DURABILITY ENHANCEMENT OF RC STRUCTURES COVERED WITH A DENSE LAYER FORMED BY MARINE AQUATIC FOULING ORGANISMS

Abstract

Marine aquatic fouling organisms form a dence layer on the surface of concrete structures and enhance durability against corrosion of reinforcement bars. The reason is that a surface layer formed by these organisms restrains penetration of chloride ions and oxygen into concrete and controls corrosion of reinforcement steel. The less OH^- concentration of pore solution is and the more the volume of pore is, the more the layer is. The concept of durability assessment based on prediction of chloride ions penetration and corrosion progress and the metod of utilization of this layer for durability improvement are also shown in this paper.