. INTEGRAL BRIDGE FOR HIGHER SEISMIC ZONES: Integral bridges perform better during an earthquake due to the fixity and restraints at the connections with piers and abutments. The ability of integral piers and abutments to accommodate large superstructure movements during earthquake results in improved seismic performance as compared to the bearing bridges. When the integral abutment moves under seismic loads the passive earth pressure is generated which dissipates significant amount of energy. Abutment should be designed to resist passive earth pressure being mobilized by the backfill on one side, which should be greater than maximum estimated longitudinal earthquake force transferred to the abutment.

2.4.2. INTEGRAL BRIDGES FOR LOW SEISMIC ZONES: The seismic displacements are dependent on the period of the structure and spectral acceleration. The seismic displacements are much higher in regions of high seismicity as compared to the displacement demands for service loads and thermal movements. Bridges with long span, tall or slender piers, massive superstructure and foundation flexibility have longer periods and thus large displacements. Thus long period bridges with integral abutments lead to large seismic displacements while short period bridges with integral abutments lead to smaller seismic displacements. Hence it is recommended to use integral bridges in low seismic regions.

2.5. CODE PROVISIONS: For integral bridge design, the “British Note” BA42/96 gives the following clauses:

2.5.1. LONGITUDINAL MOVEMENT: The longitudinal movement of integral abutment should be limited to +20mm (nominal, 120 year return period) from the position of time of restraint during construction.

2.5.2. THERMAL EFFECT: The bridge spans and abutments are joined during construction at a temperature within +10 ⁰C of the mean between extreme minimum and maximum shade air temperatures. INTEGRAL ABUTMENT BRIDGE

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2.5.3. EARTH PRESSURE FOR ABUTMENTS: The height of the abutments means that the magnitude of passive pressure acting on the back of the wall. The design of abutment should ensure that the structure is strong enough to resist lateral pressures that could build up behind the wall, and yet flexible to accommodate movement.

2.5.4. EARTH PRESSURE DISTRIBUTION: A uniform value of K* over the top half of the retained height of the wall, with lateral earth pressure then remaining constant with depth as K* drops towards K0. If the lateral earth pressure falls to K0 then below that depth pressure are according to the in situ value of K0.

Fig. Pressure distribution for frame abutment.

Chapter 3 INTEGRAL ABUTMENT BRIDGE

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LITERATURE REVIEW 3.1.

STUDY OF MECHANICALLY STABILIZED EARTH STRUCTURE SUPPORTING INTEGRAL BRIDGE ABUTMENT

3.2.

SOIL STRUCTURE INTERACTION ANALYSIS FOR INTEGRAL ABUTMENT BRIDGE SYSTEM

3.3.

SEISMIC ANALYSIS OF INTEGRAL ABUTMENT BRIDGES CONSIDERING SOIL-STRUCTURE INTERACTION

3.4.

ANALYSIS OF INTEGRAL BRIDGE BY FINITE ELMENT METHOD

3.5.

COMPARATIVE STUDY OF BEHAVIOR OF INTEGRAL AND BEARING TYPE BRIDGE UNDER TEMPERATURE LOADING

3.6.

BEHVIOR OF INTEGRAL ABUTMENT BRIDGE

3.7.

COMPARATIVE STUDY OF BEARING AND INTEGRAL TYPE BRIDGES AS PER INDIAN STARNDARDS

3.8.

BEHAVIOR OF INTEGRAL ABUTMENT BRIDGE BY DIFFERENT END CONDITIONS

3.9.

A COMPARATIVE STUDY OF CONVENTIONAL RC GIRDER BRIDGE AND INTEGRAL BRIDGE

3.10.

BEHAVIOR OF INTEGRAL ABUTMENT BRIDGE WITH SPRING ANALYSIS

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3.1.

STUDY OF STRUCTURE ABUTMENT

Title Journal Name Year Publishing Sr. No. A

MECHANICALLY STABILIZED EARTH SUPPORTING INTEGRAL BRIDGE

Study of Mechanically Stabilized Earth Structure Supporting Integral Bridge Abutment ASCE of DEC 2016

Details Objective of study





B

Need of study



C

Parameters considered



D

Type of analysis/design adopted

E

If analysis, then Modelling method



F

Carried out in which software (for analysis)



INTEGRAL ABUTMENT BRIDGE

This paper will present the effects of the loading from an integral bridge abutment on a Mechanically Stabilized Earth (MSE) retaining wall structure. The results of the two models will be compared to an empirical design methodology as developed based upon American Association of State Highway and Transportation Officials (AASHTO) design guidelines To understand the effects of thermal deformation phenomenon (contraction and expansion) of the bridge deck on an MSE wall structure and more particularly the induced tensile force in soil reinforcements and lateral displacement at the front face of the wall as a result of the bridge movement. The analysed section of MSE wall is approximately 6.5m tall, with 7.0m (50mm x 4mm) long discrete, high adherence metallic reinforcing strips, supporting a 92m wide x 18.48m long single span bridge.

