Science and technology of concrete admixtures / edited by Pierre-Claude Aïtcin and Robert J. Flatt.

Format:

Book

Contributor:

Aïtcin, Pierre-Claude, editor.

Flatt, Robert J., editor.

Series:

Woodhead Publishing series in civil and structural engineering ; number 59.

Woodhead Publishing series in civil and structural engineering ; number 59

Language:

English

Subjects (All):

Concrete--Additives.

Concrete.

Physical Description:

1 online resource (668 p.)

Edition:

1st ed.

Place of Publication:

Cambridge : Elsevier, [2016]

Summary:

Science and Technology of Concrete Admixtures presents admixtures from both a theoretical and practical point-of-view. The authors emphasize key concepts that can be used to better understand the working mechanisms of these products by presenting a concise overview on the fundamental behavior of Portland cement and hydraulic binders as well as their chemical admixtures, also discussing recent effects in concrete in terms of rheology, mechanics, durability, and sustainability, but never forgetting the fundamental role played by the water/binder ratio and proper curing in concrete technology. Part One presents basic knowledge on Portland cement and concrete, while Part Two deals with the chemical and physical background needed to better understand what admixtures are chemically, and through which mechanism they modify the properties of the fresh and hardened concrete. Subsequent sections present discussions on admixtures technology and two particular types of concrete, self-consolidating and ultra-high strength concretes, with final remarks on their future. Combines the knowledge of two leading authors to present both the scientific and technology of admixtures Explains what admixtures are from a chemical point-of-view and illustrates by which mechanisms they modify the properties of fresh and hardened concrete Presents a fundamental, practical, and innovative reference book on the topic Contains three detailed appendices that can be used to learn how to use admixtures more efficiently

Contents:

Front Cover

Related titles

Science and Technology of Concrete Admixtures

Copyright

Contents

About the contributors

Woodhead Publishing Series in Civil and Structural Engineering

Preface

References

Acknowledgments

Introduction

Terminology and definitions

Cement, cementitious materials, binders, fillers

Binary, ternary, and quaternary cements (or binders)

Cementitous material content

Specific surface area

Alite and belite

Hemihydrate

Water-cement, water-cementitious materials, water-binder ratios

Saturated surface-dry state for an aggregate (SSD state)

