Research On Wind Pressure Characteristics And Wind-induced Dynamic Response Of Structure Of Ultra-long And Ultra-wide Steel Structure Factory

Due to the large windward area,the out-of-plane rigidity is weak,the fundamental frequency is low of the ultra-long and ultra-wide large-scale industrial factory building and it is easy to resonate with the low-frequency part of the random wind load.A strong wind suction effect on the roof,back and side envelope structures will be caused by the huge windward surface.At the same time,irregular roof structure and obvious turbulent phenomenon result in complex roof wind pressure distribution characteristics.These factors will cause structural wind-induced damage,so it is of great significance to study the wind pressure distribution characteristics and structural windinduced dynamic response of super-long and super-wide large industrial factory.In this paper,the wind pressure characteristics of ultra-long and ultra-wide steel structure factory roof structure under wind load are discussed.In the meanwhile,the complex wind-induced dynamic response of structure is analyzed to study the failure characteristics and failure mechanism of enclosure structure.The main research work and results are as follows.1 Analysis of roof wind pressure characteristics of ultra-long and ultra-wide steel structure factory is carried out based on numerical wind tunnel.Qualitative and quantitative analysis of average wind pressure coefficient distribution characteristics of roof enclosure structure of factory which is implemented by series of relevant finite element simulation.Comparing the simulation results with the current specification,the applicability of the specification is discussed.The wind pressure characteristics of roof under different influence factors are summarized based on wind direction angle effect,different landform types and size effect.In the meantime,combined with the complex change process of wind field caused by wind load and fluid-solid coupling between structures,the correlation between structural flow field change and wind pressure distribution characteristics is discussed to summarize the mechanical characteristics and failure mechanism of the ultra-long and ultra-wide roof enclosure structure under wind load.2.Numerical wind tunnel models considering the wind pressure distribution characteristics of indoor and outdoor roof structures under different skylight opening rates are established.Based on the control of the opening rate of the pneumatic skylight,the discrete points of the wind pressure coefficient of the indoor and outdoor roof structures with different roof opening degrees are obtained and the numerical fitting is conducted.Through the qualitative and quantitative research on the distribution of roof wind pressure coefficient,the variation law of discrete degree caused by the opening degree to the discrete points are obtained.In one time,it is concluded that the stress state of indoor and outdoor roof and the change mechanism of wind pressure distribution characteristics affected by the opening degree of skylight under steady state.3.Wind-induced dynamic response analysis of structure of ultra-long and ultra-wide steel structure factory in time domain.Based on the harmonic superposition method,the artificial wind speed time history of main nodes with different target spectrums considering horizontal fluctuating wind and vertical fluctuating wind is obtained by MATLAB,and the wind load time history generation is completed to apply to each node for time history analysis.Time history curves of displacement and acceleration of characteristic nodes of enclosure structure are obtained.The response spectrum nodal displacement and acceleration obtained by Fourier transform are analyzed.Meanwhile,the influence of typical wind direction angle on structural displacement wind vibration coefficient under wind-induced dynamic response is discussed..