Investigation of the Effect of Grain Size on the Strength of Composite Mortars Produced Using Polyester Matrix and Stone Powder for the Restoration of Historical Buildings Built with Nevsehir Stones

Nevsehir stone is a stone unique to the pyroclastic rock type, quarried from the Nevsehir province in the Central Anatolia Region of Turkey. This stone is a material used in the construction of historical buildings and today's modern buildings. Buildings; neglect, water, humidity, natural disasters, etc. it loses its strength over time due to environmental and atmospheric factors. Failure to take precautions against such damage problems, especially in historical buildings, causes the buildings to collapse and the number of historical buildings today to gradually decrease. In order to solve this problem, since the types of stone materials in buildings vary from country to country, it is necessary to develop composite mortars according to the properties of the materials and to know the properties of these mortars. In this study, it was aimed to develop polyester matrix and stone powder based composite mortars for the restoration of historical buildings built with Nevsehir stones and to examine the effect of grain size in these mortars on their strength. While Nevsehir stone is used in buildings, it is cut into certain sizes and stone powder is formed during the cutting process. For this reason, different mixtures were prepared to determine the strength properties of the grain sizes of stone powders in composite mortar mixtures, and the mechanical and hydrophilic properties of these composite mortars were determined. Among the composite mortars, the most suitable mortar has a grain size between 150–250 μm and was prepared by using 35% polyester matrix and 65% stone powder wt. Additionally, as a result of the experiments; it was determined that this composite mortar provided a significant increase in the strength and surface contact angle of Nevsehir stone. Therefore, it was concluded that polyester matrix mortar contributed to the protection of historical buildings built with Nevsehir stone.