Petrographic analysis of concrete specimens that uses both optical microscopy and scanning electron microscopy (SEM) with backscatter electron detector and energy-dispersive X-ray spectrometer (EDS) provides a unique opportunity to obtain information on mineralogical, chemical, and microstructural features. Combining optical microscopy and SEM-EDS provides complementary information of concrete suffering from alkali silica reaction or sulfate attack. Feature relocation software enables the petrographer to identify an object of interest with one technique and confirm its identity with another, thereby using the strength of both techniques.
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