COMPUTERIZED DESIGN OF REINFORCED CONCRETE ELEMENTS TO EUROCODE 2

MOHD ASFAHANI BIN SUKIMAN

UNIVERSITI TEKNOLOGI MALAYSIA

PSZ 19:16 (Pind. 1/97)

UNIVERSITI TEKNOLOGI MALAYSIA

BORANG PENGESAHAN STATUS TESIS

JUDUL: COMPUTERIZED DESIGN OF REINFORCED CONCRETE ELEMENTS TO EUROCODE 2

SESI PENGAJIAN: 2006/2007

Saya MOHD ASFAHANI BIN SUKIMAN (HURUF BESAR)

mengaku membenarkan tesis (PSM/Sarjana/Doktor Falsafah)* ini disimpan di Perpustakaan Universiti Teknologi Malaysia dengan syarat-syarat kegunaan seperti berikut:

1. Tesis adalah hakmilik Universiti Teknologi Malaysia. 2. Perpustakaan Universiti Teknologi Malaysia dibenarkan membuat salinan untuk tujuan pengajian sahaja. 3. Perpustakaan dibenarkan membuat salinan tesis ini sebagai bahan pertukaran antara institusi pengajian tinggi. 4. **Sila tandakan ( )

SULIT (Mengandungi maklumat yang berdarjah keselamatan atau kepentingan Malaysia seperti yang termaktub di dalam AKTA RAHSIA RASMI 1972)

TERHAD (Mengandungi maklumat TERHAD yang telah ditentukan oleh organisasi/badan di mana penyelidikan dijalankan)

TIDAK TERHAD

Disahkan oleh

_______________________________ ________________________________

(TANDATANGAN PENULIS) (TANDATANGAN PENYELIA)

Alamat Tetap: 37, JALAN IKHLAS 9, IR. MOHD SALLEH HJ YASSIN . BANDAR TUN RAZAK (Nama Penyelia) 56000, CHERAS, KUALA LUMPUR

Tarikh: 23 APRIL 2007 Tarikh: 23 APRIL 2007 .

CATATAN: * Potong yang tidak berkenaan. ** Jika tesis ini SULIT atau TERHAD, sila lampirkan surat daripada pihak

berkuasa/organisasi berkenaan dengan menyatakan sekali sebab dan tempoh tesis ini perlu dikelaskan sebagai SULIT atau TERHAD.

Tesis dimaksudkan sebagai tesis bagi Ijazah Doktor Falsafah dan Sarjana

secara penyelidikan, atau disertasi bagi pengajian secara kerja kursus dan penyelidikan, atau Laporan Projek Sarjana Muda (PSM)

I hereby declare that I have read this thesis and in my opinion this thesis is sufficient in terms of scope and quality for the award of the Degree of Bachelor of Civil Engineering.

Signature : ...

Name of Supervisor : IR. MOHD SALLEH HJ YASSIN Date : 23 APRIL 2007

COMPUTERIZED DESIGN OF REINFORCED CONCRETE ELEMENTS TO

EUROCODE 2

MOHD ASFAHANI BIN SUKIMAN

A report submitted in partial fulfillment of the requirements for the award of the degree of

Bachelor of Civil Engineering

Faculty of Civil Engineering Universiti Teknologi Malaysia

April, 2007

REKABENTUK ELEMEN KONKRIT BERTETULANG BERKOMPUTER

BERDASARKAN EUROCODE 2

MOHD ASFAHANI BIN SUKIMAN

Laporan dikemukakan sebagai memenuhi sebahagian daripada syarat penganugerahan

Ijazah Sarjana Muda Kejuruteraan Awam

Fakulti Kejuruteraan Awam Universiti Teknologi Malaysia

April, 2007

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I declare that this research report is the result of my own research except as cited in the references. The research report has not been accepted for any degree and is not concurrently submitted in candidature of any other degree.

