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Cement Heat of Hydration and Thermal Control Ahmadreza Sedaghat

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Cement Heat of Hydration and Thermal Control Ahmadreza Sedaghat University of South Florida Scholar Commons Graduate Theses and Dissertations Graduate School 3-22-2016 Cement Heat of Hydration and Thermal Control Ahmadreza Sedaghat Follow this and additional works at: http://scholarcommons.usf.edu/etd Part of the Civil Engineering Commons, and the Materials Science and Engineering Commons Scholar Commons Citation Sedaghat, Ahmadreza, "Cement Heat of Hydration and Thermal Control" (2016). Graduate Theses and Dissertations. http://scholarcommons.usf.edu/etd/6142 This Dissertation 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]. Cement Heat of Hydration and Thermal Control by Ahmadreza Sedaghat A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Department of Civil and Environmental Engineering College of Engineering University of South Florida Major Professor: A. Zayed, Ph.D. Manoj K. Ram, Ph.D. Mahmoood H. Nachabe, Ph.D. Ajit Mujumdar, Ph.D. Abdul Malik, Ph.D. Date of Approval: January 29, 2016 Keywords: Portland Cement, Isothermal Calorimetry, Graphene Nanoplatelet, Statistical Analysis, Thermal Cracking Copyright © 2016, Ahmadreza Sedaghat DEDICATION I would like to dedicate my dissertation to my parents (Aliasghar Sedaghat, Golnar J. Javidan), my beloved wife Rana, my brother Arsalan and my grandmother Ms. Koukab Sanakhan. A special feeling of gratitude to my parents whose words of encouragement and push for tenacity ring in my ears. My brother Arsalan who supported me emotionally and was a strong pier for my parents to lean on while I was far away from home pursuing my education. He is a true brother and I will owe him for the rest of my life. I dedicate this work to my beloved wife Rana Falahat whose unconditional encouragement and support made it possible for me to pursue my PhD degree. ACKNOWLEDGMENTS I am deeply indebted to my PhD adviser Dr. A. Zayed for her fundamental role in guiding and coordination of my PhD research study during these past five years. She has been motivating and encouraging and provided me with the fund to continue my PhD course of study. My gratitude is also extended to my PhD committee members Dr. Nachabe, Dr. Ram, Dr. Mujumdar and Dr. Malik. Also, I would like to thank Dr. Charles Ishee and Dr. Harvey Deford at the State Materials Office of the Florida Department of Transportation. They provided me with access, training and guide to conduct my experiments. I must acknowledge with tremendous and deep thanks to my uncle Hamid Javan Javidan and my aunt Maryam Zahir Emami who sponsored me financially and provided me with a path to pursue my PhD in U.S. Next I’d like to thank my friends, Osama Ali, Andre Bien-Aime, Dan Buidens, Thomas Meagher, Sina Izadi, Mehdi Khodayari, Natallya Shanahan, and Rajeev Kamal who supported me and provided me with assistance during my PhD course of study. Last but not the least I would like to thank Dr. Goswami for providing access to his lab and equipment for conducting the required experiments. TABLE OF CONTENTS LIST OF TABLES ......................................................................................................................... iii LIST OF FIGURES .........................................................................................................................v ABSTRACT .................................................................................................................................. vii CHAPTER 1: INTRODUCTION ....................................................................................................1 1.1 Initial Stage ..................................................................................................................2 1.2 Induction and Acceleration Stages ...............................................................................4 1.3 Deceleration and Steady State Stages ..........................................................................6 1.4 Statement of Objectives .............................................................................................14 1.5 References ..................................................................................................................15 CHAPTER 2: MEASUREMENT AND PREDICTION OF HEAT OF HYDRATION OF PORTLAND CEMENT USING ISOTHERMAL CONDUCTION CALORIMETRY .........19 2.1 Introduction ................................................................................................................19 2.2 Experimental .............................................................................................................22 2.3 Results and Discussion .............................................................................................27 2.3.1 Signal to Maximum Baseline Deviation Ratio ..........................................27 2.3.2 Heat Flow and Heat of Hydration Data from Cement Samples ..................28 2.3.3 Extrapolation of Total Heat After 24 to 84 Hours of Hydration .................29 2.4 Conclusions ................................................................................................................36 2.5 References .................................................................................................................37 CHAPTER 3: PREDICTION OF ONE, THREE AND SEVEN DAY HEAT OF HYDRATION OF PORTLAND CEMENT ...........................................................................39 3.1 Introduction ................................................................................................................39 3.2 Experimental ..............................................................................................................44 3.3 Results and Discussion ..............................................................................................47 3.3.1 X-ray Diffraction and Phase Quantification of Cements (1) Through (4) .................................................................................................47 3.3.2 Particle Size Distribution of As-received and Ground Cements (1) Through (4) .................................................................................................50 3.3.3 Development of Proposed Heat of Hydration Equations ...........................53 3.3.4 Validation of Proposed Heat of Hydration Equations ...............................58 3.3.5 Evaluation of the Equations Predicting the Seven Day HOH Proposed by the Authors of This Paper and Also, Available in the Literature .....................................................................................................60 3.4 Conclusions and Proposed Future Work ...................................................................65 3.5 References .................................................................................................................68 i CHAPTER 4: INVESTIGATION OF PHYSICAL PROPERTIES OF GRAPHENE-CEMENT COMPOSITE FOR STRUCTURAL APPLICATIONS ........................................................72 4.1 Introduction ................................................................................................................72 4.2 Experimental .............................................................................................................75 4.2.1 As-received Materials ................................................................................75 4.2.2 Composite Materials Preparation ...............................................................75 4.2.3 Materials Characterization ..........................................................................75 4.3 Results and Discussion .............................................................................................78 4.3.1 Cement Characterization .............................................................................78 4.3.2 X-ray Diffraction and Rietveld Analysis ....................................................80 4.3.3 Temperature Treatment of Hydrated Graphene- Cement Composites ....................................................................................81 4.3.4 Morphological Properties of Composite Materials in Hydration ...............83 4.3.5 Electrical Conductivity Properties of Composite Materials in Hydration ....................................................................................................83 4.3.6 Thermal Diffusivity Properties of Composite Materials in Hydration ....................................................................................................85 4.4 Conclusions ................................................................................................................88 4.5 References .................................................................................................................89 CHAPTER 5: INVESTIGATION OF THE PHYSICAL PROPERTIES OF GRAPHENE NANOPLATELET CEMENT PASTE MATRIX IN CONCRETE ELEMENTS SUSCEPTIBLE TO CRACKING ...........................................................................................92 5.1 Introduction ................................................................................................................92 5.2 Material and Methods ...............................................................................................96 5.3 Results and Discussion ...........................................................................................100 5.3.1 Evaluation
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