MULTISCIENTIFIC-BASED APPROACH TO DIAGNOSIS AND CHARACTERIZATION OF HISTORIC STONE-MASONRY WALLS: THE MAUSOLEUM OF AL-IMAM AL-SHAFI'I, CAIRO (EGYPT)

The purpose of this research is to carry out a scientific-based characterization of one of the most important historic masonry building in Egypt, the mausoleum of al-Imam al-Shafi’I, which is considered one of the few buildings still surviving dated to Ayyubid period (13th century). The study aims at determining not only the characteristics of the building materials’ components, their relative proportions and morphological features, but also the causes of damage, decay and alteration phenomena occurred, in order to relate the structural and mechanical behavior of the construction materials depending on their compositional and microstructural nature and finally to set-up proper restorations protocols. Comprehensive studies have been implemented on stone masonry walls through an interdisciplinary procedure including in-situ investigations, and experimental testing on extracted core-samples together with the updated measurements and documentations of the current state of the mausoleum. The followed integrated diagnostic approach based upon field survey data allowed the identification of the mineralogical characteristics, fabric morphology, physical and mechanical properties of the construction materials including limestone and lime-based mortars of the inner and outer leaves of the stone-masonry walls, which give very important information for conservation and restoration strategies. Methods employed included X-Ray diffraction (XRD), scanning electron microscopy (SEM-EDX), petrographic microscopy and thin sections