Water content, absorption, moisture content of an aggregate

Specific gravity

Superplasticizer dosage

Eutectic

Reference

Glossary

Historical background of the development of concrete admixtures

Early developments

The development of the science of admixtures

The use of admixtures

The use of synthetic molecules and polymers

An artificially complicated terminology

Classification of admixtures

The importance of cement particles dispersion

One - Theoretical background on Portland cement and concrete

1 - The importance of the water-cement and water-binder ratios

1.1 Introduction

1.2 The hidden meaning of the w/c

1.3 The water-cement and water-binder ratios in a cement paste made with a blended cement

1.3.1 Case of a blended cement containing a supplementary cementitious material

1.3.2 Case of a blended cement containing some filler

1.3.3 The relative importance of the w/c and w/b ratios

1.4 How to lower the w/c and w/b ratios

1.5 Conclusion

2 - Phenomenology of cement hydration

2.1 Introduction

2.2 Le Chatelier's experiment

2.3 Powers' work on hydration.

2.3.1 Hydration of a cement paste having a w/c ratio equal to 0.42

2.3.1.1 Hydration in a closed system

2.3.1.2 Hydration under water

2.3.2 Hydration of a cement paste having a w/c ratio equal to 0.36 cured under water

2.3.3 Hydration of a cement paste having a w/c ratio equal to 0.60 cured in a closed system

2.3.4 Hydration of a cement paste having a w/c ratio of 0.30

2.3.4.1 Hydration in a closed system

2.3.4.2 Hydration under water

2.4 Curing low w/c ratio concretes

2.4.1 Different types of shrinkage

2.4.2 Curing concrete according to its w/c ratio

2.5 Conclusion

3 - Portland cement

3.1 Introduction

3.2 The mineral composition of Portland cement clinker

3.3 The fabrication of clinker

3.4 Chemical composition of Portland cement

3.5 The grinding of Portland cement

3.5.1 Influence of the morphology of the cement particles

3.5.2 Why is calcium sulphate added when grinding Portland cement?

3.6 The hydration of Portland cement

3.7 Hydrated lime (portlandite)

3.8 Present acceptance standards for cements

3.9 Side-effects of hydration reaction

3.10 Conclusion

Appendices

Appendix 1

Tricalcium aluminate

Appendix 2

Ettringite

4 - Supplementary cementitious materials and blended cements

4.1 Introduction

4.2 Crystallized and vitreous state

4.3 Blast-furnace slag

4.4 Fly ashes

4.5 Silica fume

4.6 Calcined clays

4.7 Natural pozzolans

4.8 Other supplementary cementitious materials

4.9 Fillers

4.10 Ground glass

4.11 Blended cements

4.12 Conclusion

5 - Water and its role on concrete performance

5.1 Introduction

5.2 The crucial role of water in concrete

5.3 Influence of water on concrete rheology

5.4 Water and cement hydration

5.5 Water and shrinkage

5.5.1 General considerations.

5.5.2 How to eliminate the risk of plastic shrinkage

5.5.3 How to mitigate autogenous shrinkage

5.5.4 How to provide an internal source of water

5.5.5 How to eliminate drying shrinkage

5.6 Water and alkali/aggregate reaction

5.7 Use of some special waters

5.7.1 Seawater

5.7.2 Wastewaters from ready-mix operations

5.8 Conclusion

6 - Entrained air in concrete: rheology and freezing resistance

6.1 Introduction

6.2 Entrapped air and entrained air

6.3 Beneficial effects of entrained air

6.3.1 The beneficial effect of entrained air on the workability of fresh concrete

6.3.2 The beneficial action of entrained air against the propagation of cracks

6.3.3 The beneficial action of entrained air on the absorptivity and permeability of concrete

6.3.4 Trapping expansive products

6.3.5 The beneficial effect of entrained air on the resistance to freezing and thawing cycles

6.4 Effect of pumping on the air content and spacing factor

6.5 Entraining air in blended cements

6.6 Conclusion

7 - Concrete rheology: a basis for understanding chemical admixtures

7.1 Introduction

7.2 Definition of rheology

7.2.1 Shear laminar flow

7.2.2 Shear stress

7.2.3 Shear rate

7.2.4 Flow curve

7.3 Different rheological behaviours

7.3.1 Newtonian fluids

7.3.2 Bingham fluid

