THE MORTAR DAMAGE AND ITS HARMFUL EFFECTS ON THE GLAZED CERAMIC TILES IN TERBANA MOSQUE – ALEXANDRIA, EGYPT

Abstract

This research discusses the damaging factors of the mortar used to affix the glazed ceramic tiles on the walls of Terbana mosque (built in 1685, Ottoman period) in Alexandria, Egypt, and the extension of the damaged impact to the ceramic tiles. This famous, and particularly outstanding mosque with several suspended shops below it, is built in the Delta architectural style, with walls made of limestone blocks and a little red and black adobe for decorative work, a wooden roof and glazed ceramic tiles, with plants and geometric ornaments, adorn parts of the mosque walls. Salt content in the weather of Alexandria is relatively high; this salt is the largest contributor to the deterioration factor of Terbana mosque with varying degrees of deterioration. Impacts come in different forms; salts caused disintegration of the mortar into soft powder in some places and then pushed the outer surface of the limestone and brickwork. Where tiles have been installed in a building near the sea, they would be subject to degrees of salt deterioration, making it very difficult to prevent deterioration of the tiles or to the walls. Results from analytic methods such as scanning electron microscopy (SEM-EDX), and X-ray diffraction (XRD), reveal a high percent of crystallized salts of sodium chloride NaCl (Halite) in the fixed mortar, in the body of the tiles, and in the glaze layer on the tiles surfaces. Proposed solutions to mitigate the salts deterioration are provided.

Keywords

• terbana mosque
• salt tolerances
• delta style
• sustain cracks
• the grout
• affix
• reflective cracking
• waterproof mortar