MARINE DURABILITY OF 15-YEAR OLD UNCRACKED AND PRECRACKED CONCRETE MADE WITH DIFFERENT CEMENTS

Abstract

Marine durability of 15-year old uncracked and precracked concrete specimens made with ordinary portland (OPC), slag (Type A (SCA), B (SCB) and C (SCC)) and fly ash (Type B (FACB)) cements was investigated. Compressive strength, chloride ingress, corrosion of steel bars in concrete, and crack healing were evaluated. Chloride ingress and corrosion of steel bars in concrete are sequenced as OPC>FACB>SCA>SCB>SCC. Crack healing is observed for small crack widths (0. 5 mm) irrespective of the cement types. Large crack widths, such as 1. 5, 2 and 5 mm are not healed and significant loss of diameter is observed. Voids at the steel-concrete interface cause the formation of corrosion pits.