A geotechnical numerical finite difference program, FLAC v5.0 2D, were utilized to model a standard abutment (true bridge abutment on bearings) and an integral bridge abutment A geotechnical numerical finite difference program, FLAC v5.0 2D, were utilized to Page 22

G

Conclusions





INTEGRAL ABUTMENT BRIDGE

model a standard abutment (true bridge abutment on bearings) and an integral bridge abutment Advances in bridge structures supported by MSE walls has made the use of numerical modelling as a tool for design verification of internal stability of MSE walls against standard AASHTO design methods very beneficial, since the affects to the retaining walls due to the global behaviour of integral abutments are more complex than traditional abutments. Variations to the internal elements of MSE walls with different bridge structures shown in this report have increased the need for design coordination between the structural and geotechnical elements.

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3.2.

SOIL STRUCTURE INTERACTION ANALYSIS FOR INTEGRAL ABUTMENT BRIDGE SYSTEM

Title

SOIL STRUCTURE INTERACTION ANALYSIS FOR INTEGRAL ABUTMENT BRIDGE SYSTEM Indian Geotechnical Conference of 2014

Journal Name Year Publishing Sr. No. A

Details Objective of study





B

Need of study

 

C

Parameters considered

      





INTEGRAL ABUTMENT BRIDGE

The main objective of this study to observe the trends in bending moment, deflection in longitudinal girders and in piles subjected to the given dynamic loading. The parametric study including different soil types, different type of connections between pile and abutment, effect of water table, different earthquake loading is carried out and the results are compared for both the conditions including SSI and without SSI. One of the two major problems observed with IABs is the development of lateral earth pressures against the abutments. The other is the void development under approach slab. Effective span 36 Width 10.36 Deck slab thickness 0.226 Pile length 15 (HP- 10 x 125) Abutment (d x t) 5 x 1.2 Girder AASHTO guidelines To capture the real time scenario of soil the heterogeneity soil is considered including the four horizontal stratified zones including medium dense (SAND 1), dense (SAND 2), medium stiff(CLAY 1) and stiff (CLAY 2). SAND 1, 2.4 m SAND 2, 2.4 m CLAY 1, 4.8 m CLAY 2, 4.8 m with 5m of overburden. Details of parametric study Various cases considers for analysis: o Case 1 Page 24

D E F

G

Type of analysis/design adopted If analysis, then Modelling method Carried out in which software (for analysis)



SAND1,SAND2,CLAY1,CLAY2 o Case SAND2,SAND1,CLAY1,CLAY2 o Case CLAY1,SAND1,SAND2,CLAY2 o Case CLAY2,SAND1,SAND2,CLAY1 Dynamic analysis is carried out.



Finite element modeling.



Conclusions

 o

In this research paper 3-Dimensional model of a prestressed concrete bridge is developed using finite element software MIDAS CIVIL (V13) for both fixed and spring support. Displacements: In fixed base analysis for both pile and girder shows fewer displacements in all directions. In SSI analysis CASE 4 which includes shows considerably more displacements in Xdirection for both pile and girder that other cases and Y and Z direction displacements is found to be almost same. CASE 3 proves to be a good combination for least displacement. Rotation: Girder rotations against the dynamic loading are found to be negligibly small with comparison of the pile head rotation. It concludes that the IAB system with fixed connection between pile and abutment creates negligibly small rotational moment in the superstructure. Rotations observed to be more in all the cases which includes the soil structure interaction effect than compared to the fixed base analysis of the IAB system. Soil behavior: With the hysteresis obtained from the analysis which includes the soil structure interaction effect the shear stresses developed in all analysis cases are within the permissible range and among all cases of analysis CASE 3 shows the less shear stress.

o

o  o o

o

 

INTEGRAL ABUTMENT BRIDGE

2 3 4

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3.3.

