Towards a Global System for Preventing Alkali-Reactivity: The Continuing Work of RILEM TC 191-ARP

ABOUT THE INTERNATIONAL CONCRETE ABSTRACTS PORTAL

  • The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.

International Concrete Abstracts Portal

  


Title: Towards a Global System for Preventing Alkali-Reactivity: The Continuing Work of RILEM TC 191-ARP

Author(s): I. Sims and P. J. Nixon

Publication: Special Publication

Volume: 212

Issue:

Appears on pages(s): 475-489

Keywords: alkali-aggregate reaction (AAR); alkali-carbonate reactivity (ACR); alkali-silica reactivity (ASR); accelerated testing; aggregates concrete; alkali-reactivity; alkali release; carbonate aggregates; diagnosis; pterography; specification; testing

Date: 6/1/2003

Abstract:
Since 1988, RILEM has been seeking to establish universally applicable test methods for assessing the alkali-reactivity potential of aggregates. Technical committee TC 106 (1988-2000) published two expansion tests (AAR-2 & AAR-3), following international trials, and started to develop two further procedures (AAR-1 & AAR-4), together with an integrated assessment scheme (AAR-0). Successor committee TC 191-ARP (formed in 2000). comprising members from all parts of the world, is now working to finalise procedures AAR-1 & AAR-4 and additionally has a widened scope, to include carbonate aggregates (AAR-5) and also to seek international consistency in approaches to diagnosis and specification. This paper will review the latest progress of TC 191-ARP and, in particular, will outline the principles behind the petrographical examination procedure (AAR-I), report the findings of the international trial of AAR-4 and describe draft recommendations for assessing carbonate materials. The importance of systematic and reliable diagnosis of deterioration in existing structures will be stressed and the initial guidance of TC 191-ARP explained. Finally, the desirability of a global system for preventing damage to concrete from alkali-reactivity will be advocated and the proposals of TC 191-ARP reviewed. The authors are respectively Secretary and Chairman of TC 191-ARP and previously of TC 106.