Signature : ... Name of Arthur : MOHD ASFAHANI BIN SUKIMAN Date : 23 APRIL 2007

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Special thanks to my loving parents,

En. Sukiman bin Surahman Pn. Rashidah Hanim binti Abdul Hamid

Ive always cherished your expressions of love

over the years .and even more grateful

that ALLAH has given me PARENTS like both of you

to my dear siblings,

and last but not least,

to my beloved Amirah Farhana Mohamad thank you for your support and understanding.

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ACKNOWLEDGEMENT

Right from the start of conducting this thesis, many challenges that I have come through are not without the help of the valuable individuals around me, either people that Ive just met or those who are always with me. I would like to acknowledge these people and give my sincerest appreciation, in particular, to my supervisor, Ir. Mohd Salleh Hj Yassin for his guidance, critics, valuable advice and inspirational encouragement throughout the process of this thesis. Im truly grateful

for the trust and confidence that he has in me to accomplish this thesis to the best of my ability.

I would also like to thank my family, who has given me continual support and encouragement during the duration of my studies away from home. Without them, this humpty dumpty wouldnt be able to put himself back together again after each fall.

Last but not least, my gratitude to my fellow friends and colleagues, who has made my life in UTM a fulfilling and memorable one. Their direct or indirect involvement in this thesis will always be appreciated, thank you for your help and support through thick and thin, hardship and laughter. May our friendship last for as long as we can remember.

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ABSTRACT

The introduction and implementation of the new Eurocodes is a significant event for all construction industries. Eurocode 2: Design of Concrete Structures will affect all concrete design once the current British Standards, BS 8110 for design of reinforced concrete structures has been withdrawn. Thus, this research focuses on the application of these sets of new design codes in the form of spreadsheets from Microsoft Excel for the purpose of analyzing and designing of reinforced concrete elements, mainly beams and slabs. Basically, the procedures in designing these elements require numerous calculations in order to reach the most desired and economical design. Spreadsheet in Microsoft Excel has the capability of solving problems related to equations and formulas in a short time which makes design calculations and procedures easier. Besides that, Microsoft Excel is easily available and also presented in a user-friendly manner. Two softwares have been developed with design procedures based on Eurocode 2, which is the design of concrete beams and slabs. Necessary checking such as deflection and crack control is also calculated by the software which helps to improve the accuracy of the design. The calculation done by the software was compared to manual calculation to ensure the reliability of this software. Results and conclusions show that this software fulfills the research objectives which are to develop a software to aid designers in the transition of using Eurocode 2.

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ABSTRAK

Pengenalan dan perlaksanaan penggunaan kod amalan baru Eurocode 2 adalah sesuatu peristiwa yang nyata dalam bidang kejuruteraan awam dan industri pembinaan. Eurocode 2: Rekabentuk Struktur Konkrit akan mempengaruhi kesemua rekabentuk konkrit apabila kod amalan semasa British Standards, BS 8110 bagi rekabentuk konkrit bertetulang dimansuhkan. Oleh demikian, kajian ini memberi fokus kepada perlaksanaan kod-kod baru ini dalam bentuk spreadsheet perisian Microsoft Excel bagi tujuan menganalisis dan merekabentuk struktur konkrit bertetulang, terutamanya rasuk dan papak. Pada asasnya, prosedur untuk merekabentuk struktur tersebut memerlukan pengiraan berkali-kali bagi mencapai rekabentuk yang ekonomi dan diingini. Spreadsheet dalam Microsoft Excel dalam menyelesaikan masalah berkaitan dengan pengiraan persamaan dan formula dalam masa yang singkat, membuatkan rekabentuk prosedur dapat diselesaikan dengan lebih mudah. Selain itu, Microsoft Excel juga mudah diperolehi dan digunakan. Dua perisian telah dibangunkan berpandukan prosedur rekabentuk dalam Eurocode 2, iaitu rekabentuk rasuk dan papak. Pemeriksaan yang perlu dalam rekabentuk seperti keretakan dan pesongan juga akan dikira oleh perisian ini, justeru membantu meningkatkan ketepatan rekabentuk. Kiraan yang dibuat oleh perisian ini telah dibandingkan dengan pengiraan manual bagi memastikan ketepatannya. Keputusan dan kesimpulan pada akhir kajian dalam membangunkan perisian ini memenuhi objektif kajian, iaitu untuk membangunkan perisian rekabentuk bagi membantu para jurutera dalam proses peralihan kepada penggunaan Eurocode 2.