SEISMIC ANALYSIS OF INTEGRAL ABUTMENT BRIDGES CONSIDERING SOIL-STRUCTURE INTERACTION

Title Journal Name Year Publishing Sr. No. A

SEISMIC ANALYSIS OF INTEGRAL ABUTMENT BRIDGES CONSIDERING SOIL-STRUCTURE INTERACTION ASCE of 2013

Details Objective of study



B

Need of study



C

Parameters considered

      

D E

Type of analysis/design adopted If analysis, then Modelling method

   

F

Carried out in which software (for analysis)

INTEGRAL ABUTMENT BRIDGE



This paper is focused on seismic analysis of integral abutment bridge considering soil structure interaction. Due to various limitations and poor performance of bearing type bridges it is now necessary to get rid out of typical expansion joints and bearings from bridges and now it’s a time to introduce something which can overcome this limitations and problems of typical bearing type bridges integral bridges are becoming popular nowadays . Length of bridge = 45.5 m No of traffic lanes = 2 Width of bridge = 32.19 m Skew angle = 15 degree This bridge comprises rcc deck which is supported on steel girder. The abutments are 3 m high and 0.9 m thick. The bridge was subjected to moving HS-20 design truck at a speed of 33.5 m/s. Finite element analysis was carried out The bridge deck was modelled using shell elements. The supporting beams were modelled using beam elements. The composite section between the bridge deck and the supporting girders was modelled using nonlinear link elements A three-dimensional finite element model of the bridge superstructure and substructure was modelled using the finite element software SAP2000. Page 26

G

Future scope of work

INTEGRAL ABUTMENT BRIDGE



The results developed by our model compare very favourably with the data found in the referenced paper which indicates that our numerical model is accurate.

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3.4.

ANALYSIS OF INTEGRAL BRIDGE BY FINITE ELMENT METHOD

Title Journal Name Year Publishing Sr. No. A

Analysis of Integral Bridges by Finite Element Method ELSEVIER (The 2nd International Conference Rehabilitation and Maintenance in Civil Engineering) of

Details Objective of study



B

Need of study



C

Parameters considered

 

D E F G

on

Type of analysis/design adopted If analysis, then Modelling method Carried out in which software (for analysis) Conclusion

INTEGRAL ABUTMENT BRIDGE

   

In this study, a finite element analysis has been performed to gain insight into the interactions between integral abutments, approach fills, foundation piles and foundation soils. The finite element analyses indicate appreciable rotations occur in integral abutments, resulting in the shear and moment reductions in the piles To understand the influence of finite element analysis on the design of integral abutment bridge. A 300-ft long integral abutment bridge was selected for the parametric analyses. It was assumed that the bridge consists of W44x285 steel girders spaced 8 feet apart, with a 10-inch thick concrete deck, resting on 10-ft high 3.0-ft thick abutments, which are supported by HP10x42 steel piles, spaced 6 feet apart. Finite element analysis. ANYSYS software is used for modelling of bridge. ANYSYS software is used for modelling of bridge. This research project investigated the complex interactions that take place between the structural components of the integral bridge and the soil through analytical studies. A literature review was conducted to gain insight into the integral bridge/soil interactions, and to synthesize the information available about the cyclic loading damage to piles of integral bridges. Finite element analysis indicate that Page 28

the presence of the approach fill significantly reduces the stresses in piles supporting integral bridges. Pile stresses are slightly higher for the contraction mode than for the expansion mode.

INTEGRAL ABUTMENT BRIDGE

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3.5.

COMPARATIVE STUDY OF BEHAVIOR OF INTEGRAL AND BEARING TYPE BRIDGE UNDER TEMPERATURE LOADING

Title

Comparative Study of Behaviour of Integral and Bearing Type Bridge under Temperature Loading International Journal for Scientific Research & Development of March 2015

Journal Name Year Publishing Sr. No. A

Details Objective of study



B

Need of study



C

Parameters considered

    

D E F G

Type of analysis/design adopted If analysis, then Modelling method Carried out in which software (for analysis) CONCLUSIONS

INTEGRAL ABUTMENT BRIDGE



Description In this paper, results of comparative study of behaviour of integral and bearing type bridge under temperature loading is shown. As temperature changes daily and seasonally, the spans of integral bridge increase and decrease, pushing the abutment against the approach fill and pulling it away. As a result the bridge superstructure, abutment, approach fill, foundation piles and foundation soil are subjected to cyclic loading, and hence understanding their interactions is important for effective design and satisfactory performance of integral bridges Span length = 25 m No of lanes = 2 Spring Analysis As the paper is centred towards the behavior of integral bridges under temperature, the forces considered are only the temperature forces Temperature forces are calculated as per IRC: 6-2014. Calculation of temperature forces



Linear static analysis has been carried out for both the type of bridges under different loads. STAAD Pro software is used for analysis.



