PSI - Issue 37

João Custódio et al. / Procedia Structural Integrity 37 (2022) 590–597

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João Custódio et al. / Structural Integrity Procedia 00 (2019) 000 – 000

The results attained with the RILEM AAR-3.1 tests confirmed that the aggregate used in the FHS dam is considered of having an ASR potential of Class II (potentially alkali-reactive or alkali-reactivity uncertain), indicated that the aggregates used in the BHS, CHS, DHS and EHS dams are of Class III (very likely to be alkali-reactive), and clarified that the aggregate of AHS dam is actually Class III. In terms of alkali-reactivity, the RILEM AAR-3.1 method resulted in the same order of alkali-reactivity as the AAR-4.1 method, namely: FHS < EHS < AHS < DHS < CHS < BHS. Petrographic qualitative evaluation per se could not explain the different alkali-reactivity levels observed in the expansion tests carried out. The findings will be updated upon completion of the expansion tests, quantitative petrographic analysis, SEM/EDX analysis, and short- and long-term alkali content determination tests. Acknowledgements João Custódio carried out the work in the scope of the FCT Investigator Project IF/00595/2015/CP1326/CT0001, financed by the Fundação para a Ciência e a Tecnologia, FCT (Portugal); the author wishes to acknowledge this financial support. References ASTM 2008. ASTM C1293-08b Standard test method for determination of length change of concrete due to alkali-silica reaction. West Conshohocken, PA: ASTM International. IPQ 1976. NP 1382:1976 Inertes para argamassas e betões. Determinação do teor de álcalis solúveis. Processo por espectrofotometria de chama (Aggregates for mortars and concretes. Determination of soluble alkali content. Flame spectrophotometry process). Caparica: Instituto Português da Qualidade, I.P. (IPQ). IPQ 2010. NP EN 12620:2002+A1:2010 Agregados para betão (Aggregates for concrete). Caparica: Instituto Português da Qualidade, I.P. (IPQ). IPQ 2017. NP EN 206:2013+A1:2017 Betão. Especificação, desempenho, produção e conformidade (Concrete. Specification, performance, production and conformity). Caparica: Instituto Português da Qualidade, I.P. (IPQ). LNEC 1993a. E 415:1993 Inertes para argamassas e betões. Determinação da reatividade potencial com os álcalis. Análise petrográfica (Aggregates for mortars and concretes. Determination of potential alkali-silica reactivity. Petrographic examination) (in Portuguese), Lisboa, Portugal: LNEC - Laboratório Nacional de Engenharia Civil, I.P. LNEC 1993b. LNEC Specification E 402:1993 Cementitious matrix materials. Energy dispersive X-ray microanalysis associated to scanning electron microscope (in Portuguese), Lisboa: Laboratório Nacional de Engenharia Civil, I.P. (LNEC). LNEC 2004. E 461:2004 Betões. Metodologias para prevenir reacções expansivas internas (Concrete. Methodologies for avoiding internal expansive reactions), Lisboa: Laboratório Nacional de Engenharia Civil, I.P. (LNEC). LNEC 2007a. E 461:2007 Betões. Metodologias para prevenir reacções expansivas internas (Concrete. Methodologies for avoiding internal expansive reactions), Lisboa: Laboratório Nacional de Engenharia Civil, I.P. (LNEC). LNEC 2007b. LNEC Internal Method LABTEC 115:2007 Concrete. Determination of the sulphate, chloride and alkali content (in Portuguese), Lisboa: Laboratório Nacional de Engenharia Civil, I. P. (LNEC). LNEC 2021a. E 415:2021 Agregados para betão. Determinação da reatividade álcalis-sílica. Análise petrográfica (Aggregates for concrete. Identification of potentially alkali-silica reactive constituents. Petrographic examination) (in Portuguese), Lisboa, Portugal: LNEC - Laboratório Nacional de Engenharia Civil, I.P. LNEC 2021b. E 461:2021 Betão. Metodologias para prevenir reações químicas expansivas de origem interna (Concrete. Methodologies to prevent expansive chemical reactions of internal origin) (in Portuguese), Lisboa: Laboratório Nacional de Engenharia Civil, I.P. (LNEC). RILEM 2016a. RILEM Recommended Specification: AAR-7.1 International Specification to Minimise Damage from Alkali Reactions in Concrete. Part 1: Alkali-Silica Reaction. In: NIXON, P. J. & SIMS, I. (eds.) RILEM Recommendations for the Prevention of Damage by Alkali-Aggregate Reactions in New Concrete Structures (State-of-the-Art Report of the RILEM Technical Committee 219-ACS). Dordrecht: Springer. RILEM 2016b. RILEM Recommended Test Method: AAR-0 Outline Guide to the Use of RILEM Methods in the Assessment of the Alkali Reactivity Potential of Aggregate. In: NIXON, P. J. & SIMS, I. (eds.) RILEM Recommendations for the Prevention of Damage by Alkali Aggregate Reactions in New Concrete Structures (State-of-the-Art Report of the RILEM Technical Committee 219-ACS). Dordrecht, NL: Springer. RILEM 2016c. RILEM Recommended Test Method: AAR-1.1 Detection of Potential Alkali-Reactivity - Petrographic Examination Method. In: NIXON, P. J. & SIMS, I. (eds.) 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