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TABLE OF CONTENTS

CHAPTER NO. TITLE PAGE NO.

ABSTRACT iii

LIST OF TABLES xvii

LIST OF FIGURES xix

LIST OF SYMBOLS AND ABBREVIATIONS xxvii

1 INTRODUCTION 1

1.1 GENERAL 1

1.2 OBJECTIVES AND SCOPE OF RESEARCH 4

1.3 SCOPE OF THE WORK 4

2 REVIEW OF LITERATURE 7

2.1 GENERAL 7

2.2 HIGH STRENGTH CONCRETE 8

2.3 HIGH PERFORMANCE CONCRETE 8

2.4 CORROSION 9

2.4.1 Effect of Chloride Ingress in Concrete 13 2.4.2 Mode and Mechanisms of Chloride Ion

Ingress in Concrete 13

2.5 IMPROVEMENT OF CONCRETE DURABILITY 14

2.5.1 Effect of Concrete Cover on Durability 14 2.5.2 Effect of Cement Replacement

Materials on concrete Durability 15 2.5.3 Effect of Cement Type on Concrete

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2.5.4 Effect of Aggregate Properties on

Concrete Durability 16

2.5.5 Importance of Water Binder Ratio for a

Durable Concrete 17

2.5.6 Importance of Concrete Mix 18

2.5.7 Effect of Curing Methods 18

2.5.8 Effect of Concrete Cover Thickness on

Corrosion Initiation Period 19

2.6 CONCRETE DURABILITY TEST METHODS 20 2.6.1 Test Methods for Determination of

Durability Properties 21 2.6.2 Steady State and Non Steady State

Chloride Profile 22

2.6.3 Durability Test Parameters 23

2.6.4 Effect of Test Duration 23

2.6.5 Effect of Accelerating Voltage on

Chloride Profile 23

2.6.6 Temperature Variations During the

Test Period 23

2.6.7 Chloride Profile and Chloride Bindings

During the Test Period 24

2.6.8 Concrete Diffusion Co-efficients 25 2.6.9 Diffusion Co-efficient from Profile Method

and the Migration Co-efficient from

Colorimetric Method 26

2.6.10 Diffusion Co-efficient Based on RCPT 27 2.6.11 Initiation Period Based on Diffusion

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2.6.12 Corrosion Initiation Period Based on

Chloride Diffusion Co-efficient 29 2.7 RELATIONSHIP BETWEEN CHLORIDE

DIFFUSION RATE AND CHARGE PASSED

RATE 30

2.7.1 Model for Concrete Cover Cracking due to Rebar Corrosion in RCC Structures 31 2.7.2 Reinforcement Corrosion in Concrete

Structures, its Monitoring and Service

Life Prediction 32

2.7.3 Effect of Chloride Binding on Service Life

Predictions 33

2.7.4 Critical Review about Service Life Concepts of Reinforced Concrete

Structures 34

2.8 CONCLUDING REMARKS 35

3 MATERIALS AND METHODS 36

3.1 MATERIALS 36

3.2 EXPERIMENTAL SETUP 43

3.2.1 Diffusion Setup 44

3.2.2 Rapid Chloride Permeability Test Setup 47

3.2.3 Concrete Resistivity Test 48

3.2.4 Water Permeability Test 50

3.2.5 Polarization test 51

3.3 SPECIMENS DETAILS AND EXPERIMENTAL

PROCEDURE 54

3.3.1 Casting and Curing Methods of Concrete Specimens 54

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3.3.2 Preparation of Specimen for Diffusion

and RCPT Tests 54

3.3.3 Preparation of Specimen for Chloride

Diffusion and RCPT Tests 56

3.3.4 Preparation of Specimen for Polarization

Test 57

3.3.5 Specimen Details for Studying the Effect of Cover Thickness under

Accelerated Corrosion Test 60

3.3.6 Specimens Preparation with Concrete

Surface Coatings 61

3.3.7 Application of Coatings on Specimens 61

3.4 EXPERIMENTAL METHODS 64

3.4.1 Diffusion Test 64

3.4.2 Rapid Chloride Permeability Test 66

3.4.3 Concrete Resistivity Test 67

3.4.4 Polarization Test 68

3.4.5 Depth of Chloride Penetration in

Concretes at Marine Environment. 71

3.5 SUMMARY 72

4 RESULTS AND DISCUSSION 73

4.1 GENERAL 73

4.2 DIFFUSION TEST VALUES 73

4.2.1 Chloride Profile 73

4.2.2 Effect of Concrete Grades on

Chloride Diffusion 75

4.2.3 Effect of Fly Ash on Chloride Diffusion

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4.2.4 Effect of Ground Granulated Blast Furnace Slag (GGBS) on Chloride Diffusion in Different Grades of