STAAD Pro software is used for analysis.



In bearing bridges, temperature induced moments are not found to be significant as the Page 30







INTEGRAL ABUTMENT BRIDGE

provision of expansion joints absorb all the stresses. Hence, compared to integral bridges bearing bridges will not have any moment in the superstructure due to temperature. In case of One Span Integral bridge there is a hogging moment throughout the span because of the expansion of the superstructure. Similarly, there will be sagging moment throughout the span in case of contraction. In case of Integral Bridges near the junction of deck slab and abutment stresses are observed, while in case of bearing bridges these stresses are found to be zero, this is because of the provision of expansion joints. Results also states that as the number of span increases the rate of increase in moment and displacement due to temperature reduces.

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3.6.

BEHVIOR OF INTEGRAL ABUTMENT BRIDGE

Title Journal Name Year Publishing Sr. No. A

Behaviour of Integral Abutment Bridge International journal of scientific progress and Research of February 2014

Details Objective of study

B

Need of study

C

Parameters considered

D

Type of analysis/design adopted

INTEGRAL ABUTMENT BRIDGE



a comparative study is carried out on a typical IAB and a simply supported bridge (SSB) of same geometry and loading conditions, and compares these bridges with spring and without spring analysis at both ends.  To understand and see Bending Moment and shear force at various locations and to see their patterns in integral bridge and bearing bridge.  The bridge under consideration is an RCC Fly Over (T-beam) bridge of 151.5 m total length between two abutments excluding the length of approach stabs on either side.  bridge is divided into seven equal spans; each span is 21.5 m effective length  10.55 m wide in cross section(Two Lane Bridge with footpath).  The bridge deck is 300 mm thick for inner panels.  Traffic load as per IRC Class AA single train or two trains of Class A (IRC-6-2000).  Portion of deck provide as a footpath is over hang for a clear length of 1.45 m on either side from the face of external girder rib.  Thickness of overhang portion of the deck is 300 mm at the face of external support which gradually reduces to 200 mm at free end.  A parapet wall or anti crash barrier is provided at the free end of the footpath of 200 mm thickness and 900 mm height while at the end of the overhang other side a median verge (divider) of 300 mm thickness and 240 mm depth is provided.  Bridges were analysed for this work by using Midas Civil Software Page 32

E F G

If analysis, then Modelling method Carried out in which software (for analysis) Future scope of work



Conclusions



 

 

INTEGRAL ABUTMENT BRIDGE

bridges were modelled for this work by using Midas Civil Software Midas Civil Software Now a day's Integral abutment bridge is becoming more popular due to its benefits like maintenance cost initial cost its life smooth riding etc, but much more research yet to be required regarding its length width and its moment and much more scope to design curve integral abutment bridges. Near the junction of deck slab and abutment IAB has lesser stresses than SSB, because of rigid connection between abutment and deck slab, there is transfer of stresses, but in case of IAB WSA (Integral Abutment Bridge With Spring Analysis) the stresses is more as compare to SSB and less as compare to IAB because at ends abutments a spring force is develop. Bending moment is more in SSB as compare to IAB and bending moment is less in IAB WSA as compare to both. Overall we can say that moment and shear stress developed in various components of IAB is higher than SSB, so it can be concluded that moments, stresses and forces developed in IAB is higher than the equivalent SSB because of monolithic connection between various components of the bridge, but if we provide spring analysis at both ends of the end abutment then the shear force, bending moment and forces will reduce as compare to IAB.

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3.7.

