Unit 48: Structural Behaviour and Detailing for Construction. Limit State Design
|
|
- Austin Reeves
- 6 years ago
- Views:
Transcription
1 2.1 Introduction Limit State Design Limit state design of an engineering structure must ensure that (1) under the worst loadings the structure is safe, and (2) during normal working conditions the deformation of the members does not detract from the appearance, durability or performance of the structure. Despite the difficulty in assessing the precise loading and variations in the strength of the concrete and steel, these requirements have to be met. Three basic methods using factors of safety to achieve safe, workable structures have been developed over many years; they are 1. The permissible stress method in which ultimate strengths of the materials are divided by a factor of safety to provide design stresses which are usually within the elastic range. 2. The load factor method in which the working loads are multiplied by a factor of safety. 3. The limit state method which multiplies the working loads by partial factors of safety and also divides the materials ultimate strengths by further partial factors of safety. The permissible stress method has proved to be a simple and useful method but it does have some serious inconsistencies and is generally no longer in use. Because it is based on an elastic stress distribution, it is not really applicable to a semi-plastic material such as concrete, nor is it suitable when the deformations are not proportional to the load, as in slender columns. It has also been found to be unsafe when dealing with the stability of structure subject to overturning forces. Jesmond Agius: Chapter 2 Page 1
2 In the load factor method the ultimate strength of the materials should be used in the calculations. As this method does not apply factors of safety to the material stresses, it cannot directly take account of the variability of the materials, and also it cannot be used to calculate the deflections or cracking at working loads. Again, this is a design method that has now been effectively superseded by modern limit state design methods. The limit state method of design, now widely adopted across Europe and many other parts of the world, overcome many of the disadvantages of the previous two methods. It does so by applying partial factors of safety, both to the loads and to the material strengths, and the magnitude of the factors may be varied so that they be used either with the plastic conditions in the ultimate state or with the more elastic range stress range at working loads. This flexibility is particularly important if full benefits are to be obtained from development of improved concrete and steel properties. 2.2 Limit States The purpose of design is to achieve acceptable probabilities that a structure will not become unfit for its intended use that is, that it will not reach a limit state. Thus, any way in which a structure may cease to be fit for use will constitute a limit state and the design aim is to avoid any such condition being reached during the expected life of the structure. The two principle types of limit state are the ultimate limit and the serviceability limit state. (a) Ultimate limit state This requires that the structure must be able to withstand, with an adequate factor of safety against collapse, the loads for which it is designed to ensure the safety of the building occupants and/or the safety of the structure itself. The possibility of buckling or overturning must also be taken into account, as must the possibility of the accidental damage as caused, for example, by an internal explosion. (b) Serviceability limit states Generally the most important serviceability limit states are: 1. Deflection- the appearance or efficiency of any part of the structure must not be adversely affected by deflections nor should the comfort of the building users be adversely affected. 2. Cracking- local damage due to cracking and spalling must not affect the appearance, efficiency or durability of the structure. Jesmond Agius: Chapter 2 Page 2
3 3. Durability this must be considered in terms of the proposed life of the structure and its conditions of exposure. Other limit states that may be reached include: 4. Excessive vibration which may cause discomfort or alarm as well as damage. 5. Fatigue must be considered if cyclic loading is likely. 6. Fire resistance this must be considered in terms of resistance to collapse, flame penetration and heat transfer. 7. Special circumstances any special requirements of the structure which are not covered by any of the more common limit states, such as earthquake resistance, must be taken into account. The relative importance of each limit state will vary according to the nature of the structure. The usual procedure is to decide which is the crucial limit state for a particular structure and base the design on this, although durability and fire resistance requirements may well influence member sizing and concrete class selection. Checks must also be made to ensure that all other relevant limit states are satisfied by the results produced. Except in special cases, such as waterretaining structures, the ultimate limit state is generally critical for reinforced concrete although subsequent serviceability checks may affect some of the details of the design. Prestressed concrete design, however, is generally based on serviceability conditions with checks on the ultimate limit state. In assessing a particular limit state for a structure it is necessary to consider all the possible variable parameters such as the loads, material strengths and all constructional tolerances. 2.3 Characteristic Material Strengths and Characteristic Loads Characteristic Material Strengths The strengths of materials upon which a design is based are, normally, those strengths below which results are unlikely to fall. These are called characteristic strengths. It is assumed that for a given material, the distribution of strength will be approximately normal, so that a frequency distribution curve of a large number of sample results would be of the form shown in the next figure. The characteristic strength is taken as that value below which it is unlikely that more than 5 per cent of the results will fall. This is given by where = characteristic strength, Jesmond Agius: Chapter 2 Page 3
4 = mean strength and S = standard deviation ( ). n = number of tested specimens or samples and x i = individual test results The relationship between characteristic and mean values accounts for variations in results of test specimens and will, therefore, reflect the method and control of manufacture, quality of constituents, and nature of the material Characteristic Actions Figure 1: Normal Frequency Distribution of Strengths In Eurocode terminology the set of applied forces (or loads) for which a structure is to be designed are called actions although the terms actions and loads tend to be used interchangeable in some of the Eurocodes. Actions can also have a wider meaning including the effect of imposed deformations caused by, for example, settlement of foundations. In this text we will standardise on the term actions as much as possible. Ideally it should be possible to assess actions statistically in the same way that material characteristic strengths can be determined statistically, in which case Jesmond Agius: Chapter 2 Page 4
