Documents last published in CSA A23.1 Concrete materials and methods of concrete construction

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1 Canadian St tandards on Alkali-Aggregate reactions Benoit Fournier Laval University, Quebec City, Canada ASTM 2010 Spring Meeting St. Louis s, Missouri

2 CSA A 23.1 & A23.2 on AAR Documents last published in 2009 (five-year cycle) CSA A23.1 Concrete materials and methods of concrete construction CSA A23.2 Test methods and standard practices for concrete

3 CSA A 23.1 & A23.2 on AAR AAR-related specifications CSA A23.1 requires that aggregates be non reactive or that preventive measures be taken CSA A23.2 Three test methods and two standard practices to detect and prevent AAR 15% of CSA standards A23.1 A23.2 deal with AAR &

4 CSA A 23.1 Appen ndix B General Informative Types of alkali-aggregate reactions Methods for evaluating potential reactivity of aggregates (current and other methods) Distribution of potentially-reactive aggregates across Canada Measures to prevent AAR in concrete incorporating potentially reactive aggregates Reactivity i of reclaimed concrete for use as recycled aggregate Summary

potential reactivity of aggregates (current and other methods) Distribution of

5 Testing for AAR CSA Standard Practice A A: Step-by-step procedu ure for: 1) determining potential alkali- reactivity of aggregates, and 2) selecting preventive measures against ASR using a risk analysis approach.

6 Standard Practice CSA A A 27A Evaluating of poten ntial alkali-reactivity of concrete aggregates Field performance survey Laboratory test program» Petrographic examination: ACR & ASR (ASTM C 295)» Chemical Method: ACR (CSA A A)» Accelerated Mortar Bar Method: RAS (CSA A A)» Concrete Prism Test: RAC & RAS (CSA A A)

performance survey Laboratory test program» Petrographic examination: ACR & ASR

7 F Field Perfoormance Surveyy of AAR

9 Laboratory investigations Petrographic Examination Aggregates other than quarried carbonate rocks Option: no testing; the aggregate is considered highly reactive Select preventive measure Quarried carbonate rocks Chemical Method for ACR PR > limit Not PR Other rock types Accelerated Mortar bar < limit test!? >li limitit Accept Concrete Prism Test < limit

preventive measure Quarried carbonate rocks Chemical Method for ACR PR > limit Not PR

10 Petrographic Examination Essential step: Nature of aggregate (ACR, ASR) Sl Select tbest ttest tto perform Risky to accept/reject aggregates based on petrographic examination only. ASR ASR ACR

11 Laboratory investigations Petrographic Examination Steel Slag Aggregates other than quarried carbonate rocks Option: no testing; the aggregate is considered highly reactive Select preventive measure Quarried carbonate rocks Chemical Method for ACR PR > limit Not PR Other rock types Reject Accelerated Mortar bar < limit test!? >li limitit Accept Concrete Prism Test < limit

preventive measure Quarried carbonate rocks Chemical Method for ACR PR > limit Not PR Other

12 Chemical Method for ACR Screen test for quarried carbonate rocks * Chemical analysis for Al 2 O 3, MgO and CaO Zones for aggregates considered potentially expansives or non-expansives (ACR) Next step Concrete p Prism Test

and CaO Zones for aggregates considered potentially

13 Chemical Method ACR for ACR Screen test for quarried carbonate rocks Chemical analysis for Al 2 O 3, MgO and CaO Zones for aggregates considered potentially expansives or non-expansives (ACR) Next step Concrete Prism Test % Al 2 O 3 Test Method CSA A A

aggregates considered potentially expansives or non-expansives

14 Laboratory investigations Petrographic Examination Steel Slag Aggregates other than quarried carbonate rocks Option: no testing; the aggregate is considered highly reactive Select preventive measure Quarried carbonate rocks Chemical Method for ACR PR > limit Not PR Other rock types Reject Accelerated Mortar bar < limit test!? >li limitit Accept Concrete Prism Test < limit

15 Accelerated Mortar r Bar Test (AMBT) Bars immersed in 1N NaOH solution at 80 o C for 14 days

16 Laboratory investigations Petrographic Examination Steel Slag Aggregates other than quarried carbonate rocks Option: no testing; the aggregate is considered highly reactive Select preventive measure Quarried carbonate rocks Chemical Method for ACR PR > limit Not PR Other rock types Reject Accelerated Mortar bar < limit test!? >li limitit Accept Concrete Prism Test < limit

17 Concrete Prism Test

18 Concrete Pris sm Test (CPT) limit of 0.04% Testing potential ASR and ACR of coarse or fine aggregates Best test method available but often considered too long (one year) at one year Expan nsion (%) CSA Limit Age (Months)

aggregates Best test method available but often considered

19 Testing for AAR CSA Standard Practice A A: Step-by-step pprocedure for: 2) selecting preventive measures against ASR using a risk analysis approach based on:» Degree of reactivity of the agggregate» Size of element and environmental conditions» Expected service life of the structure

against ASR using a risk analysis approach based on:» Degree of

20 Testing for AAR CSA Standard Practice A A: 28A: Laboratory testing to demonstrate the effectiveness of SCMs and chemical admixtures (LiNO 3 ) to prevent ASR in concrete» Concrete Prism Test» Accelerated mortart tbar Test

1.5 Concrete (Part I)

1.5 Concrete (Part I) This section covers the following topics. Constituents of Concrete Properties of Hardened Concrete (Part I) 1.5.1 Constituents of Concrete Introduction Concrete is a composite material