COMPARATIVE STUDY OF BEARING AND INTEGRAL TYPE BRIDGES AS PER INDIAN STARNDARDS

Title

Comparative Study of Bearing and Integral Type Bridges as Per Indian Standards International Journal of Science Technology & Engineering of May 2015

Journal Name Year Publishing Sr. No. A

Details Objective of study



B

Need of study



C

Parameters considered

   

In this paper, the design moments for the different components of superstructure are compared for both types of bridges. To understand behaviour and moment for both integral and bearing type bridge and to see the difference in area of reinforcement in deck slab, moment in girder, sagging moment in deck slab, hogging moment for one span two span and three span and for both integral bridge and bearing type bridge. One span two span and three span integral bridges are modelled. Span length – 25 m No of lanes – 2 Loads considered and calculated in accordance with the IRC: 6-2014 for analysis purpose

 D

Type of analysis/design adopted

E

If analysis, then Modelling method Carried out in which software (for analysis)



Conclusions



F

G





INTEGRAL ABUTMENT BRIDGE

Grillage analogy is used for modelling one span two span and three span bridges STAAD PRO software is used for modelling of one span two span and three span integral bridge. it can be concluded that as the number of span increases the rate of reduction in sagging moments also reduces in integral bridges compared to bearing bridges. In case of internal diaphragm, it can be said that, for this case the sagging moment is found to be almost similar in one span, two span and Page 34

three span integral bridges. However, hogging moment is found to be decreasing compared to bearing bridge diaphragm, with the increase in number of span.

INTEGRAL ABUTMENT BRIDGE

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3.8.

BEHAVIOR OF INTEGRAL ABUTMENT BRIDGE BY DIFFERENT END CONDITIONS

Title Journal Name Year Publishing Sr. No. A

B

Behaviour of Integral Abutment Bridge by Different End Conditions International Journal of Current Engineering and Technology of 2014

Details Objective of study



Need of study





C

Parameters considered



    

INTEGRAL ABUTMENT BRIDGE

The paper motive is to study the trends in bending moment, shear force and deflection in central and end girders and deck slab due to dead load, live load with combination of thermal loads. As temperature change daily and seasonally, the lengths of integral bridges increase and decrease, pushing the abutment against the approach fill and pulling it away. As a result the bridge superstructure, the abutment, the approach fill, the foundation piles and the foundation soil are all subjected to cyclic loading, and understanding their interactions is important for effective design and satisfactory performance of integral bridges. The bridge under consideration is an RCC Fly Over (T-beam) bridge of 151.5 m total length between two abutments excluding the length of approach stabs on either side. bridge is divided into seven equal spans; each span is 21.5 m effective length 10.55 m wide in cross section(Two Lane Bridge with footpath). The bridge deck is 300 mm thick for inner panels. Traffic load as per IRC Class AA single train or two trains of Class A (IRC-6-2000). Portion of deck provide as a footpath is over hang for a clear length of 1.45 m on either side from the face of external girder rib. Page 36



D

Type of analysis/design adopted

E

If analysis, then Modelling method Carried out in which software (for analysis) Future scope of work

F G

Conclusions

Thickness of overhang portion of the deck is 300 mm at the face of external support which gradually reduces to 200 mm at free end.  A parapet wall or anti crash barrier is provided at the free end of the footpath of 200 mm thickness and 900 mm height while at the end of the overhang other side a median verge (divider) of 300 mm thickness and 240 mm depth is provided.  The present work was done to observe the behaviour of Integral Abutment Bridge while taking with and without spring analysis on the abutment wall and compare these two with the simply supported bridge, by using MIDAS CIVIL software.  Bridges were modelled for this work by using Midas Civil Software  Midas Civil Software 

There is much scope for further work in the area of IAB, Some of which are as below. o Nonlinear material models of concrete need to be implemented to study the long term effects of cyclic loading during the lifespan of the IAB. This will help in understanding cracking of concrete deck, girders and piles. o IAB could be analysed for longer and number of traffic lanes, considering skew ness of the substructure, it can be analysed for bridges with horizontal curves because many times it is not possible to have straight bridges especially in urban areas.



Near the junction of deck slab and abutment IAB has lesser stresses than SSB, because of rigid connection between abutment and deck slab, there is transfer of stresses, but in case of IAB WSA (Integral Abutment Bridge With Spring Analysis) the stresses is more as compare to SSB and less as compare to IAB because at ends abutments a spring force is develop. Bending moment is more in SSB as compare to IAB and bending moment is less in IAB

 INTEGRAL ABUTMENT BRIDGE

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WSA as compare to both. Overall we can say that moment and shear stress developed in various components of IAB is higher than SSB, so it can be concluded that moments, stresses and forces developed in IAB is higher than the equivalent SSB because of monolithic connection between various components of the bridge, but if we provide spring analysis at both ends of the end abutment then the shear force, bending moment and forces will reduce as compare to IAB.