5 Characteristic action = mean action 1.64 standard deviations In most cases it is the maximum value of the actions on a structural member that is critical and the upper, positive value given by this expression is used; but the lower, minimum value may apply when considering stability or the behaviour of continuous members. These characteristic values represent the limits within which at least 90 per cent of values will lie in practice. It is to be expected that not more than 5 per cent of cases will exceed the upper limit and not more than 5 per cent will fall below the lower limit. They are design values that take into account the accuracy with which the structural loading can be predicted. Usually, however, there is insufficient statistical data to allow actions to be treated in this way, and in this case the standard loadings, such as those given in BS EN 1991, Eurocode 1 Actions on Structures, should be used as representing characteristic values. Figure 2: Characteristic Strength f k for two Materials Jesmond Agius: Chapter 2 Page 5
6 Example 1 Calculation of, the characteristic strength of a material. The following table shows the results of 14 compressive strength tests of steel bars made under the same conditions. 1. Determine the characteristic strength of the material tested. 2. Determine the compressive strength above which only 5 percent of the results are likely to fall. 3. Draw the normal distribution curve for the results. Test Values, x i (N/mm 2 ) Answer Sum of Test values = = therefore mean value = x i (N/mm 2 ) ( ) x i (N/mm 2 ) ( ) therefore sum of ( ) S = standard deviation ( ) So the characteristic strength Characteristic Strength above which 5% of results are likely to fall Jesmond Agius: Chapter 2 Page 6
7 Number of Tested Samples Unit 48: Structural Behaviour and Detailing for Construction Continue the following table of the range of compressive strengths and finally draw the normal distribution curve from the results. Range of compressive strength (N/mm 2 ) Number of tested samples Normal Distribution Curve Compressive Strength (N/mm 2 ) Jesmond Agius: Chapter 2 Page 7
8 2.4 Partial Factors of Safety Other possible variations such as constructional tolerances are allowed for by partial factors of safety applied to the strength of the materials and to the actions. It should theoretically be possible to derive values for these from a mathematical assessment of the probability of reaching each limit state. Lack of adequate data, however, makes this unrealistic and, in practise, the values adopted are based on experience and simplified calculations Partial Factors of Safety for Materials ( m ) ( ) ( ) The following factors are considered when selecting a suitable value for m: 1. The strength of the material in an actual member. This strength will differ from that measured in a carefully prepared test specimen and it is particularly true for concrete where placing, compaction and curing area so important to the strength. Steel, on the other hand, is a relatively consistent material requiring a small partial factor of safety. 2. The severity of the limit state being considered. Thus, higher values are taken for the ultimate limit state than for the serviceability limit state. Recommended values for m are given in the next table. The values in the first two columns should be used when the structure is being designed for persistent design situations (anticipated normal usage) or transient design situations (temporary situations such as may occur during construction). The values in the last two columns should be used when the structure is being designed for exceptional accidental design situations such as the effects of fire or explosion. Figure 3: Partial Factors of Safety applied to materials ( m ) Jesmond Agius: Chapter 2 Page 8
9 2.4.2 Partial Factors of Safety for Actions ( f ) Errors and inaccuracies may be due to a number of causes: 1. Design assumptions and inaccuracy of calculation; 2. Possible unusual increases in the magnitude of the actions; 3. Unforeseen stress redistributions; 4. Constructional inaccuracies. These cannot be ignored, and are taken into account by applying a partial factor of safety ( f ) on the characteristic actions, so that Design value of action = characteristics action partial factor of safety ( f ) The value of this factor should also take into account this importance of the limit state under consideration and reflects to some extent the accuracy with which different types of actions can be predicted, and the probability of particular combinations of actions occurring. It should be noted that design errors and constructional inaccuracies have similar effects and are thus sensibly grouped together. These factors will account adequately for normal conditions although gross errors in design or construction obviously cannot be catered for. Recommended values of partial factors of safety are given in tables 2.2 and 2.3 according to the different categorisations of actions shown in the tables. Actions are categorised as either permanent (G k ), such as the self-weight of the structure, or variable (Q k ), such as the temporary imposed loading arising from the traffic of people, wind and snow loading, and the like. Variable actions are also categorised as leading (the predominant variable action on the structure such as an imposed crowd load Q k, 1 ) and accompanying (secondary variable action(s) such as the effect of wind loading, Q k, i, where the subscript i' indicates the i'th action). The terms favourable and unfavourable refer to the effect of the action (s) on the design situation under consideration. For example, if a beam, continuous over several spans, is to be designed for the largest sagging bending moment it will have to sustain any action that has the effect of increasing the bending moment will be considered unfavourable whilst any action that reduces the bending moment will be considered to be favourable. Jesmond Agius: Chapter 2 Page 9
10 Figure 4: Partial Safety Factors at the Ultimate Limit State Figure 5: Partial Safety Factors at the Serviceability Limit State The next example shows how the partial safety factors at the ultimate limit state from tables 2.1 and 2.2 are used to design the cross-sectional area of a steel cable supporting permanent and variable actions. Example 2 SIMPLE DESIGN OF A CABLE AT THE ULTIMATE LIMIT STATE Determine the cross-sectional area of steel required for a cable which supports a total characteristic permanent action of 3.0 kn and a characteristic variable action of 2.0 kn as shown in this figure. Jesmond Agius: Chapter 2 Page 10
11 The characteristic yield stress of the steel is 500 N/mm 2. Carry out the calculation using limit state design with the following factors of safety : Answer G =1.35 for the permanent action, Q =1.5 for the variable action, and m =1.15 for the steel strength. Design value = G permanent action Q variable action = = 7.05 kn = 4.34 N/mm 2 Required cross-sectional area = = 16.2 mm 2 For convenience, the partial factors of safety in the example are the same as those recommended in EC2. Probably, in a practical design, higher factors of safety would be preferred for a single supporting cable, in view of the consequences of a failure. Example 3 shows the design of a foundation to resist uplift at the ultimate limit state using the partial factors of safety from figure 4. It demonstrates the benefits of using the limit state approach instead of the potentially unsafe overall factor of safety design used in part (b). Jesmond Agius: Chapter 2 Page 11