Concrete 78

4.2.5 Effect of Corrosion Inhibitors (CI) on Chloride Diffusion in M40 Grade

Concrete 79

4.2.5.1 Compressive Strength 79

4.2.5.2 Flexural Strength 82

4.2.5.3 Split Tensile Strength 84 4.2.6 Effect of Corrosion Inhibitors on

Chloride Diffusion 87

4.2.7 General Observations of Chloride Diffusion Values in Various

Concrete Types 90

4.3 RAPID CHLORIDE ION PENETRATION

TEST VALUES 90

4.3.1 Effect of Concrete Grades on RCPT 90 4.3.2 Effect of Fly Ash in Concretes of

Different Grades on RCPT 91

4.3.3 Effect of Ground Granulated Blast Furnace Slag (GGBS) in Concretes of

Different Grades on RCPT 92 4.3.4 Effect of Corrosion Inhibitors (CI) in

Concretes of Different Grades on RCPT 93 4.3.5 General Observations of RCPT Values in

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4.4 CONCRETE RESISTIVITY TEST VALUES 96 4.4.1 Effect of Concrete Grades on Resistivity 96 4.4.2 Effect of Fly Ash on Resistivity in

Different Grades of Concretes 96 4.4.3 Effect of Ground Granulated Blast

Furnace Slag (GGBS) on Resistivity in

Different Grades of Concretes 98 4.4.4 Effect of Corrosion Inhibitors (CI) on

Resistivity in Different Grades of

Concretes 99 4.4.5 General Observations of Resistivity

Values in Different Concrete Types 102

4.5 WATER PERMEABILITY TEST VALUES 102

4.5.1 Effect of Concrete Grades on

Water Permeability 102

4.5.2 Effect of Fly Ash on Water Permeability in Different Grades of Concretes 103 4.5.3 Effect of Ground Granulated Blast

Furnace Slag (GGBS) on Water Permeability in Different Grades

of Concretes 104

4.5.4 Effect of Corrosion Inhibitors on

Water Permeability 105

4.5.5 General Observations of Water Permeability Values in Different

Types of Concrete 108

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4.6.1 Effect of Concrete Grades on Re-bar

Corrosion 108

4.6.2 Effect of Fly Ash on Re-bar Corrosion

in Different Grades of Concrete 110 4.6.3 Effect of Ground Granulated Blast

Furnace Slag (GGBS) on Re-bar

Corrosion in Different Grades of Concrete 111 4.6.4 Effect of Corrosion Inhibitors in

Concrete on Rebar Corrosion 112

4.6.5 Effect of Concrete Surface Coatings on

Corrosion Initiation Period 115

4.6.6 Effect of Concrete Cover Thickness and

Grades on Corrosion Initiation Time 118 4.6.7 Effect of Fly ash, Cover Thickness and

Grades of Concrete on Corrosion

Initiation Time 120

4.6.8 Effect of Ground Granulated Blast Furnace Slag (GGBS), Cover Thickness and Grades of Concrete on Corrosion

Initiation Time 121

4.6.9 Effect of Corrosion Inhibitor, Cover Thickness and Grades of

Concrete on Corrosion Initiation Time 123 4.7 DEPTH OF CHLORIDE ION PENETRATION

IN DEFFERENT GRADES OF CONCRETE AT MARINE ENVIRONMENT 124

4.8 SUMMARY 126

5.0 RELATIONSHIP BETWEEN DURABILITY

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5.1 GENERAL 130 5.2 CONSTITUTIONAL RELATIONSHIP

