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UNIVERSITI PUTRA MALAYSIA
ACTIVATION AND CHARACTERIZATION OF DUNE SAND AS PARTIAL CEMENT REPLACEMENT FOR CONCRETE
ASIAH ABDULLAH
FS 2012 2
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ACTIVATION AND CHARACTERIZATION OF DUNE SAND AS PARTIAL
CEMENT REPLACEMENT FOR CONCRETE
By
ASIAH ABDULLAH
Thesis Submitted to the School of Graduate Studies, Universiti Putra Malaysia,
in Fulfillment of the Requirements for the Degree of Master of Science
January 2012
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To my precious parents who always give me fabulous love,
spectacular care and support, to my adorable brothers, and
sisters.
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Abstract of the thesis presented to the Senate of Universiti Putra Malaysia in
fulfillment of the requirements for the degree of Master of Science
ACTIVATION AND CHARACTERIZATION OF DUNE SAND AS PARTIAL
CEMENT REPLACEMENT FOR CONCRETE
By
ASIAH ABDULLAH
January 2012
Chairman: Professor Taufiq Yap Yun Hin, PhD
Faculty: Science
Dune sand obtained in the vicinity of Riyadh, Saudi Arabia has been investigated to
be used as partial cement replacement materials for concrete. Physical and chemical
properties of dune sand were evaluated and it was found that it has potential to be
processed and used as partial cement replacement due to the high silica content of
about 93.4%. However, dune sand is inert and chemically inactive under normal
condition. Results show that the strength decreases with the increase of cement
replacement by dune sand under normal condition. Therefore, different methods have
been developed to enhance the reactivity of dune sand. Three ways were used to
improve the pozzolanic reactivity including chemical activation, mechanical
activation and thermal activation. For chemical activation, four inexpensive materials
which are NaCl, Na2SO4, CaSO4·2H2O and CaCl2·2H2O were chosen for this study.
Results showed that the addition of chemical activators did not demonstrate an
obvious effect on the strength development of the cement. In the mechanical
activation, the dune sand with prolonged grinding was investigated to study the effect
of using different particle size on the dune sand reactivity. However, it did not result
in substantial improvements to strength. For thermal activation, two different
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techniques were used which are calcination (heat treatment) and autoclave curing.
The calcination process was done to activate the raw material of dune sand at
temperature ranging from 400oC to 1000°C. Experimental results indicated that the
ultimate strength of cement pastes decreased with increasing calcination temperature.
The autoclave curing increased the pozzolanic activity of dune sand with significant
improvement in strength. The maximum compressive strength was found at 30%
replacement of cement by dune sand. The final products obtained were further
analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM),
differential thermal analysis (DTA) and thermogravimetric analysis (TGA) to
investigate the mechanism that caused the increase in the compressive strength.
Elimination of Ca(OH)2 peaks in the XRD analysis clearly proved that crystalline
SiO2 in dune sand can quickly react with Ca(OH)2 that are formed from cement
hydration to form a new type C-S-H hydrate (tobermorite) which improve the
strength and concrete structure under autoclave curing. The compressive strength of
autoclaved concrete containing 30% dune sand as partial cement replacement
increased by 28% compared to concrete that have been subjected to the standard
curing after 154 days. Free Ca(OH)2 content was reduced from 26% in control paste
under standard curing to about 3% in autoclaved cement paste containing 30% dune
sand as partial cement replacement which experienced a reduction of about 89%.
DTA results are also in good agreement with findings by TGA showing lower
content of free Ca(OH)2 in autoclaved products compared to the standard curing. In
general, SEM investigation revealed that the utilization of concrete containing 30%
dune sand as partial cement replacement subjected to autoclave curing produced
more compact microstructure compared to those cured under normal curing.
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Abstrak tesis yang dikemukakan kepada Senat Universiti Putra Malaysia sebagai
memenuhi keperluan untuk Ijazah Master Sains
PENGAKTIFAN DAN PENCIRIAN DUNE SAND SEBAGAI BAHAN
SEPARA GANTI SIMEN BAGI KONKRIT
Oleh
ASIAH ABDULLAH
Januari 2012
Pengerusi: Profesor Taufiq Yap Yun Hin, PhD
Fakulti: Sains
Dune sand yang didapati dari kawasan Riyadh, Arab Saudi telah dikaji untuk diguna
pakai sebagai bahan separa gantian simen dalam bancuan konkrit. Ciri-ciri fizikal
dan kimia bagi dune sand telah dikaji. Bahan ini telah dikenalpasti mempunyai
potensi untuk diproses serta digunakan sebagai bahan separa gantian untuk simen
kerana mempunyai peratus kandungan silika yang tinggi iaitu sebanyak 93.4%.
