Investigation of buckling behavior of thin-walled steel tanks with dents and corrosion

Thin-walled steel structures, known for their high strength-to-weight ratios, are highly susceptible to damage caused by mechanical and chemical factors. The chemical reactions occurring in such structures can lead to accelerated degradation due to their limited thickness, leaving them particularly vulnerable to the effects of corrosion. This study investigates the combined effects of corrosion and dents on the buckling capacity of thin-walled cylindrical steel tanks fabricated from 0.45 mm thick steel sheets. The specimens were precisely manufactured to achieve an r/t ratio of 445, ensuring realistic structural behavior. The study particularly focused on the chemical interactions resulting from corrosion induced by 2.5% and 5% hydrochloric acid solutions. This corrosion led to oxidation, material loss, and ultimately, changes in the stability and strength of the material. To simulate mechanical imperfections, dents with depths equal to one, two, and three times the shell thickness were applied. Additionally, the experimental results obtained in this study were compared with theoretical formulations and a previous study from the literature to evaluate the accuracy and applicability of these approaches. The findings revealed that both corrosion and dents significantly reduced the buckling capacity of the steel shells, highlighting the critical role of these combined factors in influencing structural performance.