Ashkan KhodaBandehLou - Doctor of philosophy of Technical sciense, Faculty of Engineering ,Civil Engineering ، Department,Urmia Branch, Islamic Azad University, Urmia, Iran
Masoud sabzchi - M.A.Student o structure, Faculty of Engineering ,Civil Engineering Department,Urmia Branch, Islamic Azad University, Urmia, Iran

Since a lot of important and noticeable behaviors of concrete in Nano dimensions and scales form with source of its micro structure ,Nano technology can has a crucial role in understanding and studying better performance and improving concrete micro structure as a Nano- material. In the present study, in order to achieve high performance and high strength concrete, and use in resistant structures and increasing the durability, the Nano silica is used. Based on the obtained results of compressive strength, mechanical properties of Nano-material concretes are compared with control samples (with no Nano-material). The results showed that these concretes can be regarded in high performance and high resistant concrete, HPHSC. To study permeability of this concrete, microscopic studies (SEM)of different ages for Pozzolan and control samples are done and it is referred to the obtained results.

Nano-Silica, Permeability, Mechanical properties, Microscopic studies