Walau bagaimanapun, dalam keadaan biasa, dune sand lengai dan tidak aktif secara
kimia. Keputusan menunjukkan yang kekuatan spesimen semakin berkurangan
dengan peningkatan penggantian ke atas simen oleh dune sand dalam keadaan biasa.
Oleh itu, pelbagai kaedah telah dijalankan bagi meningkatkan kereaktifan dune sand.
Tiga kaedah telah digunakan untuk meningkatkan kereaktifannya termasuklah
pengaktifan secara kimia, pengaktifan secara mekanikal dan pengaktifan secara
terma. Bagi pengaktifan secara kimia, empat bahan kimia dengan kos yang rendah
iaitu NaCl, Na2SO4, CaSO4·2H2O dan CaCl2·2H2O telah dipilih untuk kajian ini.
Keputusan menunjukkan penambahan bahan-bahan kimia ini ke dalam sistem tidak
menunjukkan kesan yang ketara terhadap perkembangan kekuatan simen. Bagi
pengaktifan secara mekanikal, dune sand telah dikisar kepada saiz yang lebih kecil
untuk mengkaji kesan perbezaan saiz zarah terhadap kereaktifan dune sand. Walau
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bagaimanapun, hasilnya juga tidak menunjukkan perkembangan kekuatan simen
yang memberangsangkan. Bagi pengaktifan secara terma, dua teknik telah digunakan
iaitu rawatan suhu (calcination) dan rawatan autoclave. Proses rawatan suhu telah
dijalankan ke atas dune sand bermula dari suhu 400oC ke 1000
oC. Keputusan
menunjukkan kekuatan simen semakin berkurang dengan peningkatan suhu. Namun
begitu, rawatan autoclave telah berjaya meningkatan kereaktifan dune sand
berdasarkan peningkatan kekuatan simen yang telah terhasil. 30% penggantian ke
atas simen oleh dune sand dikenalpasti sebagai peratus yang dapat memberi kekuatan
yang maksimum kepada sampel. Produk akhir yang terhasil untuk sampel terpilih
telah dicirikan dengan menggunakan pembelauan sinar-X (XRD), mikroskop
elektron imbasan (SEM), analisis pembezaan terma (DTA) dan analisis
termogravimetrik (TGA) bagi mengkaji mekanisme yang menyebabkan peningkatan
kekuatan sampel. Kehilangan puncak bagi Ca(OH)2 dalam analisis XRD jelas
menunjukkan bahawa hablur SiO2 di dalam dune sand dapat bertindak balas dengan
Ca(OH)2 yang terhasil dari proses hidrasi simen untk menghasilkan C-S-H jenis baru
(tobermorite) yang dikenalpasti telah meningkatkan kekuatan dan struktur konkrit
melalui rawatan autoclave. Kekuatan bagi konkrit yang mengandungi 30% dune
sand sebagai bahan separa gantian simen dan dikenakan rawatan autoclave telah
meningkat sebanyak 28% berbanding konkrit yang dirawat dalam keadaan biasa.
Kandungan Ca(OH)2 di dalam sampel paste telah berkurang sebanyak 89% iaitu dari
26% bagi paste kawalan yang dirawat dalam keadaan biasa kepada 3% bagi paste
yang mengandungi 30% dune sand sebagai bahan separa gantian simen dan
dikenakan rawatan autoclave. Keputusan DTA juga adalah selari dengan keputusan
TGA di mana menunjukkan kandungan Ca(OH)2 yang rendah bagi produk yang
terhasil dengan rawatan autoclave berbanding rawatan biasa. Secara amnya,
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berdasarkan keputusan SEM, penggunaan 30% dune sand sebagai bahan gantian
untuk simen bagi konkrit yang dikenakan rawatan autoclave telah menghasilkan
struktur mikro yang lebih mampat berbanding konkrit yang dirawat dalam keadaan
biasa.
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ACKNOWLEDGEMENTS
I wish to express my outmost gratitude to Allah subhanahua ta’ala for the strength
and patience He bestowed on me to undertake this research project.
I would like to acknowledge my sincere appreciation to my supervisor, Prof. Dr.
