Abstract:

This paper presents the consolidation of the Şirinçavuş and Karamursel volcanic tuffs which were widely used in Dolmabahçe Palace. The research on the consolidation of the volcanic tuffs was based on a longterm experimental programme. The first treatments were with a methyl acrylate and ethyl metacrylate copolymer+water repellent. The untreated samples were characterized and their deterioration processes and morphologies were detected by SEM-EDXA and ICP. The efficacy of the treatment was controlled by the comparison of the results of the tests which were conducted to determine the physical properties of the untreated and treated samples. The results seemed to be unsatisfactory. The research was continued by water repellent impregnations to prove the theory on the conservation of volcanic tuffs with total surface protection which claimed a better performance over consolidant+water repellent treatments. The treatments which silane-siloxane micro emulsions gave promising results. Further work was continued on different volcanic tuff which was quarried from Yalova-Karamursel region and was subjected to similar deterioration medium which had sea spray and air pollution as major decay causes. The samples were characterized by tests for the determination of the physical, petrographic properties and mineral composition. Consecutively they were treated with a consolidant+water repellent and a water repellent on its own. The improvement in physical properties, the deposition and the settlement of the polymer films in the pores by means of Mercury Intrusion, X-Ray Diffraction Analysis, SEM-EDS were detected. Artificial ageing tests such as salt crystallisation and freeze-thaw cycles were conducted to clarify the protective effect of the overmentioned impregnations. In this case the results proved the opposite of the theory on the efficacy of the total surface protection by water repellents on their own

Keywords: