EFFECT OF SQUARE HOLLOW SECTION
ON THE STRENGTH OF FOAMED CONCRETE
BEAM WITH PROCESSED SPENT
BLEACHING EARTH AS PARTIAL
REPLACEMENT OF CEMENT
LEE SENG AIK
B. ENG(HONS.) CIVIL ENGINEERING
SUPERVISOR’S DECLARATION
I hereby declare that I have checked this thesis and in my opinion, this thesis is adequate in terms of scope and quality for the award of the Bachelor Degree of Civil Engineering
_______________________________ (Supervisor’s Signature)
Full Name : Pn. Rokiah Binti Othman Position : Lecturer
STUDENT’S DECLARATION
I hereby declare that the work in this thesis is based on my original work except for quotations and citations which have been duly acknowledged. I also declare that it has not been previously or concurrently submitted for any other degree at Universiti Malaysia Pahang or any other institutions.
_______________________________ (Student’s Signature)
Full Name : LEE SENG AIK ID Number : AA 14221 Date : 5 June 2018
EFFECT OF SQUARE HOLLOW SECTION ON THE STRENGTH OF FOAMED CONCRETE BEAM WITH PROCESSED SPENT BLEACHING EARTH AS
PARTIAL REPLACEMENT OF CEMENT
LEE SENG AIK
Thesis submitted in fulfillment of the requirements for the award of the
Bachelor Degree in Civil Engineering
Faculty of Civil Engineering and Earth Resources UNIVERSITI MALAYSIA PAHANG
ACKNOWLEDGEMENTS
A very great gratitude and appreciation expressed to all those who make a part to the successful cease of this project with title “Effect of square hollow section on the strength of foamed concrete beam with processed spent bleaching earth as partial replacement of cement” which involved either directly or indirectly.
First and foremost, I need to thank to my supervisor, Pn. Rokiah Binti Othman for her support, helps, encouragement and useful guidance which I need the most. I would like to give special thanks to her for having trust and believe on me to finish this project excellently.
I also want to thanks my entire friends who always at my side during this Final Year Project for their ideas and support about the project and as well as helping me in completing it.
Finally, to my beloved family, which supports me from the times, giving motivation, advices and finance support so that I can finish doing this project.
ABSTRAK
Rasuk berongga diperkenalkan untuk mengurangkan kos projek pembinaan serta penggunaan bahan dan formwork. Processed Spent Bleaching Earth (PSBE) adalah SBE yang telah dirawat dan boleh digunakan sebagai pengganti sebahagian untuk simen dalam konkrit berbuih disebabkan oleh kesan pozzolanicnya. Kepekatan konkrit berbuih direka untuk mendapatkan ketumpatan 1600 kg/m³. Objektif kajian ini adalah untuk menentukan beban maksimum rasuk lenturan, pesongan rasuk lenturan dan mod kegagalan rasuk lenturan dengan menggunakan lenturan ujian empat titik. Empat jenis balok telah disediakan iaitu balok FC dikawal sebagai balok pepejal (Beam 1) tanpa bahagian berongga, balok berongga (Beam 2) dengan saiz pembukaan (50mm x 50mm), balok berongga (Beam 3) dengan saiz pembukaan (60mm x 60mm), dan rasuk berongga (Beam 4) dengan saiz pembukaan (70mm x 70mm). Kesemua rasuk itu dipancarkan dengan 30% PSBE sebagai pengganti simen separa. Setiap jenis rasuk disediakan untuk 3 unit rasuk (150mm x 200mm x 1500mm) untuk mencari nilai purata beban maksimum dan pesongan. 4 unit Linear Variable Displacement Transducer (LVDT) digunakan untuk mengukur pesongan rasuk. Corak retak bagi rasuk diperhatikan sepanjang eksperimen dan retak kemudian dianalisis dengan sewajarnya. Dari hasil ujikaji, antara saiz bahagian berongga, Beam 2 menghasilkan beban maksimum yang lebih tinggi dengan 3.94 kN, kekuatan lenturan dengan 0.79 N/mm2 dan pesongan dengan 0.30mm. Hasil kajian menunjukkan kekuatan lenturan rasuk menurun ke tahap tertentu sebanyak 12.7%, 37.3%, dan 51.1% bagi Beam 2, Beam 3, dan Beam 4. Selain itu, hasil untuk pesongan menunjukkan bahawa Beam 2, Beam 3, dan Beam 4 dibelokkan kurang berbanding Beam 1 dengan penurunan masing-masing 9.09%, 17.27% dan 25.76%. Kekuatan lenturan rasuk bergantung kepada momen inersia kedua manakala momen inersia kedua bergantung pada kawasan permukaan balok. Beban maksimum balok dengan bahagian berongga berkurang disebabkan oleh dimensi yang semakin meningkat pada bahagian berongga. Oleh sebab rasuk tidak diperkuat, rasuk-rasuk gagal tanpa sebarang keretakan kecil. Retakan menegak dipanggil retak utama. Oleh itu, kekuatan lenturan dan pesongan seksyen berongga segi empat semakin berkurangan apabila saiz rongga semakin meningkat.
