Cracks of corrosive reinforced concrete beams

The character of cracks is an important index for estimating the serviceability limit state of the reinforced concrete(RC)structure.37 RC beams with different reinforced bar types and ratio of reinforced were made in the laboratory.The stage of accelerated corrosion was achieved by impressing direct current on the reinforced bars.The corrosion ratio was controlled by the electric intensity and the electric passing time.The cracking process and the characteristic of cracks in the static load test are discussed.Based on the comparative analysis to the calculated results specified in the code for design of highway reinforced concrete and prestressed concrete bridges and culverts(CDHRCPCBC) JTG D62-2004 and Code for design of concrete structures(CDCS) GB 500102002,the relationship between the corrosion ratio and average spacing of reinforced concrete is established,and the relationship between the corrosion ratio and the crack width is also given.All the results indicate when the corrosion ratio is small,the character of cracks of the reinforced concrete bending members is the same as that of members without corrosion;however,when the corrosion ratio is large,both the spacing and the width of the crack are increased.The models can be used for evaluation of the flexural strength of corrosive RC members.