Accelerated corrosion tests were performed on ten specimens which are designed as elements cut from RC columns in order to investigate cracking behaviors and increasing strains of bars due to chloride attack. The variable factors are concrete strength, longitudinal and transverse bar arrangement, and covering depth. Test results indicated that a corrosion cracking is most early appeared on the surface above transverse bars of the specimens having lower concrete strength and thinner cover, and that corrosion cracking behaviors greatly depend on concrete strength, namely, pore structures in the cement paste. An ultrasonic inspection can early detect damage around corroding bars.
