The influence of binder type and cracking on reinforcing steel corrosion in concrete

.................................................................................................... i Acknowledgments .......................................................................................iii List of abbreviations......................................................................................iv CHAPTER 1: INTRODUCTION ..................................................................................................................... 1.1 1.1 PROBLEM DEFINITION ................................................................................................................................ 1.3 1.2 OBJECTIVES ................................................................................................................................................ 1.3 1.3 SCOPE AND LIMITATIONS............................................................................................................................ 1.4 1.4 GENERAL OUTLINE OF THESIS.................................................................................................................... 1.5 1.5 REFERENCES............................................................................................................................................... 1.7 CHAPTER 2: PRINCIPLES OF STEEL CORROSION ............................................................................... 2.1 2.1 CHEMICAL THERMODYNAMICS................................................................................................................... 2.1 2.1.1 Gibbs Free Energy............................................................................................................................. 2.2 2.1.2 Gibbs free energy and chemical potential.......................................................................................... 2.3 2.2 ELECTROCHEMICAL THERMODYNAMICS AND THE NERNST EQUATION ...................................................... 2.4 2.3 POURBAIX DIAGRAMS ................................................................................................................................ 2.7 2.4 IRON OXIDE STABILITY AND PASSIVITY ................................................................................................... 2.10 2.5 KINETICS OF CORROSION REACTIONS....................................................................................................... 2.13 2.5.1 Activation Polarization .................................................................................................................... 2.15 2.5.2 Concentration polarization .............................................................................................................. 2.18 2.5.3 Resistance polarization.................................................................................................................... 2.19 2.6 COMBINED KINETIC HALF-CELL REACTIONS AND THE EVANS DIAGRAM................................................... 2.20 2.7 PASSIVITY AND KINETIC CONSIDERATIONS ............................................................................................... 2.25 2.8 EFFECT OF CHLORIDES.............................................................................................................................. 2.29 2.8.1 Influence of chloride concentration on corrosion process............................................................... 2.32 2.9 EFFECT OF SULPHIDES............................................................................................................................... 2.34 2.10 CHAPTER SUMMARY............................................................................................................................... 2.38 2.11 REFERENCE............................................................................................................................................. 2.40 CHAPTER 3: PORE WATER CHEMISTRY.......................................................3.1 3.1 PORE SOLUTION CHEMISTRY...................................................................................................................... 3.1 3.1.1 Major Anion and Cation Composition of Pore Solution.................................................................... 3.3 3.1.2 Role of sulphides and other minor anions in pore solution chemistry ............................................... 3.6 3.2 EXPERIMENTAL PROCEDURES................................................................................................................... 3.11