Study Of Wind-induced Vibration Response And Wind-induced Vibration Factor For Long-Span Gable Roofs Supported By Steel Truss

Due to its original and unique shape,long-span roof structure is widely applied into public constructions,such as gymnasium,exhibition center,theater and industrial building,which can get larger service space.Generally,such structure has lager flexibility,low damping and natural frequency.When wind flows around roofs,the airflow will be separated to form a high suction zone,so that the roofs will suffer from wind-induced vibration response,thus wind load is critical or control load in structural design.In current Chinese code of wind load on buildings and structures,random vibration theory is used to calculate about wind-induced vibration of long-span gable roofs when natural period is more than 0.25 seconds,but no formula is presented.Based on random vibration theory,a wind power spectral analysis method in the frequency domain is used to analyze wind-induced vibration response of long-span gable roofs supported by steel truss in ANSYS in this paper.The influence of parameters such as high order mode shapes,basic wind pressure,span and weight of the roof,damping ratio,terrain categories and support restraints,which are usually critical to the wind-induced vibration responses,are discussed.Furthermore,the influence of parameters such as the basic wind pressure,span and weight of the roof, damping ratio,terrain categories and support restraints,which are usually critical to the wind vibration factor,are also discussed.According to results of the parametric analysis,a practical wind-induced vibration factor formula for long-span gable roofs supported by steel truss is summarized,which can be applied in practical engineering design and research.The influence of power spectrum density to the wind-induced vibration responses and wind vibration factor is discussed,at last.