ABSTRACT
Hollow beam is introduced to reduce the cost of the construction project by reducing the use of materials and formworks. Processed Spent Bleaching Earth (PSBE) is the SBE that has been treated and can be used as a partial replacement for cement in the foamed concrete due to its pozzolanic effect. Density of foamed concrete was designed to get 1600 kg/m³ density. The objective of the study is to determine the maximum load of the flexural beam, the deflection of the flexural beam, and the mode of failure of the flexural beam by using 4 point bending test. Four types of beams were prepared which namely controlled FC beam as known as solid beam (Beam 1) without the hollow section, hollow beam (Beam 2) with the opening size of (50mm x 50mm), hollow beam (Beam 3) with the opening size of (60mm x 60mm), and hollow beam (Beam 4) with the opening size of (70mm x 70mm). All the beams were casted with 30% of PSBE as a partial cement replacement. Each type of the beams were prepared for 3 units of beams (150mm x 200mm x 1500mm) to find the average value of maximum load and deflection. The 4 units of Linear Variable Displacement Transducer (LVDT) were used to measure the deflection of the beams. The crack pattern of beams were observed throughout the experiment and the cracking were then analysed accordingly. From the experimental result, in most of the size of hollow section, Beam 2 produced greater maximum load with 3.94 kN, flexural strength with 0.79 N/mm2 and deflection with 0.30mm. The result showed that the flexural strength of the beams decreased to certain degree of percentage of 12.7%, 37.3% and 51.1% for Beam 2, Beam 3 and Beam 4 respectively. Also, result for deflection showed that Beam 2, Beam 3 and Beam 4 deflected less compared to Beam 1 with decrement of 9.09%, 17.27%, and 25.76% respectively. The flexural strength of the beams depends on the second moment of inertia while second moment of inertia depends on the surface area of the beams. The maximum loading of beam with hollow section decreased due to the increasing dimension of hollow section. Since the beams were un-reinforced, therefore, they failed without any appearance of tiny crack. The vertical crack was called ultimate crack. Hence, the flexural strength and deflection of square hollow section decreased as the size of hollow increased.
