Experimental investigations on the stability of stiffened cylindrical shells of steel silos

• Steel shells with ribs are tested for their capacity due to local stability failure.
• Tests results are presented.
• Finite element method analysis is performed for similar models.
• When ribs with circumference ring are used shell loose stability in a local manner.

Owing to technological reasons the silos are frequently supported in a discrete way, usually by column heads. This kind of support causes a significant accumulation of compression meridional stresses in a cylindrical shell in support regions, which may lead to local buckling. The problem of determining shell resistance over the support region for different shapes of ribs constitutes a current research issue. One of highly preferred methods of strengthening this zone is the use of short ribs interconnected with a circumferential ring. Both the results of tests on the resistance of such shells and numerical analysis allowing to determine the course of this research are presented in this study. It has been demonstrated that the global resistance of the stiffened shells supported discretely is always much smaller from that in similar shells supported uniformly around the perimeter.