Analysis Of Wind Resistance And Seismic Performance Of Large-span Natatorium

Large stadiums,exhibition centers,natatorium and other public buildings are widely used in actual projects by virtue of their unique shapes and functions.These large-span space structures are usually steel roof structures on top and concrete frame structures on the bottom.The complex shape and its own characteristics make the large-span space structure more and more sensitive to wind and seismic effects,and even wind load and seismic effects play a major controlling role.In the face of such a complex structural form,it is necessary to study its wind and seismic performance.In this paper,a large-span hybrid structure natatorium in Xi’an is taken as the research object,and the wind and seismic performance analysis is carried out using the finite element numerical simulation method to provide a reference basis for the analysis of this kind of large-span space structure.The main research contents and conclusions of this paper are as follows:(1)Using Midas-gen and 3D3 S finite element software,the finite element models of the steel roof structure and the hybrid structure in Area A of this large-span natatorium were established respectively,and the dynamic characteristics were compared and analyzed,and the maximum error of the self-oscillation period obtained by the two software calculations was6.73%,which verified the correctness of the finite element model of this natatorium.(2)The geometric model of the standard 6m×6m×6m cube was established,and the same turbulence model and boundary conditions and other parameters as the wind tunnel test of the cube were selected,and the wind load was simulated numerically by using ANSYS finite element software.By comparing the numerical simulation measurement point data,the field measured data and the average wind pressure coefficients of 15 wind tunnel tests,it was found that the average wind pressure coefficients obtained by the three methods were in good agreement,which verified the reasonableness and reliability of the numerical simulation method.(3)Numerical simulations were used to obtain the average wind pressure coefficients on the roof surface of the natatorium A model and the overall model,to obtain the A zone body coefficients under 135° wind direction angle,and to analyze its static performance under wind loads.The results show that: the simulation results of this swimming pool match well under different turbulence models and can effectively predict the wind pressure distribution on the surface of the natatorium;the wind direction angle has a large influence on the average wind pressure coefficient on the surface of the natatorium roof;there are low buildings in front of the building,which will form a gentle slope structure to resist part of the incoming flow,resulting in a relatively flat gradient of the average wind pressure coefficient change.(4)Modal analysis and response spectrum analysis of steel roof structure and hybrid structure in Zone A were carried out by Midas-gen finite element software to study the structural displacement and internal force response under vertical seismic action,XZ seismic action and YZ seismic action.The results show that: the overall combined displacement of the hybrid structure increases significantly after considering the lower concrete frame structure;the horizontal seismic action has a greater effect on the displacement in the corresponding direction;the maximum values of the axial forces of the key bars increase by 81.2% and 49.2% under the XZ seismic action and YZ seismic action of the hybrid structure compared with the vertical seismic action;the internal forces of the lower chord bars change significantly than those of the upper chord bars.(5)Selecting three suitable seismic waves,the dynamic time analysis of the hybrid structure of natatorium A shows that under the action of YZ earthquake,the axial force of the lower chord member increases by 23.2% compared with that of the upper chord member;the calculation result of the time analysis method is small;under the combination of wind load and earthquake action,the maximum stress increases by 42.3%,which has a significant effect on the internal force of the hybrid structure.