Investigation of discrepancy between tuff used as building stones in historical and modern buildings in western Turkey

Tuffs located around the town of Alacati, Turkey have been used in building construction for many years in the past. Recently, based on the efforts of the local government to develop a unique identity for the town, this practice is re-initiated. After about five years from construction, tuff used in newly constructed buildings started to show signs of deterioration. Even though tuff used in recent and older buildings in the town appeared to be the same to the naked eye, a similar deterioration has not been observed in the buildings constructed in the past (some are more than 100 years old). A previous research study has documented the suitability of tuff used in new constructions but the reasons for the discrepancy between the tuffs used in construction of the older and newer buildings has not been previously investigated. In this study the different field performances of tuffs used for historical and modern buildings were investigated against deterioration in the same environment based on the material properties and their durability. This comparison showed that the mineralogical composition and amount of clay contents of the tuffs were one of the major factors resulting in difference in deterioration and durability rates of the tuffs used in building construction within the region. (C) 2015 Elsevier Ltd. All rights reserved

Effects of different drying temperatures on the physical and mechanical properties of some marbles (Muğla, Turkey) during salt crystallization tests

This study aims to understand the effects of drying temperatures during sodium sulphate salt crystallization tests on the physico-mechanical properties of some Mug. la marbles. Four commercially available and extensively used Turkish marbles, namely Mug. la white, Milas white, Derebag white and Milas Pearl, having different textural properties were subjected to sodium sulphate salt crystallization tests with 30, 60 and 100 degrees C drying temperatures. The change in the physico-mechanical properties of the marbles including weight, dry and saturated unit weights, water absorption, effective porosity, dry and saturated sonic velocities and dry uniaxial compressive strength has been determined for various stages of the salt crystallization tests. The results were evaluated in terms of drying temperatures and the textural properties of the marbles. Based on the test results, the salt crystallization with the drying temperature of 100 degrees C causes significant damage to all marbles. However, the drying temperature of the test at 60 degrees C gives rise to moderate damage, whereas the drying of the marbles at 30 degrees C gives the least damage. Therefore, the drying temperature of the salt crystallization tests should be less than 60 degrees C and preferably around 30 degrees C in order to avoid additional thermal effects on marbles. Furthermore, the fine-gained Milas pearl marble with irregular grain boundary is found to be the most resistant one against the salt crystallization