Characterization of structural byzantine mortars by thermogravimetric analysis

The mortars and 'cocciopesto' plasters were largely used in the historic bu ildings. as waterproof coverings and in the preparation of mortars, especia lly in horizontal structures. In recent ears. the necessity of restoration interventions with materials which are compatible with the masonry structur e requires a detailed study on these materials. In this study. the composit ion of a significative number of mortars of the Byzantine period in the Hag ia Sophia Basilica are investigated. They Here made of 'cocciopesto' (crush ed ceramic) and probably have a bearing function in the masonry structure. The samples are examined by particle size. infrared spectroscopy (FT-IR) an d thermogravimetric analyses (TG-DTG), both on the total sample and on the finer fraction (<63 mu m) which mostly constituted of binder. The results i ndicate slightly hydraulic mixtures made with a binder/aggregate ratio vari able in volume between 1/2 and 1/4. The mixture morphology and heterogeneit y seem to imply the use of hot lime technology that would lend themselves e s to the bearing function of the mortar (C) 1998 Elsevier Science B.V.