Research On Multi-objective Equivalent Static Wind Load Of Long-span Roof Structures

With the development of society and the continuous improvement of the requirements for building performance,large-span roof structures have been widely used due to their large structural clearance,reasonable structural forces,and beautiful shapes.At the same time,most of the large-span roof structures are light in weight,low in rigidity,and sensitive to wind loads.Therefore,the wind resistance of largespan roof structures is becoming more and more important.However,the wind resistance theory of large-span roof structures is not yet mature,and the code does not provide a calculation method for wind resistance of large-span roof structures.Based on the study of wind load on the surface of the long-span roof structure and the analysis of the structural wind-induced response,this paper conducts a study on the equivalent static wind load of the long-span roof structure,and takes a conference center as an example for calculation.The wind load time history on the surface of the structure is obtained through wind tunnel tests.the wind load time history is subjected to proper-orthogonal decomposition(POD).the eigenmodes of the wind load are analyzed.and the wind load is reconstructed from the eigenmodes of the wind load.How to choose the eigenmode for reconstruction of wind load was studied.The influence of wind load sampling time and number of sampling points on the eigenmode of wind load is analyzed.The difference between the interpolation results of the three interpolation methods,inverse distance weighted interpolation,Kriging interpolation,biharmonic and spline interpolation,in time-domain interpolation and eigenmode interpolation is compared.The structural characteristics of the large-span roof structure are studied.The difference of wind load based on the wind pressure interpolation method among the above three interpolation methods with the smallest error and the nearest neighbor interpolation method is compared.The difference in wind-induced response when it acts on the structure reflects the importance of obtaining accurate wind loads on the surface of the structure.The wind-induced response of the structure is decomposed into average response,background response,and resonance response,and the proportion of each component in the structure response is discussed.The results show that the mean square error of the resonance response accounts for the main part of the mean square error of the wind-induced response.The relationship among the structural response under the four equivalent static wind load base vectors of average wind load,wind load mean square error,load response correlation coefficient load and wind load eigenmodes,and the average wind response of the structure and the mean square deviation of wind response are studied.The equivalent accuracy of the equivalent static wind load is compared when the average wind load is combined with the four basic vectors.The difference between the displacement equivalent target and the reaction force equivalent target is compared.