1) Professor, University of Coimbra, DEC,

2) Doctor, LNEC, veiga@lnec.p


The wall coverings most commonly used in Portugal are plaster and render mortars, whether lime-based or cement-based and either traditionally made in-situ or pre-dosed. The same situation occurs in many other countries, in Europe and around the entire world.

The adequate formulations of rendering and plastering mortars for each situation depend on the climatic conditions and on the exposition to external factors, but it should also depend on the support characteristics. In fact to accomplish its functions, the mortar must be compatible with the support, which in turn has an important influence on the final characteristics of the applied mortar. Consequently, the properties determined in laboratory mortar specimens prepared in non-absorbent and non-adherent moulds are quite different from the final properties of the applied mortars on masonry supports.

Several factors influence the behaviour of the mortars applied on masonry, such as the properties of the supports, the application conditions and the adhesion conditions. The aim of the experimental research that is being carried out at the University of Coimbra, in collaboration with the University of Porto and LNEC, is to investigate how those facts related to the application on specific supports can influence the mortars behaviour. In this paper some of the results obtained until now will be presented.


Keywords: mortars, mortar characterization, support characterization