Taufiq Yap Yun Hin for his trust, dedicated supervision, outstanding guidance,
patience and unconditional support throughout the duration of my master’s studies
and thesis project. My special thanks also dedicated to my project leader (co-
supervisor), Prof. Ir. Dr. Mohd. Saleh Jaafar. If not for the generous help and advice
offered by him, this project would have been a much more difficult task to
accomplish.
I would also like to thank Mr. Halim Othman, Mr. Fairuz Ismail and Madam
Khatijah Hassan from the Department of Civil Engineering, Faculty of Engineering
for their support with technical advice, materials and laboratory facilities; also to
Madam Norazlina Shari, Madam Zaidina Md. Daud and other Science Officers in the
Department of Chemistry, Faculty of Science for their assistance in the
characterization works. Not to forget officers in Characterization Lab and Electron
Microscopy Unit, Department of Chemical and Environmental Engineering, Faculty
of Engineering especially Mr. Ismail Abdul Ghani and Mr. Adli Nazri Mohd Kassim
for their help and advice in running SEM and particle size analysis.
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Special thanks are extended to Prof. Dr. Jamaloddin Noorzaei, Mr. Omer Abdalla
Alawad, Ms. Farhana Abang Abdul Rahim, Mr. Lai Fok How, colleagues and friends
for their help, valuable comments and suggestions during the course of this work.
Most especially, I wish to thank my parent and family for their love, never ending
support and encouragement throughout these years.
Last but not least, sincere and great appreciation goes to the Management of the King
Saud University (KSU), Saudi Arabia especially Prof. Dr. Abdurrahman M.
Alhozaimy and Dr. Abdulaziz Al-Negheimish for providing research grant and to the
Management of Universiti Putra Malaysia (UPM) for unfailing support for us to
undertake this first ever joint research between the KSU and UPM. Financial support
from Universiti Teknologi Mara and Ministry of High Education through Young
Lecturer Scheme is gratefully acknowledged.
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I certify that an Examination Committee has met on 10 January 2012 to conduct the
final examination of Asiah Abdullah on her Master of Science thesis entitled
“Activation and Characterization on Dune Sand as Partial Cement Replacement for
Concrete” in accordance with the Universities and University College Act 1971 and
the Constitution of the Universiti Putra Malaysia [P.U.(A) 106] 15 March 1998. The
Committee recommends that the student be awarded the Master of Science.
Members of the Examination Committee were as follows:
Kamaliah Sirat, PhD
Faculty of Science
Universiti Putra Malaysia
(Chairman)
Anuar Kassim, PhD
Professor
Faculty of Science
Universiti Putra Malaysia
(Internal Examiner)
Mansor Hj Ahmad @ Ayob, PhD
Associate Professor
Faculty of Science
Universiti Putra Malaysia
(Internal Examiner)
Yang Farina Abdul Aziz, PhD
Professor
Faculty of Science and Technology
Universiti Kebangsaan Malaysia
(External Examiner)
_________________________
SEOW HENG FONG, PhD
Professor and Deputy Dean
School of Graduate Studies
Universiti Putra Malaysia
Date: 2 March 2012
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This thesis was submitted to the Senate of Universiti Putra Malaysia and has been
accepted as fulfilment of the requirement for the degree of Master of Science. The
members of Supervisory Committee were as follows:
Taufiq Yap Yun Hin, PhD
Professor
Faculty of Science
Universiti Putra Malaysia
(Chairman)
Mohd. Saleh Jaafar, PhD
Professor
Faculty of Engineering
Universiti Putra Malaysia
(Member)
________________________________
BUJANG BIN KIM HUAT, PhD
Professor and Dean
School of Graduate Studies
Universiti Putra Malaysia
Date:
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DECLARATION
I declare that the thesis is my original work except for the quotations and citations
which have been duly acknowledged. I also declare that it has not been previously,
and is not concurrently, submitted for any other degree at Universiti Putra Malaysia
or at any other institution.
