Interactive Buckling Tests on Cylinders Subjected to External Pressure and Axial Compression

Abstract

The results of 40 buckling tests on unstiffened welded steel cylindrical shells subjected to combined axial compression and external lateral pressure are compared in the paper with the predictions of theory and various Codes (ASME III, DnV and ECCS). The radius/thickness ratios of the models tested were R/t ≈ 100 and 300 and the length/radius ratios covered the range 0.18 < L/R < 1.45. Three interaction equations were studied, viz. a linear, a quadratic and a linear/quadratic equation suggested recently by Odland. Best agreement with experiment was obtained using the quadratic equation in conjunction with the DnV or ASME III Codes. The ECCS predictions of buckling stress were safe but were more conservative than the other two Codes. Some interactive buckling tests on ring-stiffened cylinders (and conducted recently by other workers) were also compared with the predictions of the above three Codes. The agreement between predicted buckling stresses and test results was broadly similar to that found for the Liverpool models. For very short unstiffened and ring-stiffened cylindrical shells, the theoretical interaction curves were a little unusual. In addition, the test results for external lateral pressure alone on these shells, and obtained by different research groups, did not all agree.