12 Example 3 The next figure shows a beam supported on foundations at A and B. The loads supported by the beam are its own uniformly distributed permanent weight of 20kN/m and a 170kN variable load concentrated at end C. Determine the weight of the foundation required at A in order to resist uplift: (a) By applying a factor of safety of 2.0 to the reaction calculated for the working loads. (b) By using an ultimate limit state approach with partial factors of safety of G = 1.10 or 0.9 for the permanent action and G = 1.5 for the variable action. (c) Investigate the effect on these designs of a 7 per cent increase in the variable action. Figure 6: Uplift Calculation Example Jesmond Agius: Chapter 2 Page 12
13 Answer (a) Factor of safety on uplift = 2.0 Taking moments about B Uplift ( ) Weight of foundation required = R A x safety factor = 3.33 x 2.0 = 6.7 kn With a 7 per cent increase in the variable action Uplift ( ) Thus with a slight increase in the variable action there is a significant increase in the uplift and the structure becomes unsafe. (b) Limit state method ultimate load pattern As the example includes a cantilever and also involves the requirement for static equilibrium at A, partial factors of safety of 1.10 and 0.9 were chosen for the permanent actions as given in the first row of values in figure 4. The arrangement of the loads for the maximum uplift at A is shown in figure 6b. Design permanent action over BC = G 20 2 = = 44 kn Design permanent action over AB = G 20 6 = = 108 kn Design variable action = Q 170 = = 255 kn Taking moments about B for the ultimate actions Uplift ( ) Therefore weight of foundation required = 38 kn. A 7 per cent increase in the variable action will not endanger the structure, since the actual uplift will only be 7.3 kn as calculated previously. In fact in this case it would require an increase of 61 per cent in the variable load before the uplift would exceed the weight of a 38 kn foundation. Jesmond Agius: Chapter 2 Page 13
14 Exercise Explain what is meant by the following: a. Permissible stress, load factor and limit state design methods. b. Characteristic strength c. Characteristic loads 2. Explain why the partial factors of safety for materials are incorporated when the limit state design method is used. 3. Determine the cross-sectional area and the diameter of a circular mild steel bar that is required to safely support a dead load of 10kN and an imposed load of 6kN (see next figure). The yield stress (ultimate strength) of mild steel is 250N/mm 2. Use a factor of safety of 1.8 for the material strength. Use all the three design methods and critically comment on your results. a a Section a-a 10kN 6kN 4. The results shown in the following table are the compressive strengths of 20 steel bars made under the same conditions. a. Determine the characteristic strength of the materials. b. Determine the compressive strength above which only 5 percent of the tested results are likely to fall. c. Draw the normal frequency distribution curve of compressive strength, mark f k and f m on the distribution curve. d. Write a computer program to solve this question. Compressive Strength of Steel Samples (N/mm 2 ) Jesmond Agius: Chapter 2 Page 14
mortarless masonry Design Manual Part 1 (IS 456:2000) Section 1 Page 1 IS 456:2000 PLAIN AND REINFORCED CONCRETE - CODE OF PRACTICE
SECTION 1. mortarless masonry Design Manual Part 1 (IS 456:2000) Section 1 Page 1 1.1 Overview of IS 456:2000 IS 456:2000 PLAIN AND REINFORCED CONCRETE - CODE OF PRACTICE IS 456:2000 is the current Indian
More informationFlexure and Serviceability Limit State
UNIT 3 Flexure and Serviceability Limit State Beam A structural member that support transverse (Perpendicular to the axis of the member) load is called a beam. Beams are subjected to bending moment and
More information2016 DESIGN AND DRAWING OF REINFORCED CONCRETE STRUCTURES
R13 SET - 1 DESIGN AND DRAWING OF REINFCED CONCRETE STRUCTURES 1 Design a simply supported rectangular beam to carry 30kN/m superimposed load over a span of 6m on 460mm wide supports. Use M20 grade concrete
More informationCHAPTER 2. Design Formulae for Bending
CHAPTER 2 Design Formulae for Bending Learning Objectives Appreciate the stress-strain properties of concrete and steel for R.C. design Appreciate the derivation of the design formulae for bending Apply
More information2. LIMIT STATE DESIGN
2. LIMIT STATE DESIGN 2.1 Introduction to Limit State Design A Civil Engineering Designer has to ensure that the structures and facilities he designs are (i) fit for their purpose (ii) safe and (iii) economical
More informationST7008 PRESTRESSED CONCRETE
ST7008 PRESTRESSED CONCRETE QUESTION BANK UNIT-I PRINCIPLES OF PRESTRESSING PART-A 1. Define modular ratio. 2. What is meant by creep coefficient? 3. Is the deflection control essential? Discuss. 4. Give
More informationIntroduction. Structures may be classified on the basis of materials used for construction, as follows: Steel structures. Aluminium structures
Steel Structures 1 Introduction Structures may be classified on the basis of materials used for construction, as follows: Steel structures Aluminium structures Concrete structures Composite structures
More informationReinforced and Prestressed Concrete Design
12 Reinforced and Prestressed Concrete Design S C C Bate CBE, BSc(Eng), PhD, C Eng, FIStructE, FICE Formerly at the Building Research Establishment and later, currently Consultant to Harry Stanger Ltd
More informationRecommendations for additional fire protection of structural elements
ANNEX 6 Recommendations for additional fire protection of structural elements 1 Scope This Annex contains a series of recommendations applicable to structural concrete structures which, for general fire
More informationFundamentals of Structural Design Part of Steel Structures
Fundamentals of Structural Design Part of Steel Structures Civil Engineering for Bachelors 133FSTD Teacher: Zdeněk Sokol Office number: B619 1 Syllabus of lectures 1. Introduction, history of steel structures,
More informationASSIGNMENT 1 ANALYSIS OF PRESTRESS AND BENDING STRESS BFS 40303
Instruction : Answer all question ASSIGNMENT 1 ANALYSIS OF PRESTRESS AND BENDING STRESS BFS 40303 1. A rectangular concrete beam, 100 mm wide by 250 mm deep, spanning over 8 m is prestressed by a straight
More informationThe Edge Protection Federation Containment Systems Product Specification, Test Methods
The Edge Protection Federation Containment Systems Product Specification, Test Methods Revision 2 August 2016 This Standard defines how the Edge Protection Federation defines Containment. This document
More informationBS EN :2004 EN :2004 (E)
Contents List 1. General 1.1 Scope 1.1.1 Scope of Eurocode 2 1.1.2 Scope of Part 1-1 of Eurocode 2 1.2 Normative references 1.2.1 General reference standards 1.2.2 Other reference standards 1.3 Assumptions
More informationQUESTION BANK CE6702 PRESTRESSED CONCRETE STRUCTURES UNIT 3 - DEFLECTION AND DESIGN OF ANCHORAGE ZONE PART A (2 marks) 1. What are the functions of water stopper (water bar) in water tank construction?
