Research on Wind Vibration Effect and Equivalent Wind Load of a Desulphurization Tower with Variable Cross-sections
Variable cross-section is a common type of structure in engineering design.Wind effect of this structure has received less attention in the current codes,and the regulation is still rough.In this paper,a high-rise desulfurization tower is taken as an object.With integrating the time domain and frequency domain numerical simulations,the wind-induced dynamic response characteristics of its cylindrical high-rise structure with multistage variable cross-sections in along-wind and across-wind directions are studied in detail.The judgement and calculation methods of vortex-induced resonance are discussed.The difference and reliability of the common calculation methods of equivalent static wind load applied to such a structure are analyzed.The results show that the first mode of the structure is the dominant mode of the wind effect of this kind of desulfurization tower,and the contribution of the upper vortex-induced vibration of this kind of structure to the across-wind response should be paid more attention.Since the wind-induced vibration of the desulphurization tower is mainly resonance response,equivalent wind load calculated by methods of Inertia Wind Load or three components(mean,background and resonant)is more consistent with the actual distribution law.In addition,the results of the time domain and frequency domain analyses agree well with the results of Chinese current code(GB 50009-2012).This work may provide an engineering reference and basis for the study of fine wind vibration effect of high-rise structures with multistage variable cross-sections.