Grain characteristics and engineering properties of coal ash

Abstract Ash produced by the coal fired thermal plants is often used as a geo-material where its characteristics and mechanical behavior is important. The present study describes an investigation into the grain characteristics and the engineering properties of coal ash. The results of x-ray diffraction, micrographic observation and grain size distribution are analyzed in relation to maximum and minimum void ratio, permeability, compressibility and frictional properties. The grain size is found to be a significant grain characteristic that may be used for classification of ash as well as interpretation of primary, secondary and index properties. The compressibility and frictional characteristics depend on stress environment and packing with respect to a critical state uniquely identified by material characteristics. The fitting parameters for the selected sets of samples have been evaluated for the Ropar coal ash. This study presents the data and the correlations that are pertinent to a wider community of geo-technical and geo-environmental engineers interested in the utilization of coal ash as a structural fill.