Abstract
The seismic design of industrial flat-bottom ground-supported silos filled with granular material still presents several challenges to be addressed. They are related to the main aspects which differentiate silo structures containing granular material from other civil structural typologies: 1) the relatively low silo structure mass as compared to the ensiled content mass; 2) the granular nature of the ensiled material. Indeed, the internal actions in the structural members are governed by the complex dynamic interactions along the interfaces between granular content and silo wall or base, or even the internal interaction between particles. More in detail, even though the scientific interest in such complex interactions dates back to the middle of the 19th century, several issues are still unclear such as the dependency of the fundamental dynamic properties (period of vibration and damping ratio) on the characteristics of the dynamic excitation (intensity, frequency content, duration) or the amount of ensiled material mass activated during a seismic excitation and provoking extra pressures on the wall (effective mass). Therefore, most of current seismic code provisions for silos are grounded on rather approximate and simplified assumptions leading to often over-conservative evaluations. The present paper intends to provide a comprehensive summary of the mainly acknowledged experimental and theoretical advances in the dynamic and seismic behavior of silos, supporting the potential researcher in the field to understand the real differences between the code assumptions and recommendations and the actual conditions, as well as illustrating the open issues to be still further investigated.
Highlights
Storage containers of bulk material are known as bins, silos or even bunkers
The type of granular material has to be clearly specified in the design phase, since its mechanical properties strongly affect both the static and the dynamic behavior of the filled silo system and the choice of the more appropriate wall section
The findings showed that the particle-wall friction influences the wall base overturning moment and the effective mass for the squat silo is considerably lower than 80%
Summary
Storage containers of bulk material are known as bins (or grain bins), silos or even bunkers. The structural response of storage units filled with granular solid, in static but in dynamic conditions, is strongly affected by the not fully understood interaction between the structural elements and the stored content particles This aspect is especially important for steel silos characterized by a very low self-weight with respect to the stored material. The fundamental period (or, equivalently, the fundamental frequency) corresponding to the first mode of vibration of the filled silo system, due to uncertainties concerning both the above-mentioned effective mass and the lateral stiffness provided by the ensiled material Both aspects are of central importance for the evaluation of the earthquake actions since, in practice, the seismic design of silos is generally conducted by means of equivalent static analysis. ELF, Equivalent Lateral Force; MRS, Modal Response Spectrum; NLS, Non-Linear Static; NLTH, Non-Linear Time History
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
