163y Investigation of Corrosion of Reinforcement Concrete with Different Pozzolans in the Sour System

Ehsan Bakhshi, National Petrochemical Company, Tehran, Iran and Fatemeh Abniki, National Petrochemical Company,Ghadir Group, Tehran, Iran.

The durability of concrete in a corrosive ambient has been very important and a concern for industrial aspects.. Natural and artificial pozzolans in replacement with cement have performed very well in concrete structures situated in such environments. In order to investigate the performance of pozzolanic cements, concrete specimens incorporating Type 2, tof, pamise and silica fume cements have made and maintained in a simulated one sour lake water condition( free air, submerged and wetting-drying) and a standard curing of 4 months. All the considered mixtures have been made with two different water-cement ratios (0.4 and 0.45).Three sizes of concrete cover (2, 3.5 ,5 cm) have been considered for every specimen in each mixture. Some parameters have been tested, such as the corrosion potential measurement, electrical resistivity and compressive strength, have been carried out at different ages. Results show that the wetting-drying condition has had a great influence on the durability of the concretes. Pozzolanic cements have shown better performance compared to the Type 2 cement, while the silica fume concrete showed the best performance . The use of a 450 kg/cubic meter cement and water –cement ratio less than 0.4, had a great influence on the prevention of the permeation of corrosive ions into concretes and thus their durability enhancement.