TABLE OF CONTENT DECLARATION TITLE PAGE ACKNOWLEDGEMENTS ii ABSTRAK iii ABSTRACT iv TABLE OF CONTENT v
LIST OF TABLES viii
LIST OF FIGURES ix LIST OF SYMBOLS x LIST OF ABBREVIATIONS xi CHAPTER 1 INTRODUCTION 1 1.1 Background of Study 1 1.2 Problem Statement 2 1.3 Objectives 3 1.4 Scope of Study 3 1.5 Significance of Study 3
CHAPTER 2 LITERATURE REVIEW 5
2.1 Introduction 5
2.2 Foamed Concrete 5
2.2.1 Application of Foamed Concrete 6
2.3.1 Cement 6
2.3.2 Sand 7
2.3.3 Water 7
2.3.4 Foaming Agent 8
2.4 Effect of Pozzolanic Material 8
2.5 Processed Spent Bleaching Earth 9 2.5.1 Spent Bleaching Earth (SBE) 10
2.5.2 Processed Spent Bleaching Earth (PSBE) 10
2.6 Compressive Strength 11 2.7 Hollow Beam 12 2.8 Bending 12 2.9 Deflection 13 2.10 Mode of Failure 14 2.11 Bending Test 14 CHAPTER 3 METHODOLOGY 15 3.1 Introduction 15 3.2 Research Planning 16 3.3 Specimen Preparation 17 3.3.1 Formwork Preparation 17
3.3.2 Ordinary Portland Cement 19
3.3.3 Silica Sand 20
3.3.4 Protein Foaming Agent 20 3.3.5 Processed Spent Bleaching Earth (PSBE) 21
3.3.6 Water 22
3.5 Casting, Moulding and Unmoulding of the Specimens 23
3.6 Curing Process 24
3.7 Painting 25
3.8 Testing Method 25
3.8.1 Four Point Bending Test 25
CHAPTER 4 RESULTS AND DISCUSSION 27
4.1 Introduction 27
4.2 Flexural Strength 27
4.3 Deflection Profile 29
4.4 Crack Pattern 37
CHAPTER 5 CONCLUSION AND RECOMMENDATIONS 38
5.1 Introduction 38
5.2 Conclusion 38
5.3 Recommendations 39
REFERENCES 40
APPENDIX A CALCULATION (FLEXURAL STRENGTH) 44
LIST OF TABLES
Table 2.1 Properties of SBE and PSBE 11 Table 3.1 Mix Proportion of foamed concrete 22 Table 4.1 Maximum loading and Flexural Strength of Beams 28 Table 4.2 Deflection Data for Beam 1 30 Table 4.3 Deflection Data for Beam 2 30 Table 4.4 Deflection Data for Beam 3 31 Table 4.5 Deflection Data for Beam 4 31 Table 4.6 Deflection Profile Comparison 36 Table 4.7 Cracking Pattern of Beams 37
LIST OF FIGURES
Figure 3.1 Research Experimental Works Flow 16 Figure 3.2 Preparation of Formwork 18 Figure 3.3 Square Hollow Section Formwork 18 Figure 3.4 Ordinary Portland Cement ‘Orang Kuat’ 19
Figure 3.5 Silica Sand 20
Figure 3.6 Protein Foaming Agent 21 Figure 3.7 Processed Spent Bleaching Earth 22 Figure 3.8 Casting of the Specimen 23
Figure 3.9 Curing Process 24
Figure 3.10 Painting of the Beams 25 Figure 3.11 Testing Set Up of the Beam 26
Figure 3.12 Position of LVDT 26
Figure 4.1 Maximum Loading and Flexural Strength of Beams 28 Figure 4.2 Relationship of Force against Deflection for Beam 1 32 Figure 4.3 Relationship of Force against Deflection for Beam 2 32 Figure 4.4 Relationship of Force against Deflection for Beam 3 33 Figure 4.5 Relationship of Force against Deflection for Beam 4 33 Figure 4.6 Deflection Profile for Beam 1 34 Figure 4.7 Deflection Profile for Beam 2 34 Figure 4.8 Deflection Profile for Beam 3 35 Figure 4.9 Deflection Profile for Beam 4 35
LIST OF SYMBOLS % σ δ Percentage Flexural Strength Deflection
LIST OF ABBREVIATIONS ASTM C-H CIDB C-S-H GHG IBS
American Society for Testing and Materials Calcium Hydroxide
Construction Industry Development Board Calcium Silica Hydrate
Greenhouse Gases
Industrialised Building System LVDT
NGOs PSBE SBE
linear variable displacement transducer Non-Governmental Organizations Processed Spent Bleaching Earth Spent Bleaching Earth
CHAPTER 1
INTRODUCTION
1.1 Background of Study
Over the past several decades, Malaysia is still unfamiliar with the usage of Industrialised Building System (IBS) although it is implemented in early 1960’s. The practise of IBS has been widely promoted by Construction Industry Development Board (CIDB) in Malaysia Construction Industry since 1998. It is widely used when Cabinet of Ministers endorsed IBS Strategic Plan as the blueprint for the total industrialisation of the construction sector. The objectives of using IBS is to slowly decrease the usage of foreign labours, improve quality of project and increase productivity (Mohamad, Zawawi, & Nekooie, 2009). IBS also simplified construction work by reducing the time and as well reducing the cost of the construction.
