STUDY ON A DETERIORATION AND DETERIORATION INDICATOR OF CONCRETE UNDER MARINE ENVIRONMENTS

In order to investigate the deterioration of concrete under marine environments, both concrete cores sampled from existing structures and test specimens exposed in the outdoor pool of natural seawater were examined by Vickers hardness test, EPMA and Cl penetration and carbonation depth measurements. Correlation analysis for the distributions of various elements was carried out and following interesting behaviors were observed: 1) The depth of maximum Mg2+ concentration was correlated with the carbonation depth. 2) Deteriorated areas in concrete specimens based on Vickers hardness were correlated with the penetration depth of Mg2+. This result means that the penetration depth of Mg2+ can be a simple indicator of concrete deterioration under marine environments.