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Content of Cement on the Durability and Strength of Concrete Exposed to Sodium Sulfate Environment Amin A

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Content of Cement on the Durability and Strength of Concrete Exposed to Sodium Sulfate Environment Amin A University of South Florida Scholar Commons Graduate Theses and Dissertations Graduate School 11-5-2004 Influence of the SO3 Content of Cement on the Durability and Strength of Concrete Exposed to Sodium Sulfate Environment Amin A. Hanhan University of South Florida Follow this and additional works at: https://scholarcommons.usf.edu/etd Part of the American Studies Commons Scholar Commons Citation Hanhan, Amin A., "Influence of the SO3 Content of Cement on the Durability and Strength of Concrete Exposed to Sodium Sulfate Environment" (2004). Graduate Theses and Dissertations. https://scholarcommons.usf.edu/etd/1066 This Thesis is brought to you for free and open access by the Graduate School at Scholar Commons. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. Influence of the SO3 Content of Cement on the Durability and Strength of Concrete Exposed to Sodium Sulfate Environment by Amin A. Hanhan A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Civil Engineering Department of Civil and Environmental Engineering College of Engineering University of South Florida Major Professor: Abla Zayed, Ph.D. Rajan Sen, Ph.D. Ram Pendyala, Ph.D. Date of Approval: November 5th, 2004 Keywords: Sulfur Trioxide, Compressive Strength, Expansion, Gypsum, Sulfate Attack © Copyright 2004, Amin A. Hanhan TABLE OF CONTENTS LIST OF TABLES iii LIST OF FIGURES v LIST OF SYMBOLS AND ABBREVIATIONS ix ABSTRACT xi CHAPTER 1. INTRODUCTION 1 1.1 Objective 1 1.2 Phases in Clinker and Portland Cement 2 1.3 Composition of Portland Cement 4 1.3.1 Compound Composition 4 1.3.2 Impurity Oxides 6 1.3.3 Sources of Sulfates 6 1.4 Hydration of Portland Cement 8 1.5 Review of Previous Research 11 1.5.1 C3A and C4AF Hydration 28 1.5.2 Effect of Alkalis 32 1.5.3 Effects of Temperature 39 CHAPTER 2. EXPERIMENTAL PROCEDURE 40 2.1 Materials 40 2.1.1 Cements 40 2.1.1.1 Oxide Chemical Composition of the Cements 40 2.1.1.2 Bogue Calculations 40 2.1.2 Gypsum 41 2.1.3 Sand 41 2.1.4 Water 41 2.1.5 Sodium Sulfate 41 2.1.6 Fly Ash 41 2.2 Strength and Durability Tests 42 2.2.1 Mortar Cubes 42 2.2.2 Mortar Bars 46 2.3 X-Ray Powder Diffraction Analysis of Mortar Cubes and Bars 49 i CHAPTER 3. RESULTS AND DISCUSSION 50 3.1 Characteristics of the As-Received Cements 50 3.1.1 Cement Fineness 50 3.1.2 Oxide Chemical Composition 51 3.2 Compound Composition 52 3.2.1 Mineralogical Composition According to Bogue Calculations 52 3.2.2 Mineralogical Composition According to Internal Standard Method and Rietveld Refinement Method 53 3.3 Strength and Durability 56 3.3.1 Compressive Strength of Mortar Cubes 56 3.3.2 Expansion of Mortar Bars in Sodium Sulfate Solution 76 3.4 X-Ray Diffraction Analysis of Mortar Cubes 86 3.5 X-Ray Diffraction Analysis of Mortar Bars 89 CHAPTER 4. CONCLUSIONS AND RECOMMENDATIONS 95 REFERENCES 97 ii LIST OF TABLES Table 1. Mix Proportions for the Mortar Cubes Prepared from the As-Received Cements 42 Table 2. Mix Proportions for the Mortar Cubes Prepared from the Cements with 3.0% SO3 Content 44 Table 3. Mix Proportions for the Mortar Cubes Prepared from the Cements with 3.6% SO3 Content 44 Table 4. Mix Proportions for the Mortar Bars Prepared from the Cements With 20% Fly Ash Replacement and 3.6% SO3 Content of the Remaining Cement 47 Table 5. Proportions of Class F Fly Ash, LOI 4.8%, for 20% Replacement of Cement 48 Table 6. Blaine Fineness 50 Table 7. Oxide Chemical Composition of the As-Received Cements 51 Table 8. Mineralogical Composition According to Bogue Calculations 52 Table 9. Mineralogical Composition Based on the Internal Standard Method 53 Table 10. Rietveld Refinement Results for the As-Received Cements 55 Table 11. Relative Intensity Ratios of Ettringite and Gypsum for the 3.0% SO3 Content Mortar Cubes at the Age of 360 Days in Sulfate 86 Table 12. Relative Intensity Ratios of Ettringite and Gypsum for the 3.6% SO3 Content Mortar Cubes at the Age of 360 Days in Sulfate 87 iii Table 13. Relative Intensity Ratios of Ettringite and Gypsum for the 3.0% SO3 Content Mortar Bars at the Age of 480 Days in Sulfate 89 Table 14. Relative Intensity Ratios of Ettringite and Gypsum for the 3.6% SO3 Content Mortar Bars at the Age of 480 Days in Sulfate 90 iv LIST OF FIGURES Figure 1. Compressive Strength verses SO3 Content for C Cement in Lime 