BETWEEN RCPT AND CHLORIDE

DIFFUSION 130

5.3 CONSTITUTIONAL RELATIONSHIP

BETWEEN RESISTIVITY AND RCPT 131

5.4 CONSTITUTIONAL RELATIONSHIP

BETWEEN WATER PERMEABILITY

AND RCPT 132

5.5 CONSTITUTIONAL RELATIONSHIP

BETWEEN WATER PERMEABILITY

AND RESISTIVITY 133

5.6 CONSTITUTIONAL RELATIONSHIP

BETWEEN CORROSION INITIATION TIME AND RCPT WITH VARIOUS

COVER THICKNESS 134

5.7 CONSTITUTIONAL RELATIONSHIP

BETWEEN CORROSION INITIATION

TIME AND RESISTIVITY 134

5.8 SERVICE LIFE ESTIMATION BASED ON

CHLORIDE DIFFUSION CO-EFFICIENT 135

5.9 SUMMARY 140

6 MATHEMATICAL MODELLING FOR

SERVICE LIFE ESTIMATION 141

6.1 GENERAL 141

5.2 SOFTWARE HARDWARE REQUIREMENTS

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6.2.1 Hardware Requirements 142

6.2.2 Software Requirements 142

6.3 INPUT PARAMETERS REQUIRED FOR

MODELLING TO ESTIMATE SERVICE

LIFE OF RCC STRUCTURE 142

6.4 PREDICTING THE ACTUAL CORROSION

INITIATION TIME 144

6.5 ESTIMATION OF PROPAGATION PERIOD

AND SERVICE LIFE 145

6.6 EFFECT OF STEEL TYPES ON SERVICE

LIFE 145

6.7 EFFECT OF ENVIRONMENT ON SERVICE

LIFE 145

6.8 DEVELOPEMENT OF SERVICE LIFE MODEL 146

6.9 SYSTEM FLOW DIAGRAM 148

6.10 DATA FLOW DIAGRAM 149

6.10.1 Single Input Module 149

6.10.2 Double Input Module 150

6.10.3 Triple Input Module 151

6.10.4 Four Input Module 152

6.11 CONSTRUCTION OF INPUT TYPES IN

THE MODULES 153

6.12 USER MANUAL 156

6.12.1 Service Life Estimation Model 156 6.12.2 Display Pattern and Operation of

Single Input Selection 158

6.12.3 Display Pattern and Operation of

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6.12.4 Display Pattern and Operation of

Triple Input Selection 161

6.12.5 Display Pattern and Operation of

Four Input Selection 163

6.13 VALIDATION OF SOFTWARE MODEL

WITH THE EXPERIMENTAL RESULTS 165

7 CONCLUSIONS 168

7.1 INTRODUCTION 168

7.2 CHLORIDE DIFFUSION 168

7.3 RAPID CHLORIDE PENTRATION VALUE 169

7.4 CONCRETE RESISTIVITY 170

7.5 WATER PERMEABILITY 171

7.6 ACCELERATED CORROSION

INITIATION TIME 171

7.7 DEPTH OF CHLORIDE ION PENETRATION

IN TIDAL ZONE 173

7.8 CORRELATIONS BETWEEN DURABILITTY PROPERTIES AND SERVICE LIFE

ESTIMATION 173

7.9 SERVICE LIFE PREDICTION MODEL 174

7.10 VALIDATION OF MODEL 174

7.11 CONTRIBUTIONS 174

7.12 SCOPE FOR FURTHER RESEARCH 174

REFERENCES 176

LIST OF PUBLICATIONS 184

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TABLE NO. TITLE PAGE NO.

