A new approach to the characterisation of particle shape and surface properties of powders employed in concrete industry

Development of high-performance and versatile cement-based materials like self-compacting concrete (SCC) and reactive powder concrete (RPC) has increased the research on inert and semi-inert powders. Today, the characterisation of these materials is an emergent subject. In this study, a new and practical approach to characterise the particle shape and surface morphology of ground materials has been proposed. For this purpose, two types of powders (limestone and quartz) at two different particle size distributions (PSD) were prepared by grinding. SEM images of these fine materials were analysed by using some conventional commands of image analysis. Possible quantification methods of shape characteristics and surface roughness of fillers were proposed. The results showed that, in addition to PSD; particle shape and surface morphology of ground materials can be quantitatively determined. Success of characterisation significantly depends on preparation of appropriate and representative SEM images. The accurate preparation of samples and proper selection of methodology of analysis is mandatory. In particular, the particle concentration in image area and magnitude of magnification play significant role on the success of analysis.