INTEGRAL ABUTMENT BRIDGE

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3.9.

A COMPARATIVE STUDY OF CONVENTIONAL RC GIRDER BRIDGE AND INTEGRAL BRIDGE

Title Journal Name Year Publishing Sr. No. A

B

A Comparative study of Conventional RC Girder Bridge and Integral Bridge International Journal of Civil Engineering and Applications of 2016

Details Objective of study



Need of study



 C

Parameters considered

      

INTEGRAL ABUTMENT BRIDGE

A comparative study is carried out on a typical integral bridge and a conventional simply supported RC girder bridge of same geometry and loading conditions. The main objective of the study is to understand the structural behaviour in terms of bending moment, shear force and displacement of integral bridge and conventional simply supported bridge. The major advantages of integral bridges are absence of sliding bearings and expansion joints in the deck, economic construction and simple construction procedure, better seismic performance, high strength and pleasing aesthetics. Some limitations on the geometry of these bridges are being imposed like; limits on total length of bridge, horizontal alignment, vertical grade and skew angle. So for above mentioned advantages and limitations over bearing bridge IAB is studied The total length of bridge is 60m measured between two dirt walls. Bridge is divided into 3 spans, each span is 20m. The bridge deck is 250mm thick. Carriage way width is 7.5m Total width of the bridge is 12m in cross section (two lanes with footpath). Intermediate Cross girders are 0.6m in width, 1.7m in depth and 5m c/c and end cross girders are 0.6m in width and 1.7m in depth. Portion of deck provided as footpath is overhang for a clear length of 2m on either Page 39



D E F G

Type of analysis/design adopted If analysis, then Modelling method Carried out in which software (for analysis) Conclusion

  

 

INTEGRAL ABUTMENT BRIDGE

side from the face of external girder rib. A parapet wall or anti crash barrier is provided at the free end of the footpath of 250mm thick and 900mm height at the end of overhang.

Grillage analysis was used to model the bridge deck. The bridges were modelled and analysed in STAAD Pro. The maximum bending moment for the outer girder in integral bridge is less as compared to the conventional bridge. The reduction in bending moment is almost 60% in integral bridge and hence it is economical. The shear force in both the bridge is approximately same and no much deviation of results was observed. The maximum deflection in integral bridges was very less as compared to the conventional bridge. The reduction is quite evident and is almost 70% less.

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3.10.

BEHAVIOR OF INTEGRAL ABUTMENT BRIDGE WITH SPRING ANALYSIS

Title

Journal Name Year Publishing Sr. No. A

BEHAVIOR OF INTEGRAL ABUTMENT BRIDGE WITH SPRING ANALYSIS International Journal of Mechanical And Production Engineering of Aug 2014

Details Objective of study



B

Need of study



C

Parameters considered



    

D E F G

Type of analysis/design adopted If analysis, then Modelling method Carried out in which software (for analysis) Conclusions

    

INTEGRAL ABUTMENT BRIDGE

To get a better understanding of the behavior of IAB in different situation, a comparative study is carried out on a typical IAB and a simply supported bridge (SSB) of same geometry and loading conditions, and compares these bridges with spring and without spring analysis at both ends. To understand behaviour of Integral abutment bridge compare to simply supported bridge and to understand the effect of spring analysis. The bridge under consideration is an RCC Fly Over(T-beam) bridge of 150 m total length between two abutments excluding the length of approach slabs on either side. No of span = 7 Span length = 21.5 m Width of bridge = 10.55 m Thickness of bridge deck = 300 mm Traffic load considers as per IRC Class AA single train or two trains of Class A (IRC 62000) Three bridges are designed and analysed by spring analysis. Grillage analogy is used for modelling. Bridges were analysed for this work by using Midas Civil Software. Near the junction of deck slab and abutment IAB has lesser stresses than SSB. In case of Integral Abutment Bridge With Page 41

 

INTEGRAL ABUTMENT BRIDGE

Spring Analysis the stresses is more as compare to SSB and less as compare to IAB because at ends abutments a spring force is develop. Bending moment is more in SSB as compare to IAB and bending moment is less in IAB WSA as compare to both. Overall we can say that moment and shear stress developed in various components of IAB is higher than SSB, so it can be concluded that moments, stresses and forces developed in IAB is higher than the equivalent SSB because of monolithic connection between various components of the bridge, but if we provide spring analysis at both ends of the end abutment then the shear force, bending moment and forces will reduce as compare to IAB

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