Investigation of corrosion-induced cracks using corrosion products quantified by an X-ray technique and FE analysis of single- and multiple-rebar beams
Zhejun Xu, Mitsuyoshi Akiyama, Sopokhem Lim, Supasit Srivaranun, Dan M. Frangopol, Shinichi MIYAZATO, Ao Li
Abstract
The effects of corrosion methods, galvanostatic (GS) vs. artificial climate environment (ACE), on the relationships between corrosion products and corrosion cracks of corroded reinforced concrete beams are investigated. The experimental results show that the GS method induces smaller corrosion crack width. A novel quantitative detection method of corrosion product thickness using X-ray and digital image processing techniques is proposed for investigating the continuous development of corrosion products. As the corrosion level increases, a smaller steel-to-rust volume expansion ratio caused by continuous leakage and a lower oxidation degree of corrosion products for the GS specimens are the major reasons for the smaller corrosion cracks. Regarding the effect of rebar arrangement on the development of corrosion-induced cracks, the expansion stress from corner-located rebars restrained the growth of corrosion products and further limited the propagation of corrosion-induced cracks of the center rebar. Estimated corrosion crack width via FE analysis using measured corrosion products as input show good agreement with experimental results. • Artificial climate environment results in larger crack width than galvanostatic method. • Corrosion product thickness is quantified in the cross-section and longitudinal direction. • Mechanism of corrosion cracks is explained using spatial corrosion products in two directions. • Using corrosion products measured from X-ray images better predict crack widths in FE analysis. • FE analysis considering spatial steel corrosion can well predict the loading capacity of RC beams.