221.1R-98
Report on Alkali-Aggregate Reactivity
1998, 31 pp.
$61.50

Information that is currently available on alkali-aggregate reactivity (AAR), including alkali-silica reactivity (ASR) and alkali-carbonate reactivity (ACR) is summarized in the report. Chapters are included that provide an overview of the nature of ASR and ACR reactions, means to avoid the deleterious effects of each reaction, methods of testing for potential expansion of aggregates and cement-aggregate combinations, measures to prevent deleterious reactions, and recommendations for evaluation and repair of existing structures.

Contents:
Chapter 1 - Introduction

1.1 Historical perspective

1.2 Scope of report

Chapter 2 - Manifestations of Distress Due to Alkali-Silica Reactivity

2.1 Introduction

2.2 Cracking mechanisms

2.3 Expansion & other indicators of alkali-silica reactivity

2.4 Alkali-silica reactivity reaction factors

2.5 Microscope evidence of alkali-silica reactivity

Chapter 3 - Alkali-Silica Reactivity mechanisms

3.1 Factors influencing the reaction

3.2 Basic mechanisms of reaction & expansion

Chapter 4 - Petrography of Alkali-Silica Reactive Aggregate

4.1 Introduction

4.2 Potentially reactive natural siliceius constituents

4.3 Potentially reactive synthetic materials

Chapter 5 - Measures to Prevent Alkali-Silica Reactivity

5.1 Overview

5.2 Limiting Moisture

5.3 Aggregate selection

5.4 Minmizing alkalies

5.5 Cement selection

5.6 Finely divided materials other than portland cement

5.7 Testing for the effictiveness of pozzolans or slags

5.8 Alkali content of concrete

5.9 Chemical admixtures

5.10 Other methods

Chapter 6 - Methods to Evaluate Potential for Expansive

Alkali-Silica Reactivity

6.1 Introduction

6.2 Field service record

6.3 Common tests to evaluate potential alkali-silica

reactivity of aggregates

6.4 Less common tests to evaluate potential alkali-silica

reactivity of aggregates

6.5 Tests to evaluate alkali-silica reactivity in hardened

concrete

6.6 Summary of testing

Chapter 7 - Manifestation of Distress Due to Alkali-Carbonate

Reactivity

7.1 Overview

7.2 Field indicators

7.3 Microscope indicators

7.4Role of environment, structure geometry, and

restraint on distress development

Chapter 8 - Alkali-Carbonate Reactivity Mechanisms

8.1 Overview

8.2 Characteristics of alkali-carbonate reactive rocks

8.3 Mechanism of reaction and expansion

Chapter 9 - Measures to Prevent Alkali-Carbonate Reactivity

9.1 Introduction

9.2 Aggregate selection

9.3 Cement

9.4 Pozzolans

9.5 Moisture

Chapter 10 - Methods to Evaluate Potential for Expansive Alkali-Carbonate Reactivity

10.1 Introduction

10.2 Field service record

10.3 Petrographic examination

10.4 Rock cylinder test

10.5 Concrete prism tests

10.6 Other procedures

10.7 Evaluation of new aggregate sources

Chapter 11 - Evaluation & Repair of Structures Affected

by Alkali-Aggregate Reactivity

11.1 Introduction

11.2 Evaluation

11.3 Repair methods and materials

Chapter 12 - References

12.1 Standards documents

12.2 Cited references