2.1 Existing Durability Test Methods 21

3.1 Test Carried Out on Raw Materials 36

3.2 Physical and Engineering Properties of Raw

Materials 37

3.3 Chemical Composition of Fly Ash 37

3.4 Chemical Composition of GGBS 38

3.5 Properties of Superplasticizer (As per the

Manufacturer) 38

3.6 Details of Concrete Mixtures with out

Admixtures 39

3.7 Details of Concrete Mixtures with Fly Ash 39

3.8 Details of Concrete Mixtures with GGBS 39

3.9 Details of Concrete Mixtures with Corrosion

Inhibitors 40

3.10 Details of Mix Proportions With out Mineral

Admixture 40

3.11 Details of Mix Proportion with Fly Ash 41

3.12 Details of Mix Proportion with GGBS 41

3.13 Details of Mix Proportion with Corrosion

Inhibitors 41

3.14 Compressive Strength of Different Mixes 42

3.15 Flexural and Split Tensile Strength of Mixes

with Inhibitors (28 days) 43

3.16 Corrosion Risk from Resistivity 49

3.17 Parameters Monitored in Polarization Test 53 3.18 Specimen Details for Studying the Effect of 60

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Cover Thickness Under Accelerated Corrosion Test

3.19 Properties of Coating Materials 61

3.20 Consumption of Coating Materials Applied

Over Concrete Specimen Surface 64

3.21 Parameters Monitored for Diffusion Test 65

3.22 Parameters Monitored for RCPT Test 67

3.23 Details of Mixes Chosen for Preparation of Test

Specimens Placing in Tidal Zone 72

4.1 Depth of Chloride Penetration in Concretes of Different Types Exposed to Marine

Environment 124

4.2 Durability Properties of Concretes of Various Grades with Fly Ash and GGBS and Corrosion

Inhibitors 128

5.1 Service Life Estimation of Concrete of

Different Mixtures Based on Chloride Diffusion

Values 139

6.1 Details of Mixes chosen for validation 166

6.2 Durability Properties of Mixes studied for

validation Purposes 166

6.3 Comparison of Experimental Results of

Mix-Val-1 with the Data Obtained from the Model 166 6.4 Comparison of Experimental Results of

Mix-Val-2 with the Data Obtained from the Model 167 6.4 Comparison of Experimental Results of

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LIST OF FIGURES

FIGURE NO. TITLE PAGE NO.

2.1 Corrosion of Steel in Concrete by Chloride Attack

10

2.2 Service Life Model Design 11

3.1 Details of One Half of the Test Cell 45

3.2 Layout of Diffusion and RCPT Experiment Unit

45

3.3 Resistivity Measurement 49

3.4 German Water Permeability Apparatus Test Setup

50

3.5 Test Set Up for Polarization Experiment 52

3.6 Specimen Set for Polarization Study 53

3.7 Concrete specimens Cast Using Cylindrical Mould

55

3.8 Marking on the Specimen for Identity 55

3.9 Concrete Cylinders after 28 Days of Curing 56 3.10 Sizing of Specimen Using Diamond Saw

Concrete Cutter

56

3.11 Prepared Specimens with Markings for RCPT and Chloride Diffusion Tests

57

3.12 Steel Bars with Insulation Tape and Coated with Epoxy

58

3.13 Casting of Concrete Cylindrical Specimen with Re- Bars

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3.14 Typical Details of Test Specimen 59

3.15 Specimens for Polarization Test 60

3.16 Preparation of Putty by Mixing Different

Ingredients 62

3.17 Application of Putty Over Specimen Surface 62

3.18 Specimens with Primer Coat 63

3.19 Surface Coating in Progress 63

3.20 Specimens with Three Types of Coating 64

3.21 Diffusion Test Setup 65

3.22 Rapid Chloride Permeability Test Setup 67

3.23 Measurement of Concrete Resistivity 68

3.24 Specimens Placed Under Polarization Test

(TMT bars) 70

3.25 Specimens Placed Under Polarization Test

(CRS bars) 71

4.1 Typical Chloride Profile of M25 Concrete 74

4.2 Chloride Profile of M40 Grade Concrete 75

4.3 Effect of Concrète Grades on Chloride

Diffusion 76

4.4 Effect of Fly Ash on Chloride Diffusion in

Different Grades of Concretes 77

4.5 Effect of GGBS on Chloride Diffusion in

Different Grades of Concretes 78

4.6 Compressive Strength of Concrete with

Calcium Nitrate Inhibitors at Different Ages 79 4.7 Compression Strength of Concrete with

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4.8 Compressive Strength of Concrete with

