Simulation Study On Seismic Response,Static Lateral Pressure,and Dynamic Lateral Pressure Of Steel Silo With Stored Materials

As a spatially thin shell structure,steel silo has various forms of storage materials stored inside,and the mechanical properties of different storage materials are very different.The complex mechanical properties of steel silos result not only from their own structure,but also from the uncertainty of the action of the stored material on the silo body.The force of the storage material on the silo body under earthquake is the main factor leading to buckling damage and even collapse of the silo,and there is also a complex mutual coupling effect between them.Based on this situation,this paper takes the floor-type steel silo as the research object,with the combination of finite element numerical simulation and theoretical analysis,and studies the dynamic response,interaction mechanism and the distribution of static and dynamic lateral pressure of the storage material-steel silo structural system,the main research contents and results are as follows:(1)The three-dimensional finite element numerical model was developed using ABAQUS finite element software to take into account the bulk-solid coupling effect.The mechanical behaviour of the silo is described by the hypoplastic constitutive model,and the Coulomb friction model is used for the master-slave contact between the silo and the storage material.The reasonableness and reliability of the modelling method is verified by comparison with the shaking table test of the real silo model.(2)The effects of silo height-to-diameter ratio,grain loading height and input peak ground acceleration(PGA)on the dynamic response of the storage material to the silo body and the structural energy dissipation characteristics were investigated.The results show that the acceleration response of the silo wall is gradually increased by the addition of the storage material under small earthquakes,and the acceleration response of the silo wall at the same height is more influenced by the storage material under large earthquakes.The relative peak displacement of the silo increases with the increase of the silo height-to-diameter ratio,grain loading height and PGA.The increased filling capacity of the storage material increases the energy dissipation capacity of the storage material-steel silo system under seismic action.(3)The dynamic interaction between the storage material and the silo body was quantified by the storage material-silo acceleration correlation(SSAC).The results show that there is a boundary position for the interaction between the storage material and the silo body under seismic action,the closer to the top,the more intense the interaction between them.With the increase of height-to-diameter ratio and input peak ground acceleration,the storage material at the top tends to flow under stronger seismic excitation,and the interaction with the silo body is more obvious.The degree of dynamic interaction between them is more affected by the material parameters of the storage material in the silo.(4)Numerical simulations were carried out for the static lateral pressure of the storage material under the self-weight of the structure and the dynamic lateral pressure of the storage material under the seismic action,which were compared with the Chinese and European codes.The results show that the increase in silo height-to-diameter ratio results in a more pronounced non-uniformity in the internal stress distribution of the storage material,the static lateral pressure of the storage material is in good agreement with the Chinese code.The relative dynamic lateral pressure of the shallow silo model varies more uniformly along the silo height,while the deep silo model has a large amplification effect on the relative dynamic lateral pressure close to the top under the large seismic condition.