nomenclature long as it for themore takes to common or visually important examine the of natural minerals that natural sample mineral makeup common aggregate minerals—an aggregates sources. aid in determining their performance To outline Visual and petrographic microscopic Usually includes ASTM C 295, examination examination of opticalmicroscopy. Also may Petrographic procedures for prepared visual include XRD analysis, examination of samples—sieve examination differential thermal analysis, aggregates for aid analysis, does not or infrared spectroscopy—see concrete indetermining microscopy, involve long ASTM C 294 for descriptive their scratch or acid test periods nomenclature. performance tests ASTM C 342, To determine Potential the potential volume ASR Mortar bars Primarily used for aggregates change of expansion of stored in at 52 weeks from Oklahoma, Kansas, 23°C (73.4°F) Nebraska, and Iowa. combinations combinations ASTM C 441, Varies: first Effectiveness To determine measurement of mineral effectiveness Mortar at 14 days, admixtures or of Pyrex glass then 1, 2, 3, Highly reactive artificial GBFS supplementary as 4, 5, 9, and aggregate may not represent inpreventing cementing over 12 months; real aggregate conditions. excessive materials in water at 37.8°C every 6 Pyrex contains alkalies. expansion of controlling (100°F) and high months after concrete due expansion relative humidity that as to alkali-silica from ASR necessary reaction To outline Short Specimens can be examined petrographic Visual ASTM C 856, duration with — examination (unmagnified) Petrographic includes stereomicroscopes,polarizing procedures for and microscopic examination of preparation microscopes, hardened examination of hardened of samples metallographic microscopes, prepared concrete and and scanning electron in samples and microscope. determining
of natural mineral aggregates nomenclature for themore common or important natural minerals—an aid in determining their performance long as it takes to visually examine the sample minerals that makeup common aggregate sources. ASTM C 295, Petrographic examination of aggregates for concrete To outline petrographic examination procedures for aid indetermining their performance Visual and microscopic examination of prepared samples—sieve analysis, microscopy, scratch or acid tests examination does not involve long test periods Usually includes opticalmicroscopy. Also may include XRD analysis, differential thermal analysis, or infrared spectroscopy—see ASTM C 294 for descriptive nomenclature. ASTM C 342, Potential volume change of combinations To determine the potential ASR expansion of combinations Mortar bars stored in at 23°C (73.4°F) 52 weeks Primarily used for aggregates from Oklahoma, Kansas, Nebraska, and Iowa. ASTM C 441, Effectiveness of mineral admixtures or GBFS inpreventing excessive expansion of concrete due to alkali-silica reaction To determine effectiveness of supplementary cementing materials in controlling expansion from ASR Mortar Pyrex glass as over water at 37.8°C (100°F) and high relative humidity Varies: first measurement at 14 days, then 1, 2, 3, 4, 5, 9, and 12 months; every 6 months after that as necessary Highly reactive artificial aggregate may not represent real aggregate conditions. Pyrex contains alkalies. ASTM C 856, Petrographic examination of hardened concrete To outline petrographic examination procedures for hardened in determining Visual (unmagnified) and microscopic examination of prepared samples Short duration — includes preparation of samples and visual and Specimens can be examined with stereomicroscopes,polarizing microscopes, metallographic microscopes, and scanning electron microscope.
document_alkali_silica_reactions.docx