Median diameter as a grading characteristic for fine aggregate cement composite designing

More and more cement composites produced all over the world are based on fine aggregates due to lack of locally available coarse aggregate. Presently there is no universally used grading characteristic of fine aggregate useful for concrete and mortar designing. This study is aimed at developing a technic for describing natural fine aggregates using a single but reliable factor. In the author’s opinion the median grain diameter dm is a suitable factor for describing grading of fine aggregate which has a physical meaning. The analysis performed on the basis of 65 documented and described aggregate pit deposits in Pomerania region in Poland proved that there is a strong correlation between median grain diameter dm, fineness modulus and specific surface.