The Analysis Of A Floor-steel Silo Under Seismic Force

Silo structure is widely used in industrial and transportation sectors,particularly in the systems of coal,building materials,metallurgy and so on.It is not perfect in seismic design for the silo structures.In the earthquakes that have occurred in our country, almost all of the silos have been varying degrees of damage.In this article the analysis is based on floor-alumina silo,using ANSYS finite element analysis software,the silo model is established,and the analysis is completed on three models,in the first one materials are full contacted with the wall of warehouse;in the another one the upper 30%is considered coupling and the lower 70%is considered contacting;in the last one coupling is the only factor to consider.A model of the silo is set up using ANSYS software for spectral analysis,and the results of the stress and displacement of the silo of three models are received,and the analysis of three models of grain silo is compared to the result calculated specifications. The normative calculation results are higher obviously than the finite element results.It is shown that the friction between the storage and silo wall and the accumulation stiffness of storage can be very good seismic energy consumptions in the process of an earthquake.Because spectral analysis does not reflect the true results of the earthquake,the transient analysis is also carded out in the paper,the time-history analysis of EL-Centro earthquake wave patterns for three models is completed,and the results are compared with the ones which are according to the norms.Time-history analysis can excellently reflect the stress and deformation of the silo structure in the process of earthquake,the time-history analysis results furtherly prove that the friction between the storage and silo wall is the factor that can not be ignored in the process of earthquake. Finally,the analysis of three kinds of load cases is completed,at the same time compared with the ones which are according to the norms,The results show that for the floor-standing steel silo under the effect of the earthquake,the earthquake played a control role in the design of the silo.The calculations show that the phenomenon of "Elephant-foot" is obvious and some stress concentrations are existing in the finite element calculation results.