Monothanolamine at Different Ages 81

4.9 Flexural Strength of Concrete with Calcium

Nitrate at the Age of 28 Days 82

4.10 Flexural Strength of Concrete with Sodium

Nitrite at the Age of 28 Days 83

4.11 Flexural Strength of Concrete with

Monothanolmine at the Age of 28 Days 84

4.12 Split Tensile Strength of Concrete with and without Calcium Nitrate at the Age of 28

Days 85

4.13 Split Tensile Strength of Concrete with

Sodium Nitrite at the Age of 28 Days 86

4.14 Split Tensile Strength of Concrete with

Monoethanolamine at the Age of 28 Days 87 4.15 Effect of Calcium Nitrate Inhibitors in

Concrete on Chloride Diffusion 88

4.16 Effect of Sodium Nitrite Inhibitors in

Concrete on Chloride Diffusion 89

4.17 Effect of Monoethanolamine Inhibitors in

Concrete on Chloride Diffusion 89

4.18 Effect of Concrete Grades on RCPT 91

4.19 Effect of Fly Ash on RCPT in Different

Grades of Concrete 92

4.20 Effect of GGBS on RCPT in Different

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4.21 Effect of Calcium Nitrate on RCPT in

Concrete 94

4.22 Effect of Sodium Nitrite on RCPT in

Concrete (28 days) 95

4.23 Effect of Monoethanolamine on RCPT in

Concrete (28 days) 95

4.24 Effect of Concrete Grades on Resistivity 97

4.25 Effect of Fly Ash on Resistivity in Different

Grades of Concrete 97

4.26 Effect of GGBS on Resistivity in Different

Grades of Concrete 99

4.27 Effect of Calcium Nitrate on Resistivity in

Concrete 99

4.28 Effect of Sodium Nitrite on Resistivity in

Concrete 100

4.29 Effect of Monoethanolamine on Resistivity in

Concrete 101

4.30 Effect of Concrete Grades on Water

Permeability 102

4.31 Effect of Fly Ash on Water Permeability in

Different Grades of Concretes 104

4.32 Effect of GGBS on Water Permeability in

Different Grades of Concretes 105

4.33 Effect of Calcium Nitrate Inhibitor on Water

Permeability in Concrete 106

4.34 Effect of Sodium Nitrite Inhibitor on Water

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4.35 Effect of Monoethanolamine Inhibitor on

Water Permeability in Concrete 107

4.36 Current Intensity for Concrete of M25 and M35 Under Accelerated Corrosion Test (29.5

mm cover thickness) 108

4.37 Effect of Concrete Grades on Corrosion

Initiation Time 109

4.38 Current Intensity of Concrete of M25 and M35 with Fly Ash as CRM Under

Accelerated Corrosion Test (29.5 mm cover

thickness) 110

4.39 Effect of Fly Ash on Corrosion initiation

Time in Different Grades of Concrete 111 4.40 Current Intensity of Concrete of M40 and

M60 with 40% GGBS as CRM Under Accelerated Corrosion Test (29.5 mm cover

thickness) 112

4.41 Effect of Ground Granulated Blast Furnace Slag on Corrosion Initiation Time in

Different Grades of Concrete 113

4.42 Effect of Calcium Nitrate on Corrosion

Initiation Time in Concrete 113

4.43 Effect of Sodium Nitrite on Corrosion

Initiation Time in Concrete 114

4.44 Effect of Monoethanolamine on Corrosion

Initiation Time in Concrete 115

4.45 Condition of Un-Coated Specimens at the

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4.46 Condition of Un-Coated Specimens Continued Till the Coated Specimens to

Reach the End of Corrosion Initiation Period 116 4.47 Condition of Coated Specimens at the End of

Corrosion Initiation Period 116

4.48 Current Vs Rime for Coated and Un-Coated

Specimens 117

4.49 Corrosion Initiation Period for Concrete

Specimens with and with out Coating 118

4.50 Effect of Concrete Cover Thickness on

Corrosion Initiation Time 119

4.51 Effect of Concrete Cover Thickness on

Corrosion Initiation Time in Different Grades 119 4.52 Effect of Fly Ash and Concrete Cover

Thickness on Corrosion Initiation Time 120 4.53 Effect of Fly Ash on Corrosion Initiation