More informationPRESTRESSED CONCRETE STRUCTURES. Amlan K. Sengupta, PhD PE Department of Civil Engineering Indian Institute of Technology Madras
PRESTRESSED CONCRETE STRUCTURES Amlan K. Sengupta, PhD PE Department of Civil Engineering Indian Institute of Technology Madras Module - 4: Design of Members Lecture - 17: Design of Members for Axial Tension
More informationCOLUMNS. Classification of columns:
COLUMNS are vertical compression members in structures, the effective length of which exceeds three times its lateral dimension. Which are provided for bear the load of Beam, Slab, etc. since columns support
More informationmortarless Design Manual Part 1 (AS 3600:2009) Section 1 Page 1 AS 3600:2009 PLAIN AND REINFORCED CONCRETE - CODE OF PRACTICE
SECTION 1. mortarless Design Manual Part 1 (AS 3600:2009) Section 1 Page 1 AS 3600:2009 PLAIN AND REINFORCED CONCRETE - CODE OF PRACTICE 1.1 Overview of AS 3600:2009 AS 3600:2009 is the latest Australian
More informationColumn: Part 2 Courtesy of Dr. Latifee s IMI research group, Text books and others
Column: Part 2 Courtesy of Dr. Latifee s IMI research group, Text books and others Design for Axial Load: With negligible moment and considerable amount of concentric axial load, failure occurs when the
More informationEurocodes European Codes for Structural Design. H. J. Bossenmayer, Prof. Dr.-Ing., is president, Deutsches Institut für Bautechnik, Berlin, Germany
Eurocodes European Codes for Structural Design H. J. Bossenmayer, Prof. Dr.-Ing., is president, Deutsches Institut für Bautechnik, Berlin, Germany ABSTRACT The structural Eurocodes are an unrivalled set
More informationLevel 6 Graduate Diploma in Engineering Structural analysis
9210-111 Level 6 Graduate Diploma in Engineering Structural analysis Sample Paper You should have the following for this examination one answer book non-programmable calculator pen, pencil, ruler, drawing
More informationGATE SOLVED PAPER - CE
YEAR 2013 Q. 1 Maximum possible value of compaction factor for fresh (green) concrete is (A) 0.5 (B) 1.0 (C) 1.5 (D) 2.0 Q. 2 As per IS 456 : 2000, bond strength of concrete t bd = 12. for M20. It is increased
More informationElastic versus Plastic Analysis of Structures
Elastic versus Plastic Analysis of Structures 1.1 Stress-Strain Relationships 1.2 Plastic Design Versus Elastic Design Chapter 1 Basic Concepts of Plastic Analysis 1.3 Elastic-Plastic Bending of Beams
More informationCE 315: Design of Concrete Structures I
CE 315: Design of Concrete Structures I Dr. Tahsin Reza Hossain Professor, Room No-649 Email: tahsin@ce.buet.ac.bd Syllabus New Fundamental behavior of reinforced concrete Introduction to strength design
More informationPRINCIPLES OF CONCRETE DESIGN
29 PRINCIPLES OF CONCRETE DESIGN Actions on structures and Limit state method Beams Columns Slabs Frames Special Structures MITOITUSPERUSTEET- osio Kuormitukset ja osavarmuuskerroinmenettely Palkit Pilarit
More informationIntroduction to Structural Analysis TYPES OF STRUCTURES LOADS AND
AND Introduction to Structural Analysis TYPES OF STRUCTURES LOADS INTRODUCTION What is the role of structural analysis in structural engineering projects? Structural engineering is the science and art
More informationCHAPTER 1 INTRODUCTION 1.1 MOMENT END-PLATE CONNECTIONS
CHAPTER 1 INTRODUCTION 1.1 MOMENT END-PLATE CONNECTIONS The typical moment end-plate connection shown in Fig. 1-1 consists of a plate that is shop-welded to the end of a beam which is then bolted to the
More informationContinuous Beam Design with Moment Redistribution (CSA A )
Continuous Beam Design with Moment Redistribution (CSA A23.3-14) Continuous Beam Design with Moment Redistribution (CSA A23.3-14) A structural reinforced concrete continuous beam at an intermediate floor
More informationReinforced Concrete Design. A Fundamental Approach - Fifth Edition
CHAPTER REINFORCED CONCRETE Reinforced Concrete Design A Fundamental Approach - Fifth Edition Fifth Edition REINFORCED CONCRETE A. J. Clark School of Engineering Department of Civil and Environmental Engineering
More informationAbstract. 1 Introduction
Ultimate deformation capacity of reinforced concrete slabs under blast load J.C.A.M. van Doormaal, J. Weeheijm TNO PrinsMaurits Laboratory, P.O. Box 45, 2280 AA Rijswijk, The Netherlands Abstract In this
More information10-COLUMNS: 10.1 Introduction.
