1) Assistant Professor, UL-Instituto Superior Técnico, DECivil – ICIST, anapinto@civil.ist.utl.pt

2) MSc Civil Engineering, UL-Instituto Superior Técnico / DECivil – ICIST, bruna.silva@ist.utl.pt

3) Technical Director, Parques de Sintra – Monte da Lua, S.A, daniel.silva@parquesdesintra.pt

4) Chairman of the Board, Parques de Sintra – Monte da Lua, S.A., antonio.lamas@parquesdesintra.pt;

Full Professor, UL-Instituto Superior Técnico/DECivil, alamas@civil.ist.utl.pt


The Moorish Castle is a fortress built in the 10-11th century on the Sintra hills, Portugal, and is part of the Cultural Landscape of Sintra, a World Heritage Site listed by UNESCO in 1995. Parques de Sintra – Monte da Lua S.A. is undertaking a conservation project to restore and preserve the Castle, which was preceded by the identification of different construction phases and materials. A thorough characterisation of the existing mortars was developed to enable the selection of compatible ones for the reinforcement of the masonry and joint filling.

The paper analyses the composition, physical properties and colour of samples of ancient mortars collected from the walls of the Moorish Castle and from the Church of São Pedro de Canaferrim. The results showed that the samples are composed of lime and siliceous sand. The aggregates used were similar to local granitic sand, in grain size distribution and in mineralogical composition. Plastering mortars showed a finer and more homogenous aggregate size than pointing or bedding mortars. The porosity and water absorption characteristics varied greatly between samples and showed no significant correlation with their type or location. The colour of the mortars from the Church and of the Castle walls differed in terms of lightness and chroma.


Keywords: Moorish Castle; masonry walls; ancient mortars; physical and colour characterisation