Crushed Brick / Lime Mortars of Justinian's Hagia Sophia

Abstract

ABSTRACTStructural studies to determine the earthquake worthiness of Hagia Sophia in Istanbul have proved that the monument's static and dynamic behavior depends very strongly on the mechanical and chemical properties of these mortars and bricks used in its masonry. So, the cementrtious nature of the mortars not only explains the fact that the monument still stands but also the very large static deformations which it has undergone, since such mortars have a very long curig period from one to two years. According to the analysis of the dynamic data, the strong motion data from a 4.8R magnitude earthquake about 120 Km south of the building was used to determine the first three natural frequencies of the building. These results show a decrease of about 5–10% in the natural frequencies, as the amplitude of the accelerations increases and returns to their initial values, due to the non-linear nature of the masonry. The above mentioned behavior allows the structure to absorb energy without effecting its material properties, irreversibly. The properties of the mortars and bricks leaded to an extensive study, employing several experimental techniques (FOM, OM, XRD, SEM, TEM, TG/DTA). The results indicated mortars with considerable mechanical strength along with longevity. The model used proved to be resistant to the environmental pollution and to the presence of sah, while the gel phase as binder allows for greater energy absorption and the compatibility of the mortar to the original ones allows continuous stresses and strains. Hence, the recreation of the Hagia Sophia is attempted through a reverse engineering approach to simulate the historical mortars.