Shaking table tests on a small-scale steel cylindrical silo model in different filling conditions

Abstract

In this paper, to study the dynamic response and energy dissipation capacity, a series of shaking table tests on a small-scale cylindrical steel silo structure model was proposed. Meanwhile, to investigate the interaction law of the wheat material and steel silo structure system, the granular material-structure interaction was also considered. Three models with different steel silo filling conditions were investigated, which were empty silo (ES), half wheat (HW) and full wheat (FW) respectively. The earthquake excitations of the 1940 El-Centro earthquake (El), the 1952 Taft earthquake (TF), and an artificial wave (AW) were selected and used in the shaking table tests. Results indicate that the fundamental frequency of the FW model was decreased by 19.70% on average compared to the HW model. However, the damping ratio of the HW model was larger due to the large dynamic response. Especially, ES, HW and FW models showed different acceleration vertical profiles due to different filling states. The FW model had a smaller dynamic response of the silo structure than HW model, because its acceleration magnification factors at the silo wall and inside the wheat material were smaller. At the same time, the friction, collision, and interaction among wheat particles and between wheat particles and silos rendered HW and FW models a stronger energy dissipation capacity than the ES model under the three earthquake excitations. In addition, there existed a clear phase difference between the acceleration response of the stored wheat and steel silo under earthquake excitation, suggesting the asynchrony movement between the stored wheat and silo. Finally, the storage-silo acceleration correlation which could be used to quantitatively describe the degree of interaction between the granular material and silo was also proposed.