1 10-COLUMNS: 10.1 Introduction. Columns are vertical compression members of a structural frame intended to support the loadcarrying beams. They transmit loads from the upper floors to the lower levels
More informationConcept of Prestressing
Concept of Prestressing Concept of Prestressing Prestressing the concrete is to transfer precompression (compressive stress) to the concrete How the prestressing force transmitted to concrete can be explained
More informationContents. Foreword 1 Introduction 1
Contents Notation x Foreword xiii 1 Introduction 1 1.1 Aims of the Manual 1 1.2 Eurocode system 1 1.3 Scope of the Manual 3 1.4 Contents of the Manual 4 1.5 Notation and terminology 4 2 General principles
More informationModelling of Long-Term Loading Tests on Reinforced Concrete Beams N. Reybrouck; P. Criel; R. Caspeele; and L. Taerwe
CONCREEP 10 745 Modelling of Long-Term Loading Tests on Reinforced Concrete Beams N. Reybrouck; P. Criel; R. Caspeele; and L. Taerwe Magnel Laboratory for Concrete Research, Department of Structural Engineering,
More information10.5 ECCENTRICALLY LOADED COLUMNS: AXIAL LOAD AND BENDING.
13 10.5 ECCENTRICALLY LOADED COLUMNS: AXIAL LOAD AND BENDING. Members that are axially, i.e., concentrically, compressed occur rarely, if ever, in buildings and other structures. Components such as columns
More informationStructural requirements
Chapter 2 Structural requirements 2.1 Introduction To perform its function of supporting a building in response to whatever loads may be applied to it, a structure must possess four properties: it must
More informationUltimate Limit State: Bending
Ultimate Limit State: Bending Presented by: John Robberts Design Point Consulting Engineers (Pty) Ltd john.robberts@design-point.co.za ULS: Flexure with and without axial force fundamental principles There
More informationDesign of Composite Bridges Use of BS 5400: Part 5: 1979
THE HIGHWAYS AGENCY THE SCOTTISH OFFICE DEVELOPMENT DEPARTMENT Amendment No.1, dated 10 December 1987 THE WELSH OFFICE Y SWYDDFA GYMREIG THE DEPARTMENT OF THE ENVIRONMENT FOR NORTHERN IRELAND Design of
More informationBasic quantities of earthquake engineering. Strength Stiffness - Ductility
Basic quantities of earthquake engineering Strength Stiffness - Ductility 1 Stength is the ability to withstand applied forces. For example a concrete element is weak in tension but strong in compression.
More informationPRESTRESSED CONCRETE STRUCTURES UNIT I INTRODUCTION THEORY AND BEHAVIOUR
BASIC CONCEPTS: PRESTRESSED CONCRETE STRUCTURES UNIT I INTRODUCTION THEORY AND BEHAVIOUR A prestressed concrete structure is different from a conventional reinforced concrete structure due to the application
More informationVARIOUS TYPES OF SLABS
VARIOUS TYPES OF SLABS 1 CHOICE OF TYPE OF SLAB FLOOR The choice of type of slab for a particular floor depends on many factors. Economy of construction is obviously an important consideration, but this
More information5.2 Design values of material coefficient (BS EN :2005)
5.2 Design values of material coefficient (BS EN 1993-1-1:2005) Modulus of elasticity (E) = 210 000 N/mm2. Shear modulus (G) = E/2(1+v) = 81 000N/mm2. Poisson s ratio (v) = 0.3. Coefficient of linear thermal
More informationLecture Retaining Wall Week 12
Lecture Retaining Wall Week 12 Retaining walls which provide lateral support to earth fill embankment or any other form of material which they retain them in vertical position. These walls are also usually
More informationFIBRE REINFORCED CONCRETE FOR PRECAST TUNNEL SEGMENTS
FIBRE REINFORCED CONCRETE FOR PRECAST TUNNEL SEGMENTS Jan L. Vítek 1, Matouš Hilar 2, Petr Vítek 3 Abstract: Fibre reinforced concrete is a promising material for application in precast concrete tunnel
More informationTheory Composite Beam Design
Theory Composite Beam Design Composite Beam Design Theoretical Background Introduction... 1 Composite beam design... 2 Design check to BS 5950-3.1...2 References...5 Fire resistance check to BS 5950-8...5
More informationHours / 100 Marks Seat No.
17422 21314 4 Hours / 100 Seat No. Instructions (1) All Questions are Compulsory. (2) Answer each next main Question on a new page. (3) Illustrate your answers with neat sketches wherever necessary. (4)
More informationCOVENANT UNIVERSITY ALPHA SEMESTER TUTORIAL KIT (VOL. 2) 400 LEVEL
COVENANT UNIVERSITY ALPHA SEMESTER TUTORIAL KIT (VOL. 2) P R O G R A M M E : B U I L D I N G T EC H 400 LEVEL DISCLAIMER The contents of this document are intended for practice and learning purposes at
More informationCYCLIC RESPONSE OF RC HOLLOW BOX BRIDGE COLUMNS STRENGTHENED USING CFRP AND RC JACKETING
CYCLIC RESPONSE OF RC HOLLOW BOX BRIDGE COLUMNS STRENGTHENED USING CFRP AND RC JACKETING Tatjana ISAKOVIC Professor University or Ljubljana, Faculty of Civil and Geodetic Engineering Jamova 2, 1000 Ljubljana,
More informationGeneral Structural Concerns
1/28 General Structural Concerns Functionality / Stiffness deformations Stability equilibrium Strength material behaviour 2/28 Stability Loads act on structure tend to destabilise structure also tend to
More informationInfluence of arch bridge skewness
EUROSTEEL 2017, September 13 15, 2017, Copenhagen, Denmark ABSTRACT Influence of arch bridge skewness Hans De Backer*,a, Amelie Outtier a, Evy Van Puymbroeck*,a, Philippe Van Bogaert a a Ghent University,
More informationCHAPTER 5 BEHAVIOUR OF BEAM-COLUMN JOINT UNDER CYCLIC LOADING
72 CHAPTER 5 BEHAVIOUR OF BEAM-COLUMN JOINT UNDER CYCLIC LOADING 5.1 GENERAL In this chapter the behaviour of beam-column joints cast using M20 and M25 concrete under cyclic loading have been enumerated.