ASIAH ABDULLAH
Date: 10 January 2012
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TABLE OF CONTENTS
Page
ABSTRACT iii
ABSTRAK v
ACKNOWLEDGEMENTS viii
APPROVAL x
DECLARATION xii
LIST OF TABLES xvi
LIST OF FIGURES xvii
LIST OF ABBREVIATIONS xxi
CHAPTER
1 INTRODUCTION
1.1 General Introduction to Portland Cement 1
1.2 The Application of Portland Cement in Construction Industries 2
1.3 Pozzolanic Materials 3
1.3.1 Natural Pozzolanic Materials 4
1.3.2 Artificial Pozzolanis Materials 5
1.4 Problem Statements 6
1.5 Scope and Research Objectives 7
2 LITERATURE REVIEW
2.1 Manufacture of Portland Cement 9
2.1.1 Preparation of Raw Mixture 9
2.1.2 Formation of the Clinker 10
2.1.3 Production of the Cement 11
2.2 Chemical Composition of Portland Cement 12
2.2.1 Alite 15
2.2.2 Belite 15
2.2.3 Aluminate 17
2.2.4 Ferrite 17
2.3 Portland Cement Hydration 17
2.3.1 Hydration of Aluminates 19
2.3.2 Hydration of Silicates 23
2.4 Pozzolanic Reaction 26
2.5 Supplementary Cementitious Materials 28
2.5.1 Silica Fume 28
2.5.2 Fly Ash 30
2.5.3 Ground Granulated Blast Furnace Slag 32
2.6 Dune Sand 33
2.6.1 Properties of Dune Sand 34
2.6.2 Application of Dune Sand 34
2.7 Activation Method 35
2.7.1 Mechanical Activation 35
2.7.2 Thermal Activation 37
2.7.2.1 Calcination 37
2.7.2.2 Elevated Temperature Curing 39
2.7.3 Chemical Activation 42
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2.7.3.1 Alkali Activation 43
2.7.3.2 Sulfate Activation 45
2.7.3.3 Other Type of Activation 46
3 MATERIALS AND METHODS
3.1 Materials 48
3.2 Preparation of Paste 49
3.3 Activation of Dune Sand as Partial Cement Replacement 51
3.3.1 Thermal Activation 52
3.3.1.1 Autoclave Curing 52
3.3.1.2 Calcination 53
3.3.2 Chemical Activation 55
3.3.3 Mechanical Activation 56
3.4 Preparation of Mortar and Concrete 57
3.5 Sample Characterization 58
3.5.1 Chemical Analysis 58
3.5.1.1 X-Ray Fluorescence Analysis 58
3.5.1.2 Energy Dispersive X-Ray 59
3.5.2 BET Surface Area Measurements 60
3.5.3 Particle Size Analysis 61
3.5.4 Compressive Strength 62
3.5.5 X-Ray Diffraction Analysis 63
3.5.6 Scanning Electron Microscope 64
3.5.7 Thermal Analysis 65
3.5.7.1 Thermogravimetric Analysis 65
3.5.7.2 Differential Thermal Analysis 66
4 RESULTS AND DISCUSSION
4.1 Characterization of raw materials 68
4.1.1 Chemical Analysis, BET Surface Area Measurements and
Particle Size Analysis
6
68
4.1.2 Phase Identification Using Powder XRD Technique 70
4.1.3 Scanning Electron Microscope 71
4.2 Effect of Cement Replacement by Dune Sand at Standard
Condition
72
4.2.1 Compressive Strength 72
4.2.2 Phase Identification Using Powder XRD Technique 74
4.2.3 Scanning Electron Microscope 76
4.2.4 Energy Dispersive X-Ray 78
4.2.5 Thermal Analysis 81
4.2.5.1 Thermogravimetric Analysis 81
4.2.5.2 Differential Thermal Analysis 84
4.3 Activation of Dune Sand as Partial Cement Replacement 86
4.3.1 Influence of Thermal Activation on Reactivity of Dune
Sand
86
4.3.1.1 Autoclave Curing 86
4.3.1.2 Calcination 90
4.3.2 Effect of Chemical Activators on the Dune Sand
Reactivity
94
4.3.3 Influence of Mechanical Activation on the Reactivity of 98
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Dune Sand
4.4 Characterization of Activated Hardened Cement Pastes 101
4.4.1 Summary of Effects on Strength 101
4.4.2 Phase Identification Using Powder XRD Technique 102
4.4.3 Scanning Electron Microscope 105
4.4.4 Energy Dispersive X-ray 110
4.4.5 Thermal Analysis 114
4.4.5.1 Thermogravimetric Analysis 114
4.4.5.2 Differential Thermal Analysis 118
5 CONCLUSION AND RECOMMENDATIONS
5.1 Conclusion 120
5.2 Recommendations 123
REFERENCES 124
APPENDICES 132
BIODATA OF STUDENT 151
LIST OF PUBLICATIONS 152