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TABLE OF CONTENTS

CHAPTER TITLE PAGE

DECLARATION ii DEDICATION iii ACKNOWLEDGEMENT iv ABSTRACT v ABSTRAK vi TABLE OF CONTENTS vii LIST OF TABLES xi LIST OF FIGURES xii LIST OF SYMBOLS xiv LIST OF APPENDICES xvi

1 INTRODUCTION 1 1.1 Research Background 1 1.2 Problem Statement 2 1.3 Research Objectives 2 1.4 Scope of Research 3

1.5 Importance of Research 3

2 LITERATURE REVIEW 5 2.1 Introduction 5 2.2 Eurocode 2 6 2.2.1 Principles of Eurocode 2 7 2.2.2 Aims and Purposes of Eurocode 2 8 2.2.3 Design Life 8

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2.3 Actions on Structures 9 2.4 Combinations of Actions 10 2.4.1 Ultimate Limit State 11 2.4.2 Serviceability Limit State 13 2.5 Load Arrangements 13 2.6 Material Properties 15 2.6.1 Concrete 16 2.6.2 Reinforcing Steel 16 2.7 Durability and Minimum Concrete Cover 17 2.7.1 Minimum Cover for Bond 18 2.7.2 Minimum Cover for Durability 18 2.8 Structural Analysis 21

2.9 Design Procedures for Beam 22 2.9.1 Design for Flexural 22 2.9.2 Vertical Shear 24 2.9.3 Flanged Beams 26 2.9.4 Spacing and Quantity of Reinforcement 27 2.10 Design Procedures for Slab 28 2.10.1 Analysis of One Way and Two Way Slab 28 2.10.2 Design for Shear 29 2.10.3 Spacing and Quantity of Reinforcement 30 2.11 Deflection and Crack Control 31 2.12 Bond and Anchorage 34

3 RESEARCH METHODOLOGY 36 3.1 Introduction 36 3.2 Design Using Microsoft Excel 37 3.3 Flow Chart Establishment 38 3.3.1 Research Flow Chart 38

3.3.2 Flow Charts for Beam Design 39 3.3.3 Flow Charts for Slab Design 42

4 RESULTS AND DISCUSSION 45 4.1 Introduction 45

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4.2 Challenges 45 4.3 Software Development 46 4.4 Data Erroneous 47

4.5 Manual Calculation and Excel Comparison 47 4.6 User Manual 48 4.7 Computerized Design Procedures 53 4.8 Beam Design 54 4.8.1 1 Span Simply Supported Beam 54 4.8.1.1 Analysis of Actions 54 4.8.1.2 Design for Flexural 56 4.8.1.3 Vertical Shear 57 4.8.1.4 Deflection Check 58 4.8.1.5 Crack Control 59 4.8.1.6 Design Results for Beam 60 4.8.2 2 Span Continuous Beam 61 4.8.2.1 Analysis of Actions 61 4.8.2.2 Flexure, Vertical Shear, 63 Deflection, & Crack Control 4.8.3 3 and 4 Span Continuous Beams 64 4.8.3.1 Analysis of Actions 64 4.8.3.2 Flexure, Vertical Shear, 64 Deflection, & Crack Control 4.9 Slab Design 65 4.9.1 Analysis of Actions and Slab Type 65 Determination

4.9.2 Design for Flexural 66 4.9.3 Design for Shear 67 4.9.4 Deflection and Crack Control 68 4.9.5 Design Results for Slab 68 4.10 Software Limitations 70