More informationMarian A. GIZEJOWSKI Leslaw KWASNIEWSKI Wael SALAH
Robustness of continuous steel-concrete composite beams of slender plain webbed and cellular open webbed sections Marian A. GIZEJOWSKI Leslaw KWASNIEWSKI Wael SALAH Faculty of Civil Engineering Warsaw
More informationBEHAVIOUR OF REINFORCED CONCRETE STRUCTURES IN FIRE
BEHAVIOUR OF REINFORCED CONCRETE STRUCTURES IN FIRE ZHAOHUI HUANG, IAN W. BURGESS and ROGER J. PLANK 3 ABSTRACT In the past two decades, a significant amount of research has been conducted into the performance
More informationDiploma in Civil Engineering. Term-End Examination June, BCE-041 : THEORY OF STRUCTURES II
No. of Printed Pages : 6 BCE-041 Diploma in Civil Engineering Term-End Examination June, 2012 00819 BCE-041 : THEORY OF STRUCTURES II Time : 2 hours Maximum Marks : 70 Note : Question number 1 is compulsory.
More informationVertical Incremental Dynamic Analysis for Assessing Progressive Collapse Resistance and Failure Modes of Structures
The 4th International Workshop on Reliable Engineering Computing (REC 2010) Vertical Incremental Dynamic Analysis for Assessing Progressive Collapse Resistance and Failure Modes of Structures Dagang Lu,
More informationTable of contents. EC3 Steel Design - Class 4 calculation of effective characteristics... 5
What's New 2018 R2 Table of contents NEW OPTIONS & IMPROVEMENTS... 5 EC3 Steel Design - Class 4 calculation of effective characteristics... 5 Optimization of theoretical reinforcement according to EC2
More informationSIMPLIFIED ESTIMATION OF CRITICAL TEMPERATURES OF PORTAL FRAMES IN FIRE
SIMPLIFIED ESTIMATION OF CRITICAL TEMPERATURES OF PORTAL FRAMES IN FIRE by S.Y. Wong 1, I.W. Burgess 1 and R.J. Plank 2 1 Department of Civil & Structural Engineering, University of Sheffield, UK. 2 School
More informationA simple computational tool for the verification of concrete walls reinforced by embedded steel profiles.
A simple computational tool for the verification of concrete walls reinforced by embedded steel profiles. T. Bogdan, H. Degée, A. Plumier University of Liège, Belgium C. Campian Technical University of
More informationThe concept of statical determinacy
Appendix 3 The concept of statical determinacy 140 A3.1 Introduction It has been shown that the conditions for equilibrium of a set of coplanar forces can be summarised in the three equations of equilibrium
More informationOXFORD ENGINEERING COLLEGE (NAAC Accredited with B Grade) Department of Civil Engineering LIST OF QUESTIONS
OXFORD ENGINEERING COLLEGE (NAAC Accredited with B Grade) Department of Civil Engineering LIST OF QUESTIONS Year/ Sem. : IV / VII Staff Name : S.LUMINA JUDITH Subject Code : CE 6702 Sub. Name : PRE STRESSED
More informationConcrete Design Guide
Number 7 38 TheStructuralEngineer Technical July 2015 Post-tensioned slabs Concrete Design Guide No. 7: Design of post-tensioned slabs This series is produced by The Concrete Centre to enable designers
More informationStructural Mechanics in Construction and Civil Engineering
Unit 14: Structural Mechanics in Construction and Civil Engineering NQF Level 3: Guided learning hours: 60 BTEC National Unit abstract The study of the mechanics of structures is essential for engineers,
More informationTypes of Structures and Loads
Types of Structures and Loads THEORY OF STRUCTURES Asst. Prof. Dr. Cenk Üstündağ Asst. Prof. Dr. Cenk Ustundag E-mail: ustunda1@itu.edu.tr Room Nr: 103 Web: http://web.itu.edu.tr/ustunda1 Course Content
More informationAdvanced Eurocode Training. EN : Composite Structures
Advanced Eurocode Training EN 1994-1-1: Composite Structures Eurocode Training EN 1994-1-1 All information in this document is subject to modification without prior notice. No part of this manual may be
More informationPartial factors: where to apply them?
