Employing spatial, hybrid and amplitude roughness parameters for unveiling the surface roughness features of mineral and organic admixtures

Scanning electron microscopy (SEM) permits to evaluate the surface morphology and surface roughness of pozzolans and admixtures. The field of mineral and organic admixtures has considerable interest in using SEM. However, several challenges are encountered which hamper the precision of quantitative roughness evaluation of mineral and organic admixtures using SEM and these challenges are usually bypassed in literature. In this research, surface roughness properties of pozzolans and admixtures were analysed from six perspectives: spatial parameters, hybrid parameters, amplitude parameters, surface roughness profiles, bearing ratio curves (BRCs) and amplitude density functions (ADFs). The generated roughness characteristics provided detailed information of roughness properties of the pozzolans and admixtures in a time efficient and cost effective way, which is usually very hard to achieve using experimental works. The comparisons of the obtained roughness data for the specimens showed considerable agreement with the roughness profiles and verified the interpretation of the established roughness profiles. Using the ADFs and BRCs for evaluating heights of the roughness profiles provided significant data encapsulated in the shapes of ADFs and BRCs. Moreover, the interpretation of the transformed logarithmic profiles seemed to have nearly retained similar meanings with the conventional profiles, although their scrutiny was observed to be complex. With brand new discussions on spatial, hybrid and amplitude parameters of mineral and organic admixtures, this research is a step forward in characterisation of roughness parameters of mineral and organic admixtures. This study expands the characterisation of pozzolans and admixtures, highlighting significant parameters to be considered in the application of mineral and organic admixtures.