7.3.3 Shear-thinning and shear-thickening fluids with yield stress

7.4 Micromechanical behaviour of suspensions

7.4.1 Yield stress

7.4.2 Viscosity

7.4.3 Thixotropy

7.4.4 Concrete: A visco-elasto-plastic material

7.4.5 Bleeding and segregation

7.5 Factors affecting concrete rheology

7.5.1 General considerations

7.5.2 Effect of processing energy on concrete rheology

7.5.3 Effect of solid concentration on viscosity and yield stress.

7.5.4 Effect of paste/aggregate and mortar/aggregate ratio on the rheology of concrete

7.5.5 Effect of paste composition

7.5.5.1 Effect of water content

7.5.5.2 Effect of cement

7.5.5.3 Effect of mineral admixtures

7.5.5.4 Clays

7.5.6 Effect of air content on rheology of concrete

7.6 Thixotropy of concrete

7.6.1 Consequences of thixotropy on concrete processing

7.6.2 Experimental methods to quantify thixotropy

7.6.2.1 Hysteresis curves

7.6.2.2 Structural breakdown curves

7.6.2.3 Structural build-up at rest

7.7 Conclusions

Acknowledgements

8 - Mechanisms of cement hydration

8.1 Introduction

8.2 Hydration of C3A

8.3 Hydration of alite

8.3.1 Chemistry and stages of alite hydration

8.3.2 Stages 0 and I: initial dissolution

8.3.2.1 Protective membrane

8.3.2.2 Dissolution control

8.3.3 Stage II: the induction period

8.3.4 Stage III: the acceleration period

8.3.4.1 Structure of CSH

8.3.5 The deceleration period

8.4 Hydration of ordinary Portland cement

8.4.1 Stages of cement hydration

8.4.2 Silicate-aluminate-sulfate balance

8.5 Conclusions

Two - Chemistry and working mechanisms

9 - Chemistry of chemical admixtures

9.1 Introduction

9.2 Water reducers and superplasticizers

9.2.1 Introduction

9.2.2 Natural polymers

9.2.2.1 Lignosulphonates

9.2.2.2 Casein

9.2.3 Linear synthetic polymers

9.2.3.1 Polynaphthalene sulphonates (PNS)

9.2.3.2 Polymelamine sulphonates

9.2.3.3 Phosphonate-terminated PEG brushes

9.2.3.4 Vinyl copolymers

9.2.4 Comb-shaped copolymers

9.2.4.1 Chemical nature of the backbone

9.2.4.2 Chemical nature of side chains

9.2.4.3 Characterization of comb-shaped superplasticizers

9.2.4.4 Conformation of PCEs in solution.

9.3 Retarders

9.3.1 Introduction

9.3.2 Carbohydrates

9.3.2.1 Monosaccharides

9.3.2.2 Disaccharides

9.3.2.3 Oligosaccharides

9.3.2.4 Polysaccharides

9.4 Viscosity-modifying admixtures

9.4.1 Introduction

9.4.2 Natural polymers

9.4.2.1 Welan gum and diutan gum

9.4.3 Semi-synthetic polymers

9.4.3.1 Cellulose-ether derivatives

9.4.3.2 Guar gum derivatives

9.4.3.3 Modified starch

9.4.4 Synthetic polymers

9.4.4.1 Polyethylene oxide

9.4.4.2 Polyacrylamides

9.4.5 Inorganic powders

9.5 Air-entraining admixtures

9.5.1 Introduction

9.5.2 General features of surfactants

9.5.2.1 Basic structural features

9.5.2.2 The concept of hydrophile-lipophile balance

9.5.3 Sources for air-entraining admixtures

9.5.4 Anionic surfactants

9.5.4.1 Carboxylic acid salts

9.5.4.2 Sulphonic acid salts

9.5.4.3 Sulphuric acid ester salts

9.5.4.4 Taurates

9.5.5 Cationic surfactants

9.5.6 Amphoteric surfactants

9.5.7 Non-ionic surfactants

9.6 Shrinkage-reducing admixtures

9.6.1 Introduction

9.6.2 History and working mechanism of SRAs

9.6.3 General features and overview of surfactants used in SRAs

9.6.4 Classes of compounds used in SRAs

9.6.4.1 Monoalcohols

9.6.4.2 Glycols

9.6.4.3 Polyoxyalkylene glycol alkyl ethers

9.6.4.4 Polymeric surfactants

9.6.4.5 Other SRAs

9.7 Conclusions

10 - Adsorption of chemical admixtures

10.1 Introduction

10.2 Adsorption and fluidity

10.2.1 Initial fluidity

10.2.2 Fluidity retention

10.3 Adsorption isotherms

10.3.1 Basic phenomenology of adsorption

10.3.2 Simple adsorption isotherm models

10.3.3 Linear zone of adsorption isotherms of superplasticizers

10.3.4 Specific issues in studying adsorption on cementitious systems

10.4 Molecular structure and adsorption.

10.4.1 General features.

Notes:

Description based upon print version of record.

Includes bibliographical references and index.

Description based on online resource; title from PDF title page (ebrary, viewed December 8, 2015).

ISBN:

0-08-100693-4

0-08-100696-9

OCLC:

936863098