5 CONCLUSION AND SUGGESTIONS 71 5.1 Conclusion 72 5.2 Suggestions 73

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REFERENCES 74 APPENDICES 75

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LIST OF TABLES

TABLE NO. TITLE PAGE 2.1 Indicative design working life 9 2.2 Selected bulk density of materials (from Eurocode 9 1, Part 1-1) 2.3 Selected imposed loads for buildings 10 2.4 Design values of actions, ultimate limit state 12 persistent and transient design situations 2.5 Design values of actions, derived for UK design, 12 ultimate limit state persistent and transient design situations

2.6 Design values of actions, serviceability limit state 13 2.7 Example design combinations for deflection 13 (quasi-permanent) derived for typical UK reinforced concrete design 2.8 Selected concrete properties based on table 3.1 of 16 Eurocode 2, Part 1-1 2.9 Characteristic tensile strength of reinforcement 17 2.10 Exposure classes 19 2.11 Selected recommendations for normal-weight 20 reinforced concrete quality or combined exposure classes and cover to reinforcement for at least a 50-year intended working life and 20 mm maximum aggregate size.

2.12 Banding moment and shear coefficients for beams 22 2.13 Bending moment and shear coefficients for slabs 29 2.14 Maximum bar size or spacing to limit crack width 34

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LIST OF FIGURES

FIGURE NO. TITLE PAGE 2.1 The Eurocodes 6 2.2 Alternate spans loaded 14 2.3 Adjacent spans loaded 14 2.4 All spans loaded 15 2.5 Simplified rectangular stress block for concrete up 23 to class C50/60 from Eurocode 2 2.6 Strut inclination method 25 2.7 Definition of l0, for calculation of effective flange 26 width 2.8 Effective flange width parameters 26 2.9 Placing of tension reinforcement in flanged cross 27 section Characteristic tensile strength of reinforcement

2.10 Basic span-to-effective-depth ratios Exposure classes 33 3.1 Research flow chart 38

3.2 Beam design procedure 39 3.3 Flexural design for beams 40 3.4 Shear design for beams 41 3.5 Deflection check for beams 41 3.6 Slab design procedure 42 3.7 Flexural design for slabs 43 3.8 Shear design for slabs 44 3.9 Deflection check for slabs 44 4.1 Starting the software 48 4.2 Main Menu Interface 49 4.3 Example of beam selection menu 49

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4.4 Input menu for beams 50 4.5 Input menu for slab 50 4.6 Example of design calculations sheet 51 4.7 Example of design results 51 4.8 Example of output and rough detailing 52 4.9 Determination of b1 and b2 55 4.10 Analysis of actions 56 4.11 Flexural design of beams 57 4.12 Calculation of Shear reinforcements for beams 58 4.13 Deflection checking 59 4.14 Checking crack control 60 4.15 Design Results for beams 61 4.16 Loading arrangements for 2 span beams 62 4.17 Moment distribution for 2 span beams 62 4.18 Shear force diagram 63 4.19 Bending moment diagram 63 4.20 Loading arrangements for 3 & 4 span beams design 65 4.21 Determining type of slab and coefficient analysis 66 4.22 Flexural design of slabs 67 4.23 Shear analysis for slab 67 4.24 Crack control for slab 68 4.25 Design results for slab 69 4.26 Slab output and detailing 69

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LIST OF SYMBOLS

A - Cross sectional area

Ac -

Cross sectional area of concrete

As -

Cross sectional area of reinforcement

As min -

Minimum cross sectional area of reinforcement

As max -

Maximum cross sectional area of reinforcement

Gk - Characteristic permanent action

L - Length

M - Bending moment M

Ed - Design value of the applied internal bending moment

Qk -

Characteristic variable action

V - Shear force

VEd -

Design value of the applied shear force

b - Overall width of a cross-section, or actual flange width in a T or L beam b

w - Width of the web on T or L beams

d - Depth d

eff - Effective depth of a cross section

fcd -

Design value of concrete compressive strength

fck -

Characteristic compressive cylinder strength of concrete at 28 days

fctk -

Characteristic axial tensile strength of concrete

fctm -

Mean value of axial tensile strength of concrete

fyk -

Characteristic yield strength of reinforcement

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fywd -

Design yield of shear reinforcement

h - Height hf - Flange thickness l - Length of span z - Lever arm of internal forces

