Study On Seismic Performance Of Coupled Steel Silo Composite Shear Wall

Steel silo composite shear walls have been gradually applied in practical engineering as an efficient lateral resistance component.To satisfy the functional demands of buildings,a coupled steel silo composite shear wall is comprised of two or more shear wall piers connected with steel coupling beams on each floor.The seismic design strategy is that steel coupling beams yield in advance and dissipate energy to reduce the damage to composite wall piers for the purpose of optimizing the seismic performance of the structure.However,the current research on the steel silo composite shear wall has primarily concentrated on the components,with limited attention given to the coupling system and failure mechanism.Therefore,this paper carries out research on the seismic performance of a novel coupled steel silo composite shear wall through numerical analysis.The main research contents and conclusions are as follows:(1)The cross sections of steel coupling beams were varied to regulate coupling ratios while maintaining the parameters of the combined wall piers constant.To investigate the effects of different coupling ratios on the seismic performance and failure characteristics of the coupled steel silo composite shear wall,a total of 10 finite element analysis models were established.The models were subjected to monotonic pushover and cyclic reciprocal loading.According to the findings,there is a gradual increase in the likelihood of combined wall piers yielding before steel coupling beams as the plastic coupling ratio(CR_p)increases.With a low coupling ratio(CR_p<45%),the webs of steel coupling beams suffered plastic damage and cracked,ultimately leading to the failure of the coupling system.With a high coupling ratio(CR_p>60%),combined wall piers failed prematurely with insufficient energy dissipation in steel coupling beams.With a medium coupling ratio(45%<CR_p<60%),the comprehensive seismic performance of coupled steel silo composite shear walls is better.Based on a thorough evaluation of seismic performance indicators and failure characteristics,it is recommended that the plastic coupling ratio be restricted to a range of 45%to 50%.Additionally,the ratio of plastic coupling ratio to elastic coupling ratio(CR_p/CR_e)should not exceed 90%to ensure that steel coupling beams yield prior to combined wall piers.(2)On the basis of the established optimal coupling ratio range,the coupled steel silo composite wall with a plastic coupling ratio of 48.5%was chosen for subsequent parametric analysis.The study aimed to investigate the impact of axial compression ratio,steel tube arrangement,and wall piers reinforcement on the seismic performance of the selected composite wall.The findings indicate that the seismic behavior of the specimen deteriorated as the axial compression ratio increased.In particular,the deformation and energy dissipation capacities of each combined wall pier were constrained under the combined effects of alternating top pressure and additional axial force.Consequently,the combined wall piers exhibited progressive failure prior to the steel coupling beams.The seismic performance of coupled steel silo composite shear walls is notably affected by the spacing of steel tubes at the lowermost level.Nevertheless,an excessively narrow spacing of steel tubes may lead to the over-strengthening of the combined wall piers and severe damage to steel coupling beams,ultimately compromising the structural ductility.It is advisable to adopt a steel tube spacing of 400～500 mm(with a spacing-to-steel plate thickness ratio of 80～100)for optimal structural performance.Additionally,the bottom spacing should be reduced while the upper spacing should be increased as necessary.To minimize stress concentration,the spacing of steel tubes should be adjusted at transition arrangements.The lateral bearing capacity of the specimen can be enhanced by welding steel plates or adding bolts to reinforce the combined wall piers,and the seismic performance of the specimen can be improved without a notable reduction in the coupling ratio.