Factors affecting near surface tests of in-situ concrete structures for carbonation-induced corrosion.

Abstract

Corrosion in RC members leads to reduction in strength and serviceability of the structures. Several non-destructive testing techniques can be employed to evaluate the possibility of reinforcement corrosion relatively quickly and cost-effectively. However, due to uncontrollable variations of structures conditions in the field, the reliability and validity of the test results are in doubt. This paper examines the effects of surface conditions, concrete moisture content, ambient conditions, and carbonation depth on the rebound number, half-cell potential, two and four-probe resistivities, and linear polarization resistance. Eighteen reinforced concrete buildings located in Bangkok metropolitan areas which are ten years or older were sampled. Statistical analyses were performed to determine the significance of each effect on the non-destructive test values. The effects and relationship of each factor were shown on this paper.