Time in Concrete of Different Grades and

Cover Thickness 121

4.54 Effect of GGBS in Concrete and Cover

Thickness on Corrosion Initiation Time 121 4.55 Effect of GGBS on Corrosion Initiation Time

in Concrete of Different Grades and Cover

Thickness 122

4.56 Effect of Corrosion Inhibitor and Concrete Cover Thickness on Corrosion Initiation

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4.57 Effect of Various Corrosion Inhibitors in Concrete and Cover Thickness on

Accelerated Corrosion Initiation Time 123 4.58 Chloride Ion Penetration Depth of Concretes

Placed in Tidal Zone 125

4.59 Comparison of Chloride Diffusion Values Arrived Based on Marine and Accelerated

Tests Conditions 126

5.1 Relationship Between RCPT and Chloride

Diffusion Values 131

5.2 Relationship Between RCPT and Resistivity

Values 131

5.3 Relationship Between Water Permeability

and RCPT 132

5.4 Relationship Between Water Permeability

and Resistivity 133

5.5 Relationship Between Corrosion Initiation

Time and RCPT 134

5.6 Relationship Between Corrosion Initiation

Time and Resistivity 135

5.7 Relation Between RCPT and the Corrosion

Initiation Time 139

6.1 Modules Pattern 148

6.2 Flow Diagram of Single Input Module for

Service Life Prediction of RCC Structures 149 6.3 Flow Diagram of Double Input Module for

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6.4 Flow Diagram of Triple Input Module for

Service Life Prediction of RCC Structures 151 6.5 Flow Diagram of Four Input Module for

Service Life Prediction of

RCC Structures 152

6.6 Starting Screen of the Service Life Prediction

Model 157

6.7 Selection Screen for Input Data 157

6.8 Display Screen for the RCPT Selection

Mode 158

6.9 Display Screen After Entering the RCPT , Cover Thickness, Steel Type and the

Environmental Condition 159

6.10 Graphical and Numerical Results 159

6.11 Display Screen for the RCPT and Diffusion

Values Selection 160

6.12 Graphical and Numerical Results 161

6.13 Display Screen for the RCPT, Diffusion and

Resistivity Values Selection 162

6.14 Graphical and Numerical Results 163

6.15 Display Screen for the RCPT, Diffusion, Resistivity and Water Permeability Values

Selection 164

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LIST OF SYMBOLS AND ABBREVIATIONS

A - Ampere

ASTM - American Society for Testing Materials

BS - Black Steel Bar

cm - Centimeter

cm2 - Square centimeter

cm2/ sec - Square centimetre per second

CRM - Cement Replacement Materials

EC - Epoxy Coated Bar

CR - Corrosion Resistant Bar

DC(Q) - Chloride Diffusion based on RCPT

DC(R) - Chloride Diffusion based on Resistivity

DC(P) - Chloride Diffusion based on Permeability

Dc - Diffusion Coefficient

Env. - Environment

FA - Fly ash

Fig. - Figure

g - Gram

GGBS - Ground Granulated Blast furnace Slag

HPC - High Performance Concrete

kg - Kilogram

M - Molarity

m2/ s - Square meter per second

Max. - Maximum

mA - milli Ampère

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mmol/ cm3 s - milli mole per cubic centimeter second

mol/L - mole per liter

MA - Mineral Admixture

N - Normality

OPC - Ordinary Portland Cement

P - Permeability

Q - RCPT

RCPT - Rapid Chloride Permeability Test

R - Resistivity

SCM - Supplementary Cementing Materials

SP - Superplasticizer

SF - Silica Fume

SS - Stainless Steel Bar

Ti - Accelerated Corrosion Initiation Time

ACIT - Actual Corrosion Initiation Time

tp - Propagation Period

Sl - Service Life

Ta (Q) - Actual Corrosion Initiation Time based on RCPT

Ta (D)

-Actual Corrosion Initiation Time based on Chloride Diffusion

Ta (R) - Actual Corrosion Initiation Time based on Resistivity

Ta (P) - Actual Corrosion Initiation Time based on Permeability

V - Volt

w/b Ratio - Water-Binder ratio w/c Ratio - Water-Cement ratio

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