Introduction of large-scale durability device and its applicability for evaluating hard rocks durability

One of the most important issues in the design and implementation of engineering structures is to evaluate and investigate their durability against processes of consecutive wear، wet and dry. The durability of rock is resistance against chemical and physical weathering، the shape، size and status of the initial appearance in a long time and environmental conditions prevailing in the rock، hence it is important to evaluate the durability of rock. Since the device of standard durability (Franklin & Chandra، 1972) designed to evaluate and investigate durability of soft and argillites rocks. So، appears to be essential to design a durability device، which can evaluate hard rocks. For this purpose، Researchers of the Department of Geological Engineering، Tarbiat Modares University، durability device as «large-scale durability device» was designed and built which the length and diameter of the device، is 6 and 4. 3 times standard durability device، respectively، and needs 10 samples with weight of 400 to 600 g. In order to investigation the applicability of this device for hard rocks durability، we selected 17 building rocks samples of the igneous، sedimentary، metamorphic and pyroclastic rocks. Then their mineralogical، physical and mechanical properties were investigated. More، experiments of standard and large-scale durability up to 15 cycles were performed and data obtained were analyzed. The results show that، the large-scale durability device than standard durability، have more applicability for evaluating the durability of hard rocks.