The gypsum mortars with different types of aggregate were studied. The surface roughness of fine aggregates and the fracture surface roughness were evaluated by a confocal laser scanning microscopy. Four gypsum mortars and one gypsum paste were tested. The results from the confocal laser scanning microscopy (CLSM) are compared with the pictures of grain surface taken by a scanning electron microscopy (SEM) and both methods seem to be appropriate for surface evaluation. The influence of the surface aggregate roughness on some gypsum mortar properties is demonstrated.
A geometric model for fatigue crack closure induced by fracture surface roughness