The Wind-induced Vibration Analysis Of The Long-span Single Layer Space Groined Latticed Vaults

Due to their outstanding advantages, the space groined latticed vaults ,as a specific type of long-span reticulated shell structures are widely used in constructions including theaters, exhibition halls, hangars, airports, stadiums, stations, coal sheds, storehouses and industrial premises, and become larger and more diversified and complicated than before. Wind load, which is applied on such structures, is random and space-correlated, and is always the major or even the most important one. Wind effects become one of the dominating factors that must be considered during the wind-resistance design and disaster prevention analysis. So far, progress in wind engineering research of long-span reticulated shell structures are only staged, and the research is not sufficient. Key problems such as wind-induced response and wind-induced vibration coefficient are not completely solved; even the research on structural dynamic characteristics is not enough. Dynamic response research of reticulated shell structures under wind load is paid more and more attention by both engineers and academe.This paper focuses on the following aspects: grid generation techniques of space groined latticed vaults, wind load form coefficient and wind pressure distribution of the structures, simulation of wind speed and wind load,and time domain analysis of wind-induced vibration and parametric analysis.At first, general situation of research on wind engineering of long-span reticulated shell structures is reviewed, the existing major questions are stated, and the research work and target is presented.Then, calculating models for single-layer space groined latticed vaults, are established with parametric modeling method, which is on the basis of Formex Algebra method. By inputting several controlling parameters, data files containing information of node, element and boundary condition are formed. In this way, data input work load is reduced, and the method is applicable to the finite element pre-processing of the same type structures.Numerical wind tunnel test is one of the advanced and integrated technology consolidated with computing fluent dynamics, finite element method, wind engineering, structure engineering and computer languae, high efficient numerical algorithm, computer graphic and dynamic visulization. The technology are used in the paper to study the form coefficient and wind pressure distribution of space groined latticed vaults, to analyzes the reason of the result of computing wind engineering. The reliability of the numerical wind tunnel test is testified and some conclusions of the form coefficient of sub-area of structure are gotton.As to the simulation of time domain analysis of wind velocity and wind load time series, the harmony superposition method is employed to simulate wind velocity time series of space groined latticed vaults with the properties of randomness, time-correlation and space-correlation. The statistic analyzation of the result of time domain analysis of wind speed and the power spectrum analyzation are derived and the target value and the simulation value are tesified to match with each other closely. Furthermore, based on the characstics of the wind velocity time series, wind speed time series has been changed to win load time series.Then, following the review of basic research situation of structural wind-induced vibration, different types of structural wind induced vibration and their mechanisms are analyzed, characteristics of wind load applied on the reticulated shell structures are discussed, and the computational methods for structural wind-induced vibration are investigated. In this paper, several concepts such as Wind-induced Vibration Coefficient of Nodal Displacement and Wind-induced Vibration Coefficient of wind load are introduced, and Newmark method is employed to investigate the wind-induced dynamic response analysis of the space groined latticed vaults. The coefficient of wind-induced vibetation of the space groined latticed vaults is caculated, and concluded to the coefficient of wind-induced viberation of the blocks used by design.Finally, based on the research work of the whole paper, some conclusions are drawn and some questions to be further studied are indicated.