57 Figure 2. Compressive Strength verses SO3 Content for C Cement in Sulfate 57 Figure 3. Compressive Strength verses Age for C, C-3.0, and C-3.6 in Lime 58 Figure 4. Compressive Strength verses Age for C, C-3.0, and C-3.6 in Sulfate 58 Figure 5. Compressive Strength verses SO3 Content for Cement D2 in Lime 60 Figure 6. Compressive Strength verses SO3 Content for Cement D2 in Sulfate 60 Figure 7. Compressive Strength verses Age for Cement D2, D2-3.0, and D2-3.6 in Lime 61 Figure 8. Compressive Strength verses Age for Cement D2, D2-3.0, and D2-3.6 in Sulfate 62 Figure 9. Compressive Strength verses SO3 Content for Cement E in Lime 64 Figure 10. Compressive Strength verses SO3 Content for Cement E in Sulfate 64 Figure 11. Compressive Strength verses Age for Cement E, E-3.0, and E-3.6 in Lime 65 Figure 12. Compressive Strength verses Age for Cement E, E-3.0, and E-3.6 in Sulfate 65 v Figure 13. Compressive Strength verses SO3 Content for Cement P in Lime 67 Figure 14. Compressive Strength verses SO3 Content for Cement P in Sulfate 67 Figure 15. Compressive Strength verses Age for Cement P, P-3.0, and P-3.6 in Lime 69 Figure 16. Compressive Strength verses Age for Cement P, P-3.0, and P-3.6 in Sulfate 69 Figure 17. Compressive Strength verses Age for the As-Received Cements in Lime 70 Figure 18. Compressive Strength verses Age for the Cements with 3.0% SO3 Content in Lime 71 Figure 19. Compressive Strength verses Age for the Cements with 3.6% SO3 Content in Lime 71 Figure 20. Compressive Strength verses Age for the As-Received Cements in Sulfate 72 Figure 21. Compressive Strength verses Age for the Cements with 3.0% SO3 Content in Sulfate 73 Figure 22. Compressive Strength verses Age for the Cements with 3.6% SO3 Content in Sulfate 73 Figure 23. Compressive Strength of Doped Cements at 360 Days in Lime and Sulfates 74 Figure 24. Compressive Strength of Doped Cements at 360 Days in Sulfate 75 Figure 25. Expansion of Bars Prepared with the As-Received Cements 76 Figure 26. Expansion verses Age for the C, C-3.0, C-3.6, and C-FA Bars in Sulfate 78 Figure 27. Expansion verses Age for the D2, D2-3.0, D2-3.6, D2-4.0, and D2-FA Bars in Sulfate 79 vi Figure 28. Expansion verses Age for the E, E-3.0, E-3.6, E-4.2, and E-FA Bars in Sulfate 81 Figure 29. Expansion verses Age for P, P-3.0, P-3.6, and P-FA Bars in Sulfate 83 Figure 30. Expansion verses Age for the Cements with 3.0% SO3 Content in Sulfate 84 Figure 31. Expansion verses Age for the Cements with 3.6% SO3 Content in Sulfate 85 Figure 32. Expansion verses Age for the Cements with 20% Replacement by Fly Ash 85 Figure 33. Relative Intensity Ratios of Ettringite and Gypsum for the 3.0% SO3 Content Mortar Cubes at the Age of 360 Days in Sulfate 87 Figure 34. Relative Intensity Ratios of Ettringite and Gypsum for the 3.6% SO3 Content Mortar Cubes at the Age of 360 Days in Sulfate 88 Figure 35. Relative Intensity Ratios of Ettringite and Gypsum for the C-3.0 and C-3.6 Mortar Bars at the Age of 480 Days in Sulfate 90 Figure 36. Relative Intensity Ratios of Ettringite and Gypsum for the D2-3.0 and D2-3.6 Mortar Bars at the Age of 480 Days in Sulfate 91 Figure 37. Relative Intensity Ratios of Ettringite and Gypsum for the E-3.0 and E-3.6 Mortar Bars at the Age of 480 Days in Sulfate 91 Figure 38. Relative Intensity Ratios of Ettringite and Gypsum for the P-3.0 and P-3.6 Mortar Bars at the Age of 480 Days in Sulfate 92 Figure 39. Relative Intensity Ratios of Ettringite and Gypsum for the 3.0% SO3 Content Mortar Bars at the Age of 480 Days in Sulfate 92 vii Figure 40. Relative Intensity Ratios of Ettringite and Gypsum for the 3.6% SO3 Content Mortar Bars at the Age of 480 Days in Sulfate 93 viii LIST OF SYMBOLS AND ABBREVIATIONS ASTM American Society for Testing and Materials SEM Scanning Electron Microscope XRD X-Ray Diffraction QXRD Quantitative X-Ray Diffraction Cement Chemistry Abbreviations A Alumina, Al2O3 C Calcium Oxide, CaO F Ferric Oxide, Fe2O3 H Water, H2O S Silica, SiO2 Ŝ Sulfur Trioxide, SO3 C3A Tricalcium Aluminate, 3CaO.Al2O3 C4AF Tetracalcium Aluminoferrite, 4CaO.Al2O3.Fe2O3 C2S Dicalcium Silicate, 2CaO.SiO2 C3S Tricalcium Silicate, 3CaO.SiO2 CH Calcium Hydroxide, Ca(OH)2 CŜH2 Gypsum, Ca2SO4.2H2O ix CŜH0.5 Bassanite, Ca2SO4.0.5H2O CŜ Anhydrite, Ca2SO4 C-S-H Calcium Silicate Hydrate, nCaO.SiO2.mH2O C6AŜH32 Ettringite, 3CaO.Al2O3.3CaSO4.32H2O C4AŜH12 Monosulfoaluminate, 3CaO.Al2O3.CaSO4.12H2O x INFLUENCE OF THE SO3 CONTENT OF CEMENT ON THE DURABILITY AND STRENGTH OF CONCRETE EXPOSED TO SODIUM SULFATE ENVIRONMENT Amin A.
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