For the construction of first floor beam, hollow beam is introduced to reduce the cost of the construction project by reducing the use of formwork when casting the secondary beam. As the hollow beam with reduced weight can be supported by lesser formwork during the process, lesser formwork is required to support the structure until the end of curing system. On the other hand, improper supervision and control of formwork systems can possibly affect the construction schedule and consequently impact the total cost of construction (Mansuri et al., 2017). Lightweight foamed concrete has a lot of advantages. Besides it is easily made, it is also lightweight which is easy to handle and also lightweight foamed concrete is a good heat insulator (Jones & McCarthy, 2005). The idea of making hollow beam is the same as the introduction of concrete hollow-core panels which widely used for parking structures, bridges and concrete buildings (Baran, 2015). By referring to the law of second moment of inertia, there is an effect on the shear resistance and bending moment of beam when the surface area is
reduced. Hence, this study is to investigate the effect of square hollow section on the strength of foamed concrete beam with processed spent bleaching earth as a partial replacement of cement.
1.2 Problem Statement
Cement is the basic element in construction field. Cement binds concrete particles tightly. Cement is mass-produced for construction purposes. Cement industry is also an energy intensive industry which contributes for greenhouse gases (GHG), CO2, and other
gases emission, NOx and SOx. About 6-8% of carbon production is responsible to cement
industry and around 12-15% of total industrial energy consumed by cement industry (Ali, Saidur, & Hossain, 2011).
Spent bleaching earth (SBE) is a waste material which is derived from the refining process of crude edible oil. The past reports showed that Malaysia palm oil mills produce a significant sum of SBE yearly as a by-product of manufacturing process (Tan, Ahmad, & Hameed, 2009). Due to the huge amount produced each year, SBE is hard to manage because of the lack of technique to recover it (Krzyśko-Łupicka et al., 2014).
Formwork is actually cost a lot in a construction project. Formwork can possibly account for as much as 15% of the total construction cost and 33% of the cost of the concrete structure (Ko, Wang, & Kuo, 2011). The reduction of beam weight can definitely decrease the use of formwork to save the overall cost of the project.
1.3 Objectives
The purpose of this study is to investigate the effect of square hollow section on the strength of foamed concrete beam with processed spent bleaching earth as a partial replacement of cement and the objectives are shown as below:
i. To determine the maximum load of the flexural beam by using four point bending test.
ii. To determine the deflection of the flexural beam. iii. To determine the mode of failure of the flexural beam. 1.4 Scope of Study
In this study, the experiments were conducted in small scale laboratory test basis. American Society of Testing Material (ASTM) was used as reference standards for the laboratory tests involved in this study. To obtain the maximum load, deflection and mode of failure of the solid beam and hollow beam, four point bending test was conducted. Through this study, we worked on determining the maximum load, deflection and mode of failure of the flexural beam by using four point bending test. All the solid beam and hollow beam were tested to compare the maximum load that applied on the beams. The deflection of beams were determined and the mode of failure were identified. Therefore, in the end of this study, the feasibility of using hollow beam in reducing the cost and formwork used were verified.
1.5 Significance of Study
Government and NGOs are generally promote the implementation of sustainability issue in construction field and the construction industry is working hard to exercise it in their projects. By following the concept, both the social responsibility and economic growth were satisfied by construction industry to protect the environment. To adopt the usage of construction wastes in other construction activities, which will not only reduce the weight of beam, but also reduce the cost of construction by reducing the use of formwork, it will also reduce the waste disposal rate to landfills significantly, and it can be interpreted as an effort in preserving the environment. Recycling construction waste materials to be used in construction activities will also minimize the exploitation
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