Design Of Shock Absorption And Isolation For Parking Buildings Considering Random Parking

With the rapid development of the Chinese economy,the ownership of private cars has increased linearly,and the difficulty of parking has become increasingly prominent.Due to land and space constraints,many cities have begun to build parking garages to ease parking pressure.In the design of parking buildings,vehicle loads are usually arranged in the form of live loads.However,in the actual work of parking buildings,random parking of vehicles,especially uneven and asymmetric parking,causes the parking structure to twist under the action of a large earthquake.The possibility of damage is significantly increased,and there are considerable uncertainties in the elasto-plastic verification of structures with three or seven waves in the traditional seismic design(which is greatly affected by the selection of seismic waves).Therefore,the traditional seismic design of parking buildings is The high-intensity fortification area is at risk of collapse.This article takes a three-dimensional parking building in Dali,Yunnan Province as an example(8 degrees 0.2g).This steel structure parking building considers the dynamic response,reliability,and collapse probability of the parking building structure under random parking and random earthquake excitation.The results of the analysis are based on seismic isolation design,and the probability density evolution theory is used to evaluate whether the structure of the parking building can meet the third-level design requirement "large earthquake does not fall" after large earthquakes after seismic isolation design.The structural design,reinforcement and post-earthquake loss assessment provide reference.The main research work and conclusions of this paper are as follows:(1)The finite element software ABAQUS is used to model the structure of a three-dimensional parking building considering random parking of vehicles,and a MATLAB program is compiled to call the ABAQUS calculation model to analyze the dynamic response of the model under random seismic excitation(interlayer displacement angle,interlayer torsion angle,layer Inter-displacement velocity,inter-layer torsional angular velocity).The MATLAB program is used to call PYTHON to read and analyze the ODB data.Finally,the probability density evolution program is used to complete the reliability calculation.The analysis results show that when considering random parking of vehicles and random earthquake excitation,the maximum inter-story displacement angle of the parking structure decreases,the maximum inter-story torsion angle increases,and the instantaneous probability density curve of the inter-story torsion angle of each layer of the structure changes significantly."Fat",the torsional response of the parking building structure when subjected to a large earthquake significantly increases,and the instantaneous probability density curve of the displacement angle between floors is almost unchanged,indicating that the displacement angle between floors is hardly affected by the random parking of vehicles.The reliability value calculated by using the inter-story displacement angle as the reliability index during the rare earthquake is not affected by the random parking of the vehicle and will not collapse.When considering the random parking of the vehicle and using the torsion angle as the index,the structure has 9.18% probability of collapse.Therefore,in the design of the parking building,the influence of random parking of vehicles must be considered,both the displacement angle index between floors and the twist angle index between floors must be met.(2)Still using the parking building as the research background,the traditional shock absorption design of the parking building is to meet the index of the displacement angle between floors,and the probability density evolution theory is used to perform a large earthquake under the shock-absorbing parking building model considering random parking of vehicles.Calculation of the reliability and collapse probability,it is concluded that the arrangement of the damper can improve the structural reliability of the structure under the action of a large earthquake and reduce the probability of collapse of the structure,but even if the interlayer displacement angle reaches the shock absorption through the arrangement of the damper The goal is to take into account that the parking structure of vehicles parked randomly still has a 2.47% probability of collapse,so the traditional parking building shock absorption design actually overestimates the seismic performance of the structure.(3)Of the parking building by reducing isolation combination technology isolation design,through the probability density evolution theory considering random vehicles parked isolation model reliability under strong earthquakes and collapse probability calculation,draw the conclusion: by isolation combination technology effectively reduces the parking building structures during strong earthquakes of translational and torsional,even if they don’t consider random parked vehicle,reduce isolation combination parking building structure still meet the requirement of the third level in China seismic design code is "big to fail".Therefore,in the combined design of anti-isolation parking structures,even if the random parking of vehicles is ignored,the structure of anti-isolation parking structures will not collapse.However,considering the random parking of vehicles is helpful to provide more accurate post-earthquake damage status assessment for projects of three-dimensional parking structures with similar steel structures.