عنوان مقاله [English]
In this research, in order to evaluate the effect of parameters such as geometry, stored material, concrete strength, silo wall thickness and FE mesh size on seismic response modification factor, finite element modeling is generated in three conditions: full, half-filled and empty. In this way finite element Abaqus is used for modeling and static nonlinear pushover analysis. As a sample, two types of models are created: the clinker silo (without basis) and by pass clinker silo (legged). Then, the mentioned models are subjected to nonlinear finite element method and the base shear-displacement diagrams are extracted. All of the mentioned graphs are evaluated by Young method to be bilinear. The response modification factor and the connected parameters such as plasticity, added resistance and plasticity ratio have been calculated.
The calculated response factors are more than that of the design regulation of seismic buildings code (standard of 2800) and also the Code of IBC (Asce-7-16) and it can be said that regulations are conservative.
The results show that the parameters of the geometry (diameter to height) and filled or emptiness of the silos are not very effective in the amount of response modification factor. However, the response behavior factor does not change significantly by increasing the strength of the concrete and it can be concluded that the response factor is not related to the concrete strength.
Increasing the thickness of the silos due to increased plastic capacity increases the R Value and increasing the mesh size due to the reduction of the accuracy of the calculations, reduces R and it indicates that the change of the response factor obtained from the initial value is small and does not affect the behavior much.