Study Of Stability Of The Prefabricated Ground-supported Corrugated Steel Silo Under Loading Of Grain

The prefabricated steel silo has been widely used in industry and agriculture due to its low steel consumption,high degree of industrialization and simple construction.The profiled steel sheets with vertical stiffener are usually used for prefabricated steel silo wall.However,the profiled steel sheet is orthotropic,thereafter it is assumed that the prefabricated steel silo is a ribbed anisotropic shell,of which stability is the key and difficult point for structural design.Because of late beginning and short of experience on the prefabricated groundsupported corrugated steel silo,the calculation formula for the stability of this type of structure in Chinese "Code for Design of Grain Steel Silos"(GB 50322-2011)is rough,and cannot truly reflect the buckling load carrying capacity.In order to investigate the actual stress state of the prefabricated steel silo and its stability mechanism,this thesis used ABAQUS to shed light on the method for numerical analysis and failure mechanism of stability of the prefabricated steel silo.The main work of this thesis is as follows:(1)Based on the equivalent constitutive equation of corrugated sheets given by Eurocode 3,a finite element model of corrugated steel sheets containing orthotropic shell elements was established.The nonlinear finite element analysis of the shear performance was carried out with the in-plane shear test data of corrugated steel sheets compared.The results show that the finite element model including orthotropic shell elements proposed in this paper has less number of elements and thus calculated faster,whilst it can accurately reflect the shear stiffness of corrugated steel sheets for the simulated shear deformation is in good agreement with the experimental results.(2)Considering design of strength and stability for a small prefabricated corrugated steel silo in the “Code for Design of Grain Steel Silos” in China,an in-depth interpretation of the relevant provisions on the stable design of the silo was proposed and comparative data for subsequent research was provided.(3)Combining the orthogonal anisotropic shell element finite element model in(1)to build a fabricated steel silo model,and different element types were tried in order to take the buckling analysis of material nonlinearity and geometric nonlinearity into consideration.The results show that after the prefabricated corrugated steel silo was checked and verified by the silo wall stability check formula given by the specification,the silo wall instability damage may still occur,which thus cannot accurately reflect the stability performance of the silo wall.In this regard,when structural engineers design the prefabricated corrugated steel silo,using the numerical simulation method for stability check is advised.The numerical simulation method used in this paper can be used as a reference.