Buckling of ground based steel tanks subjected to wind and vacuum pressures considering uniform internal and external corrosion

• Published in: Thin-walled structures 2016-11, Vol.108, p.333-350
• Main Authors: Shokrzadeh, Amir R., Sohrabi, Mohammad R.
• Format: Article
• Language: English
• Subjects: Buckling; Corrosion; External pressure; Finite elements; Plates (structural members); Roofs; Steel cylindrical tanks; Tanks; Thinning; Vacuum pressure; Walls; Wind pressure
• ISSN: 0263-8231; 1879-3223
• DOI: 10.1016/j.tws.2016.09.007

Corrosion is one of the significant degradation processes, which occurs in aboveground oil storage tanks. A numerical study is performed to investigate the effects of internal and external corrosion on the buckling behavior of three steel cylindrical tanks with different height to diameter ratios, subjected to both wind and vacuum pressures. Internal corrosion is considered as a time dependent uniform thinning of the roof plate, roof supporting structure and upper part of the wall. Furthermore, the corrosion of the wall at the lower parts of the tank being in contact with residual water and sludge is analyzed. At the same manner, completely external corrosion of the roof and wall plates is considered in numerical analysis. It is found that the buckling load is markedly reduced with thinning of the shell for upper part and whole corrosion cases, irrespective of the loading condition. In addition, the buckled regions of the tanks are suddenly displaced toward the top of the shell during upper part corrosion process. Contrary to upper and whole corrosion cases, the critical load of tanks is only marginally affected by the corrosion of lower part of the wall. In the last part of this research, the analytical investigation results of a tank (TK-2047) that failed during discharge process in an oil plant are reported. •Buckling behavior of oil storage tanks subjected to internal corrosion are studied.•Buckling load and mode of failure are markedly changed during process of corrosion.•Tanks under wind are more sensitive to corrosion than tanks under vacuum load.•Whole corrosion of the wall causes greatest reduction in buckling strength of tanks.•Upper part corrosion of tanks can reduce the buckling strength suddenly and without any awareness.