LSD2000: International Workshop on Limit State Design in Geotechnical Engineering Melbourne, Australia. 18 November 2000 Partial factors: where to apply them? Brian Simpson Arup Geotechnics, London, UK
More informationDEFLECTION OF STRAIGHT AND CAMBERED BEAMS MEASURED DURING FOURTEEN HOURS PER DAY
Number4 Volume13 December 006 Journal of Engineering DEFLECTION OF STRAIGHT AND CAMBERED BEAMS MEASURED DURING FOURTEEN HOURS PER DAY Dr. Kanaan Sliwo Youkhanna Athuraia ABSTRACT Straight and camber beams
More informationEurocode Training EN : Composite Structures
Eurocode Training EN 1994-1-1: Composite Structures All information in this document is subject to modification without prior notice. No part of this manual may be reproduced, stored in a database or retrieval
More informationCOMPOSITE STRUCTURES PREPARED BY : SHAMILAH
COMPOSITE STRUCTURES PREPARED BY : SHAMILAH ANUDAI@ANUAR INTRODUCTION Steel and Concrete Composite Construction Composite construction aims to make each material perform the function it is best at or to
More informationCHAPTER FIVE 5.1 MODELING OF A TEN-STOREY BUILDING
CHAPTER FIVE 5.1 MODELING OF A TEN-STOREY BUILDING Three simple multi-storey buildings for a typical office complex of structural beam floors were analyzed using PROKON finite element model package to
More informationConcrete Cracking. ε ctr = f ctr / E c = 0.6 / 4400 = x 10-3
Concrete Cracking Concrete is known as a sensitive material for cracking. The code defines concrete modulus of elasticity (E c ) and concrete cracking-limit tensile stress (f ctr ) as: E c = 4400 (f cu
More informationUNIT IVCOMPOSITE CONSTRUCTION PART A
UNIT IVCOMPOSITE CONSTRUCTION PART A 1. What is composite section of pestressed concrete? [A/M 16] A composite section in context of prestressed concrete members refers to a section with a precast member
More information1 Introduction. 1.1 Scope of this Manual. 1.2 Purpose
1 Introduction 1.1 Scope of this Manual This Manual proposes a systematic risk assessment framework for the design of high-risk structures against disproportionate collapse. Risk assessment is a requirement
More informationModule 2. Philosophies of Design by Limit State Method. Version 2 CE IIT, Kharagpur
Module 2 Philosophies of Design by Limit State Method Lesson 3 Philosophies of Design by Limit State Method Instructional Objectives: At the end of this lesson, the student should be able to: categorically
More informationENR202 Mechanics of Materials Lecture 1A Slides and Notes
Slide 1 Copyright Notice Do not remove this notice. COMMMONWEALTH OF AUSTRALIA Copyright Regulations 1969 WARNING This material has been produced and communicated to you by or on behalf of the University
More informationStay Tuned! Practical Cable Stayed Bridge Design
midas Civil Stay Tuned! Practical Cable Stayed Bridge Design 2017 Francesco Incelli I. Introduction II. Modeling of the cable-stayed bridge a. Bridge wizard b. Girder Cross Section III. Nonlinear Effect
More informationPerformance based Displacement Limits for Reinforced Concrete Columns under Flexure
Performance based Displacement Limits for Reinforced Concrete Columns under Flexure Ahmet Yakut, Taylan Solmaz Earthquake Engineering Research Center, Middle East Technical University, Ankara,Turkey SUMMARY:
More informationCD 360 Use of Compressive Membrane Action in Bridge Decks
Design Manual for Roads and Bridges Highway Structures & Bridges Design CD 360 Use of Compressive Membrane Action in Bridge Decks (formerly BD 81/02) Revision 1 Summary This document provides requirements
More informationThe Mathematics of Material Quality Control
The Mathematics of Material Quality Control Scenario You are working in a materials testing laboratory with specific responsibility for testing and monitoring the strength of concrete specimens as they
More information3.4.2 DESIGN CONSIDERATIONS
3.4.2 DESIGN CONSIDERATIONS Formwork Where Flatdeck sheet is used as formwork, the profile provides resistance to wet concrete (G) and construction loads (Q). Maximum formwork spans given in Section 3.4.4.1
More informationCOMPOSITE BRIDGES WITH PRECAST CONCRETE SLABS
COMPOSITE BRIDGES WITH PRECAST CONCRETE SLABS P. SCHAUMANN Univ.-Prof. Dr.-Ing. J. UPMEYER Dipl.-Ing. University of Hanover Institute for Steel Construction Appelstraße 9A 30167 Hanover / Germany Tel.:
More informationAppendix M 2010 AASHTO Bridge Committee Agenda Item
Appendix M 2010 AASHTO Bridge Committee Agenda Item 2010 AASHTO BRIDGE COMMITTEE AGENDA ITEM: SUBJECT: LRFD Bridge Design Specifications: Section 5, High-Strength Steel Reinforcement TECHNICAL COMMITTEE:
More information1 Prepared By:Mr.A.Sathiyamoorthy, M.E., AP/Civil
UNIVERSITY QUESTIONS PART A UNIT 1: INTRODUCTION THEORY AND BEHAVIOUR 1. List the loss of prestress. 2. Define axial prestressing. 3. What is the need for the use of high strength concrete and tensile
More informationModelling of shrinkage induced curvature of cracked concrete beams
Tailor Made Concrete Structures Walraven & Stoelhorst (eds) 2008 Taylor & Francis Group, London, ISBN 978-0-415-47535-8 Modelling of shrinkage induced curvature of cracked concrete beams R. Mu, J.P. Forth
More informationDESIGN OF RC ELEMENTS UNIT 1 PART-A
DESIGN OF RC ELEMENTS UNIT 1 PART-A 1. Calculate the design strength for M 30 grade concrete and Fe 415 grade steel? 2. What is the important principle of ultimate load method? 3. Write the classification
More informationCHAPTER 3 BEHAVIOUR OF FERROCEMENT HOLLOW SLABS
30 CHAPTER 3 BEHAVIOUR OF FERROCEMENT HOLLOW SLABS 3.1 INTRODUCTION There are numerous similarities between ferrocement and reinforced concrete. Both use similar matrix and reinforcement materials. They
More informationANALYTICAL STUDY OF PUNCHING SHEAR ON WAFFLE SLAB WITH DIFFERENT RIB SIZES
Jr. of Industrial Pollution Control 33(S2)(27) pp 323-327 www.icontrolpollution.com Research Article ANALYTICAL STUDY OF PUNCHING SHEAR ON WAFFLE SLAB WITH DIFFERENT RIB SIZES K. SAKETH*, C. ARUNKUMAR
More informationTechnical Memorandum (Bridges) Rules for the Design and Use of Freyssinet Concrete Hinges in Highway Structures
THE HIGHWAYS AGENCY THE SCOTTISH OFFICE DEVELOPMENT DEPARTMENT THE WELSH OFFICE Y SWYDDFA GYMREIG THE DEPARTMENT OF THE ENVIRONMENT FOR NORTHERN IRELAND Technical Memorandum (Bridges) Rules for the Design
More informationBridge articulation No. 1.04
Bridge articulation Scope This Guidance Note gives advice on the selection of the articulation arrangements, the choice of bearing types and dispositions of bearings, for bridges where relative movement
More information1. BS 5950: Structural use of steelwork in building Part 1: Code of practice for design of simple and continuous construction, BSI, 1990
Bibliography 1. BS 5950: Structural use of steelwork in building Part 1: Code of practice for design of simple and continuous construction, BSI, 1990 2. BS 6399: Loading for buildings Part 1: Code of practice
More informationStructural behaviour and failure mechanisms of concrete monoblock railway sleepers
Structural behaviour and failure mechanisms of concrete monoblock railway sleepers Olli Kerokoski, Antti Nurmikolu and Tommi Rantala Department of Civil Engineering, Tampere University of Technology, P.O.
