Seismic Performance Analysis Of Irregular Structures With Viscous Dampers Based On Site Characteristics

Due to the unique shape of the irregular structure,the center of mass is far apart,and it is prone to torsion under the action of the earthquake and the damage of the structure is aggravated.At the same time,different site types and earthquake groupings will lead to different degrees of damage to the structure under the action of earthquakes.In order to reduce the damage degree of the structure under the earthquake,the viscous damper is reasonably arranged in the irregular structure,which can consume the energy generated by the earthquake and reduce the damage of the structure.Therefore,it has important theoretical significance and application value to study the variation law of seismic response of controlled and uncontrolled irregular structures caused by different site characteristics.In this paper,21 models are established to study the seismic performance of uncontrolled and controlled irregular frame-shear structures considering site characteristics.The main research contents and results are as follows:(1)This paper takes an irregular performing arts center as the research object,and designs two shock absorption schemes under the premise of giving full play to the shock absorption performance of viscous dampers.The seismic responses under large earthquakes are significantly reduced,and the shock absorption effect of the second scheme is better than that of the first scheme;in addition,the study found that the two schemes are better than the other in reducing the severe damage and moderate damage of the irregular structure under the large earthquake.In terms of damage level,it has a better effect.(2)For the original uncontrolled irregular structure,change the site category and earthquake grouping respectively and conduct small earthquake response spectrum analysis.The analysis data shows that the seismic response of the structure increases by 10%,18%and 9%from site categories Ⅰ0 to Ⅲ,but the seismic response of the structures from site categoriesⅢ to Ⅳ basically does not change;The seismic response increases by about 4%,but the seismic responses of the structures in the second and third groups of earthquakes do not change.Therefore,it can be seen that the sensitivity of the uncontrolled irregular structures to the site category is significantly higher than that of the earthquake groupings.(3)Change the site category and earthquake grouping for the original uncontrolled structure,and conduct dynamic time history analysis under rare earthquakes.The calculation results show that the seismic response of the structure increases by 17%,15%,and 19%intum from site categories Ⅰ0 to Ⅲ under a major earthquake,and the seismic response of the structures from site categories Ⅲ to Ⅳ basically does not change..From earthquake grouping 1 to 3,with the change of earthquake grouping,the seismic response of the structure basically does not change.(4)Change the site category and earthquake grouping for the controlled structure using the two shock absorption schemes,and perform calculation and analysis under s mall earthquakes.The calculated data show that the seismic response of the structure increases by 10%and 17%respectively from site categories Ⅰ0 toⅡ,but the seismic response of the controlled structures from site categories Ⅱ to Ⅳ changes very little.From earthquake grouping 1 to 3,the seismic response of the controlled structure is basically unchanged for each level of earthquake grouping.(5)For the controlled structure adopting the shock absorption scheme 1 and scheme 2,change the site category and earthquake grouping respectively,and carry out the dynamic elastic-plastic time history analysis under the rare earthquake.The analysis shows that the seismic response increases by 16%,15%and 14%in turn from site categories Ⅰ0 to Ⅲ,but the seismic response of controlled structures from site categoriesⅢ to Ⅳ changes very little.The seismic responses of the controlled structures from earthquake groups 1 to 3 are basically unchanged.(6)Comprehensively compare the shock absorption effect of each controlled model relative to the uncontrolled model under different site conditions.The comparative study shows that the shock absorption effect of the viscous damper in the class Ⅲ site is significantly better than that of other site conditions.