Open Journal Systems

Vertical stiffeners and internal pressure - influencing factors on distribution of meridional stresses in steel silos on discrete supports

Lyubomir A. Zdravkov



Steel silos are interesting, complicated facilities. In order to ensure unloading of whole amount of stored product by gravity, they are often placed on supporting structure. Values of stresses in joints between thin sheets and supporting frame elements are very high, which could cause local loss of stability in thin shells. Many researchers have worked on values and distribution of the meridional stresses in that joints. Their traditional approach is to divide in their minds cylindrical shell on two parts - discretely supported ring beam and continuously supported shell above it. As a result of their efforts critical height of shell Hcr and ideal position of intermediate stiffening ring on shell are determined. The scientific results are based on semi-membrane theory of Vlasov, in which influence of vertical stiffeners and internal pressure is not accounted. On other hand all steel silos are loaded with an internal pressure and majority of them have vertical stiffeners above supports. Is it possible the obtained scientific results to be applied to these silos? In a present article the author will show that stiffeners and pressure should not be ignored in an analysis.


steel silo; meridional stresses; critical height; vertical stiffeners; internal pressure

Full Text:



ANSYS, Release 17 (2016). ANSYS , Inc., Canonsburg, PA, USA.

API Standard 650 (2013). Welded Tanks for Oil Storage. Twelfth Edition. American Petroleum Institute, Washington, DC.

Calladine CR (1983). Theory of Shell Structures. Cambridge University Press, Cambridge, U.K.

EN 1991-4:2006 (2006). Eurocode 1 - Actions on structures - Part 4: Silos and tanks. European Committee for Standardization, Brussels.

EN 1993-1-6:2007 (2007). Design of steel structures - Part 1-6: Strength and Stability of Shell Structures. European Committee for Standardization, Brussels.

EN 1993-4-1:2007 (2007). Design of steel structures - Part 4-1: Silos. European Committee for Standardization, Brussels.

EN 10025-2:2004 (2004). Hot rolled products of structural steels - Part 2: Technical delivery conditions for non-alloy structural steels. European Committee for Standardization, Brussels.

EN 14015:2004 (2004). Specification for the Design and manufacture of site built, vertical, cylindrical, flat-bottomed, above ground, welded, steel tanks for the storage of liquids at ambient temperature and above. European Committee for Standardization, Brussels.

Knödel P, Ummenhofer T (2009). Silos with stepped wall thickness on local supports. Proceedings of the International Association for Shell and Spatial Structures (IASS) Symposium, Valencia.

Rotter JM (1985). Analysis and Design of Ringbeams. In: Design of Steel Bins for Storage of Bulk Solids, J. M. Rotter, ed., University of Sydney, Sydney, Australia, 164–183.

Topkaya C, Rotter JM (2011a). Ring beam stiffness criterion for column supported metal silos. ASCE Journal of Engineering Mechanics, 134, 846-853.

Topkaya C, Rotter JM (2011b). Stiffness of silo supporting ring beams resting on discrete supports. 6th International Conference on Thin-Walled Structures, Timisoara, Romania.

Topkaya C, Rotter JM (2014). Ideal location of intermediate ring stiffeners on discretely supported cylindrical shells. Journal of Engineering Mechanics, 140(4), 04013001.

Vlasov VZ (1961). Thin-walled elastic beams. National Science Foundation, Washington, DC.

Vlasov VZ (1964). General theory of shells and its applications in engineering. NASA Technical Translation, TTF-99, Washington, DC.

Zeybek Ӧ, Topkaya C, Rotter JM (2015). Strength and stiffness requirements for intermediate ring stiffeners on discretely cylindrical shells. Thin-Walled Structures, 96, 64-74.


  • There are currently no refbacks.