More informationInternational Journal of Intellectual Advancements and Research in Engineering Computations
www.ijiarec.com ISSN:2348-2079 Volume-5 Issue-1 International Journal of Intellectual Advancements and Research in Engineering Computations Pushover analysis on rc frames with and without shear wall Parishith
More informationVALLIAMMAI ENGINEERING COLLEGE DEPARTMENT OF MECHANICAL ENGINEERING QUESTION BANK CE 6306 - STRENGTH OF MATERIALS UNIT I STRESS STRAIN DEFORMATION OF SOLIDS PART- A (2 Marks) 1. What is Hooke s Law? 2.
More informationPERFORMANCE-BASED DESIGN OF CONCRETE STRUCTURES
PERFORMANCE-BASED DESIGN OF CONCRETE STRUCTURES - JSCE STANDARD SPECIFICATIONS FOR CONCRETE STRUCTURES ON STRUCTURAL PERFORMANCE VERIFICATION - Hiroshi YOKOTA 1 SUMMARY The worldwide trend for structural
More informationEvaluation of Seismic Behaviour of Old Reinforced Concrete Structures Based on Ductility Limit
Evaluation of Seismic Behaviour of Old Reinforced Concrete Structures Based on Ductility Limit T.L Pradeep 1, A. I. Deegala 2, Michelangelo Laterza 3, Michele D Amato 3 1 Department of Civil Engineering
More informationANALYTICAL AND EXPERIMENTAL STUDY ON COMPOSITE FRAMES
ANALYTICAL AND EXPERIMENTAL STUDY ON COMPOSITE FRAMES ARCHANA P1, ANJUGHAP PRIYA R2, SARANYA M3 1PG Student, Dept. of Civil Engineering, Valliammai Engineering College, Chennai, Tamil Nadu 2 Assistant
More informationTEST STUDY ON BASIC STATIC CHARACTERISTICS OF CABLE SUPPORTED BARREL VAULT STRUCTURE
Advanced Steel Construction Vol. 8, No. 2, pp. 199-211 (2012) 199 TEST STUDY ON BASIC STATIC CHARACTERISTICS OF CABLE SUPPORTED BARREL VAULT STRUCTURE Wentao Qiao 1,*, Zhihua Chen 2 and Mingshan Zhao 3
More informationVerification of the reinforced concrete beam model based on the results of a full-scale experimental study
Verification of the reinforced concrete beam model based on the results of a full-scale experimental study Oleg Mkrtychev 1, and Mikhail Andreev 1,* 1 Moscow State University of Civil Engineering, Yaroslavskoe
More informationUNIVERSITY OF BOLTON WESTERN INTERNATIONAL COLLEGE FZE. BEng (HONS) CIVIL ENGINEERING SEMESTER ONE EXAMINATION 2018/2019
OCD030 UNIVERSITY OF BOLTON WESTERN INTERNATIONAL COLLEGE FZE BEng (HONS) CIVIL ENGINEERING SEMESTER ONE EXAMINATION 2018/2019 ADVANCED STRUCTURAL ANALYSIS AND DESIGN MODULE NO: CIE6001 Date: Tuesday 8
More informationUNIVERSITY OF BOLTON SCHOOL OF ENGINEERING. BEng (Hons) CIVIL ENGINEERING
TW7 UNIVERSITY OF BOLTON SCHOOL OF ENGINEERING BEng (Hons) CIVIL ENGINEERING SEMESTER 2 EXAMINATION 2015/2016 ADVANCED STRUCTURAL ANALYSIS & DESIGN MODULE NO. CIE6001 Date: Thursday 19 th May 2016 Time:
More informationDURABILITY AND SERVICEABILITY
DURABILITY AND SERVICEABILITY Introduction of Durability Durability requirements are to ensure that a structure has satisfactory durability and serviceability performance under normal circumstances throughout
More informationTHE BEHAVIOUR OF LIGHTWEIGHT COMPOSITE FLOOR TRUSSES IN FIRE
THE BEHAVIOUR OF LIGHTWEIGHT COMPOSITE FLOOR TRUSSES IN FIRE S.K. Choi, I.W. Burgess Department of Civil and Structural Engineering, University of Sheffield, Sheffield S1 3JD, UK R.J. Plank School of Architecture,
More information