An investigation on the durability of building materials due to weathering agents

The durability of rocks under severe and variable climatic conditions is a determining factor in the stability of natural stone structures used in buildings or sculpture. Freeze–thaw and salt crystallization are of the most powerful weathering agents on the durability of building stones. In this study, the effect these agents on 14 different building stones were investigated using ageing tests. Moreover, for estimation of stone durability against freeze-thaw, effective porosity and mechanical properties (Brazilian tensile strength, point load index and P-wave velocity) were used. In order to investigate the effect of salt solutions on the samples, salt crystallization test in sodium and magnesium sulfate was performed. The results showed that with the increase of freeze-thaw cycles, the values of mechanical properties were decreased. Moreover, the samples with more effective porosity and less mechanical properties had less durability against freeze–thaw. Accordingly, the most suitable stones for facade cladding of the buildings were recommended.