Assessment of Individual ASR-Aggregate Particles by XRD
This article describes the direct analysis of polished individual aggregate particles by X-ray diffraction (XRD), as compared to traditional powder samples. These particles are selected from mortar bars and concrete prisms previously exposed to expansion testing as well as virgin aggregate from the PARTNER project .The authors performed XRD analyses in solid and powder samples of the same aggregate particle. Comparing the results was concluded that for fine grained rocks without preferred orientation the use of a slab sample is more time efficient than traditional powder specimen, without compromising accuracy. Another advantage of this approach is that the investigated aggregate particles can be selected based on petrographic observations done in concrete thin sections affected by alkali-silica reaction (ASR).
KeywordsAggregates for concrete Alkali-silica reaction (ASR) X-ray diffraction (XRD) Silica polymorphs
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The first author kindly acknowledges financial support from Fundação para a Ciência e Tecnologia (FTC/Portugal) through doctoral grant reference SFRH/BD/41810/2007.
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