Handbook on Concrete Mixes (Based on Indian Standards)
CONTENTS
1. INTRODUCTION
1.1 Concrete Mix as a System
1.2 Classification of Concrete Mixes
1.2.1 Grades of Concrete
2. CONCRETE MAKING MATERIALS
2.0 General
2.1 Cements
2.1.1 Hydration of Cements
2.1.2 Portland Pozzolana and Slag Cements
2.1.3 Tests on Cements
2.2 Aggregates
2.2.1 Classification of Aggregates
2.2.1.1 General
2.2.1.2 Geological Classification of Natural ,Aggregates
2.2.2 Properties of Natural Aggregates
2.2.2.1 Mechanical Properties
2.2.2.2 Particle Shape and Texture
2.2.2.3 Porosity and Absorption
2.2.2.4 Deleterious Constituents
2.2.2.5 Soundness of Aggregates
2.2.2.6 Alkali-Aggregate Reaction
2.2.3 Lightweight Aggregates
2.3 Water
2.3.1 Miscellaneous Inorganic Impurities
2.3.2 Silt or Suspended Clay Particles
2.3.3 Oil Contamination
2.3.4 Sea Water
2.3.5 Curing Water
2.4 Admixtures
Accelerating Admixtures 27
Retarding Admixtures 28
Water-Reducing Admixtures
Air-Entraining Admixtures 29
Information on Admixtures 29.
3. PROPERTIES OF-FRESH AND HARDENED CONCRETE
3.0 Introduction 55
3.1 Workability 55
3.1.1 Different Measures of Workability 55
3.1.2 Factors Affecting Workability 56
3.1.2.1 Influence of Materials and Mix Proportions 56
3.1.2.2 Effects of Time and Temperature on Workability 57
3.1.3 Requirement of Workability 58
3.2 Compressive Strength 58
3.2.1 Influence of Mix Proportions 58
3.2.2 Effect of Placing, Compaction and Curing 60
3.2.2.1 Steam Curing of Concrete 60
3.2.3 Relation with Tensile Strength 61
3.3 Durability of Concrete 62
4. VARIABILITY OF CONCRETE STRENGTH - STATISTICAL ASPECTS
4.1 Measures of Variabilities of Concrete Strength
4.1.1 Factors Contributing to Variability
4.1.2 The Distribution of Results
4.1.3 Characteristic Strength
4.1.4 Target Mean Strength
4.2 Statistical Concepts in Concrete Mix Design
4.3 Acceptance Criteria
5. PRINCIPLES OF CONCRETE MIX DESIGN
5.1 Basic Considerations 95
5.2 Factors in the Choice of MixDesign 95
5.3 Outline of Mix Design Procedure 96
6. METHODS OF CONCRETE MIX DESIGN
6.0 Introduction
6.1 The AC1 Mix Design Practice
6.2 The USBR Mix Design Practice
6.3 The British Mix Design Method (DOE Method)
6.4 Mix Design in Accordance with Indian Standard Recommended Guidelines for Concrete Mix Design
7. EXTREME WEATHER CONCRETING
7.1 Hot Weather Concreting 12s
7.1.1 Effects of Hot Weather on Concrete 12s
7.1.2 Recommended Practices and Precautions 126
7.1.2. I Temperature Control of Concrete Ingredients 126
127 7.1.2.2 Proportioning of Concrete Mix Materials and Mix Design
7.1.2.3 Production and Delivery
7.1.2.4 Placement, Protection and Curing
7.2 Cold Weather Concreting
7.2.1 Effects of Cold Weather on Concreting
7.2.2 Recommended Practice
7.2.2.1 Temperature Control of Concrete Aggregates
7.2.2.2 Use of Insulating Formwork
7.2.2.3 Proportioning of Concrete Ingredients
7.2.2.4 Placement, Protection and Curing
7.2.2.5 Delayed Removal of Formwork
8. TESTING OF CONCRETE MIXES
8.1 Sampling and Testing of Concrete 139
8.2 Frequency of Sampling 139
8.3 Workability Tests of Fresh Concrete 139
8.4 Analysis of Fresh Concrete 140
8.5 Measurement of Air Content 140
8.6 Setting Time of Concrete 140
8.7 Tests for Strength 141
8.8 Analysis of Hardened Concrete 142
