Investigation of Engineering Properties of some samples from Building Stones in Cycles of Freeze- thaw

Rocks are natural materials which are used in a variety of engineering constructions, especially in buildings. Freeze-thaw is one of the most important environmental agents which causes change in the engineering properties, strength and durability span of rocks. In this study 14 samples of building stones with different origins were selected, then freeze-thaw test up to 30 cycles were performed and values the engineering properties of these rocks including Brazilian tensile strength, point load strength index and P-wave velocity, after every 5 cycles were determined. Results show that with increasing freeze-thaw cycles, the values of these properties have been decreased. Also, samples which had the effective porosity more than 1%, their Brazilin tensile strength, point load strength index and P-wave velocity have been more decreased.