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Mechanism of alkali-silica reaction and the significance of calcium hydroxide

✍ Scribed by H. Wang; J.E. Gillott

Publisher
Elsevier Science
Year
1991
Tongue
English
Weight
415 KB
Volume
21
Category
Article
ISSN
0008-8846

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✦ Synopsis

Experiments indicate that Ca(OH)2 [CH] aggravates alkali-silica reaction causing increased expanslon of mortar bars. Ca(OH) 2 has two major functions:

firstly it acts a "buffer" to maintain a high pH, i.e. a high concentration of hydroxyl ions in pore solutions; secondly, Ca++ ions may exchange for alkali ions on silica gel leading to further production of swelling alkalisilica complex.

A mechanism of alkali-silica reaction is proposed which emphasizes the effect of Ca(OH)2 on reaction and expansion.

πŸ“œ SIMILAR VOLUMES

A reply to a discussion by S. Chatterji
A reply to a discussion by S. Chatterji of the paper β€œMechanism of alkali-silica reaction and the significance of calcium hydroxide”
✍ H. Wang; J.E. Gillott πŸ“‚ Article πŸ“… 1992 πŸ› Elsevier Science 🌐 English βš– 128 KB

We would like to thank Dr. Chatterji for his interesting and detailed comments on our paper. We agree with Dr. Chatterji that our thinking owes a great deal to the pioneering work of Powers and Steinour though our new data has led us to propose what we feel are significant changes to the original hy

A discussion of the paper β€œMechanism of
A discussion of the paper β€œMechanism of alkali-silica reaction and the significance of calcium hydroxide” by H. Wang and J.E. Gillot
✍ S. Chatterji πŸ“‚ Article πŸ“… 1992 πŸ› Elsevier Science 🌐 English βš– 167 KB

This is a very interesting and informative paper. In this paper the authors have attempted to resuscitate Powers-Steinour hypothesis of alkali-silica reaction. In their scheme calcium ion has given an added role of the rejuvenator of alkali hydroxide and the effects of the hydraulic radii of differe

Studies of alkali-silica reaction, part
Studies of alkali-silica reaction, part 6. Practical implications of a proposed reaction mechanism
✍ S. Chatterji; N. Thaulow; A.D. Jensen πŸ“‚ Article πŸ“… 1988 πŸ› Elsevier Science 🌐 English βš– 244 KB

In this paper various practical implications of a recently proposed alkali-silica reaction mechanism have been expressed in a coherent fashion. Aspects of alkali-silica reaction considered are: long latency, sources of alkalies, relative aggressivity of sodium and potassium ions, reduction of expans

Studies of alkali-silica reaction. part
Studies of alkali-silica reaction. part 5. Verification of a newly proposed reaction mechanism
✍ S. Chatterji; N. Thaulow; A.D. Jensen πŸ“‚ Article πŸ“… 1989 πŸ› Elsevier Science 🌐 English βš– 344 KB

To explain the roles of Ca(OH) 2 and alkali chlorides in alkali-silica reaction, it has been proposed that during the chemical reaction alkali and hydroxyl ions enter the reactive silica grains leaving behind Ca and chloride ions in the liquid