- Angle ; ratio

c -

Partial factor for concrete

s -

Partial factor for reinforcing or prestressing steel

- Angle

cp -

Compressive stress in the concrete from axial load or

prestressing

- Diameter of a reinforcing bar or of a prestressing duct

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LIST OF APPENDICES

APPENDIX TITLE PAGE

A User Guide and Manual 75 B1 Example of Beam Design 79 B2 Example Calculation of Beam Design 83 C1 Example of Slab Design 93 C2 Example Calculation of Slab Design 96

CHAPTER 1

INTRODUCTION

1.1 Research Background

In this new era of civil engineering structures and technology, more complex and sophisticated design of concrete structures are more common nowadays. It has become more challenging for engineers and designers to fulfill the requirements of their clients. Due to this demands, some improvement has been applied to concrete and are important for timely repair, safety and long-term durability of critical structures such as the development of new codes and standards. Eurocodes are sets of newly developed standards which focus on the above matter.

With the introduction of Eurocode 2 as the new design standard for concrete structures, learning to use it will require time and effort on behalf of the designer. By creating software based on these new codes, it hopes to help the transition from using the BS 8110 to Eurocode 2 more easily.

As the technology keeps on improving on a different level, civil engineers have to use this to their advantage and minimize their workload. The usage of computer technology in civil engineering has becoming more common nowadays. To reduce the time and cost of design, engineers places great reliance by using

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sophisticated software products as the speed of design makes the difference between profits and loss in todays market.

1.2 Problem Statement

Several problems have contributed to the needs of this research and the development of the software. The problems are:

i. Manual and countless calculations could lead to numerous mistakes and delay in design.

ii. Learning to use the new Eurocode 2 will require time and effort. Therefore using programming methods on the new design elements will help designers on the transition to the adaptation of the new code.

iii. Little knowledge and attention of the construction community about the newly developed Eurocodes.

1.3 Research Objectives

In this research, a few objectives have been revised to be a guideline. The objectives of this study are:

i. To develop a user friendly software using Microsoft Excel to simplify and assist in design calculation of concrete structures.

ii. To get a more accurate and economic result in designing without compromising the safety of the structures.

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1.4 Scope of Research

This research focuses on designing concrete structures base on Eurocode 2: Design of concrete structures. It is also to ease the transition from using BS codes to Eurocode 2 by developing software from Microsoft Excel. Thus, in order to achieve this objective, research scopes have to be followed and revised. The research scopes are:

i. Design and analysis is focused only on reinforced concrete beams and slabs including the design process, load arrangements, materials, and structural analysis.

ii. Microsoft Excel as the main platform for analyzing and calculating all the major processes of designing concrete beams and slabs.

iii. Research about the design criteria and considerations based on the approach of Eurocode 2.

iv. To recalculate manually and check the accuracy of the software.

1.5 Importance of Research

The introduction and implementation of the new Eurocodes is a significant event for all construction industries. Eurocode 2: Design of Concrete Structures will affect all concrete design once the current British Standards, BS 8110 for design of reinforced concrete structures has been withdrawn.

When or before Eurocode 2 was introduced in early 2003, most engineers will need to be assured that it can be used as a practical concrete design tool, as well as producing economic results. If they are not assured of this, practices will continue to use BS 8110 in preference to adopting the new codes.

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The importance of this research is to help engineers understand the concepts of Eurocode 2. Through this research, a software, with aid from Microsoft Excel, will be developed which designs concrete structures (beams and slabs) according to the design standards of Eurocode 2. Through this software, users will easily understand the concepts of Eurocode 2 and use it to their advantage on designing concrete beams and slabs of a building with ease.