Abstract
Cement, one of the basic materials of construction engineering, has an important place in view of strength and cost of structure. Cement consumption is increasing parallel to development of building construction sector. For cement producer, minimal cost is desired by using new and economical material source. On the other hand, the controllers and contractors need cheaper, safer and higher strength materials. It is well known that pozzolanics are chemically active silica and alumina bearing materials. There are many different pozzolanic materials. In this study, the volcanic slags from Kula and Gokccoren in Turkey were used as cement additives. The Portland cement clinker and slag were ground together. Normal Portland cement mortar and slag cement mortar were made with a constant water/binder ratio and similar type aggregates. In each slag cement mortar, the slag was 25 percent by weight of cement. The experimental results show that there is a good linear correlation between the Blaine fineness of cement and strengths of mortar. As the fineness of volcanic slag cement increases, the interfacial zone between aggregate and cement paste becomes stronger, as a result both compressive strength increase