Seismic Analysis Of Anti-buckling Energy Support In Irregular Structures

With the rapid economic development and social progress,complexity and functionality have become the trend in modern architectures.Irregular building structures are becoming more and more,and they have become the mainstream trend of future buildings.However,due to its complex shape and irregular structure,these characteristics are extremely unfavorable to earthquake resistance.Therefore,the structure is more likely to produce stress concentration or weak layer when the earthquake occurs,and the earthquake mainly causes torsional damage to the structure.So researches on seismic performance of irregular structures are very important.Combining with previous researches,this article is based on the engineering example,it select a key fortification class planar L structure as the research object,and add anti-buckling energy support in pure frame structure,carries on the finite element analysis and structure calculation,and study the rule arrangement of the anti-buckling energy support in the planar L irregular structure.The main research work of this paper is as follows:(1)In this paper,the anti-buckling energy support and irregular structure are studied theoretically,the working mechanism and simplified mechanical model of the anti-buckling energy support are introduced,and the parameters of the simulation element in the finite element software are given.(2)Based on the principle of stiffness equivalence,the Bouc-Wen model is used to simulate the buckling-resistant bracing of the annexed podium structure of Baowen International Square in Binhu,Hefei.Several calculation models are obtained by different arrangement of buckling-resistant bracing.Then,the rationality of the periodic reduction coefficient of the frame structure in the current code is discussed through modal analysis.(3)The paper uses SAP2000 finite element analysis software,the whole anti-buckling energy support structure is analyzed by mode decomposition response spectrum analysis.Through the results,we can find that comparing with the pure frame structure,the anti-buckling energy support structure has more uniformly vertical distribution on the lateral stiffness,the displacement angle between elastic layers and other parameters meet the current specification.According to different arrangements,the base shear force also changes correspondingly,which further illustrates the superior effect of anti-buckling energy support on the overall seismic performance of the structure.(4)We select two natural waves and one artificial wave to carry out the elastoplastic time-history analysis.The results show that,in the case of frequent earthquakes,the addition of anti-buckling support can effectively reduce the displacement response of the whole structure,reduce the displacement Angle between layers,and make the whole structure conform to the standard requirements.In rare earthquakes,anti-buckling energy-consuming support can significantly reduce the displacement response of the overall structure,reduce the adverse impact of seismic waves on the overall structure,and protect the main structure effectively from collapse or serious damage.The results show that the period ratio,displacement ratio,layer displacement,inter-layer displacement Angle and other parameters of the structure are significantly reduced after the anti-buckling energy support is added in rare earthquakes.The hysteretic curves are relatively full and the energy-dissipation effect is obvious.(5)Pushover analysis was carried out for pure frame model and several models with anti-buckling energy support.According to the distribution and development degree of plastic hinge of beam and column,the addition of anti-buckling energy support effectively restrains the development of plastic hinge.No matter in the elastic stage or plastic stage,the anti-buckling energy support can improve the stiffness of frame structure and better meet the seismic requirements.When anti-buckling energy support is arranged vertically,plastic hinge can be ensured in a small number of frame beams and columns at the bottom of the structure in the performance point state,but plastic hinge is basically in a safe state,indicating that anti-buckling energy support can protect the main structure from damaging.