The role of aggregate and binder content in the physical and mechanical properties of mortars from historical rubble stone masonry walls of the National Palace of Sintra

Abstract

The relevant role of mortars for the structural behavior of historical rubble stone masonry and the scarce information available justifies the research on these materials. Mortars collected from several masonry structures of the National Palace of Sintra (Portugal), built across different centuries, were examined in situ and in laboratory. The influence of b:a ratio, pore structure, aggregate and binder attributes on the mortars properties is discussed. The results led to purpose drilling resistance and modified Schmidt hammer to assess and distinguish the mortars quality from a mechanical point of view based on their hardness and drilling strength. Moreover, a contribution is provided to estimate a possible order of magnitude of rebound values and drilling resistance with respect to the binder content for similar mortars.