Effectiveness Assessment of Nano Silicate Application to Improve Mechanical Properties of a Limestone Used in the Architecture of Pasargadae World Heritage Site

In this study, according to the high value of stone architecture in Iran, an investigation to improve mechanical properties on a type of limestone (Sandy limestone) used in Pasargadae were done by Nano Silicate (SiO2) as a consolidation material. Thus, some mechanical properties such as water absorption, water vapor permeability, porosity and resistance to against aging tests have studied by using UNE-EN standards and Ultrasonic velocity as well as changes in superficial strength by Micro-drilling. Results show the rate of water absorption and water drying decrease about %11 and water capillarity slightly changed. In contrast, water vapor permeability remained almost the same. But, the porosity of stone decreased %14 as well as %20 increasing the superficial resistance. Hence the improving two properties of the stone (porosity and superficial resistance) by applying Nano Silicate are the advantages of this kind of material in order to increase sandy limestone durability used at Pasargadae World Heritage Site.