Published online by Cambridge University Press: 21 February 2011
Particle size distributions of a suite of fly ashes previously analyzed by aclassical sedimentary proced ure have been redetermined using a commercial laser-based particle size measurement system. For most of the fly ashes the concordance between the two sets of data was unexpectedly close, considering the different physical principles involved in the two types of measurement. Laser diffraction instruments (“laser sizers”) appear to have the potential for extremely rapid and accurate size distribution measurement for fly ashes to be used in commercial applications. Such determinations, easily carried out on a routine basis, could serve as important elements in future specifications for acceptance and quality assurance programs.