Study On Wind Load Characteristics And Wind-resistant Design Methods Of Irregular Shape Long-span Roofs

With the development of economy and progress of science and technology, more and more long-span roofs have been built, which have individual characteristics in architecture and structure. Since long-span roofs are generally light, flexible and low damping, they are prone to wind and the wind load is one of their most important loads to control the structural design. Due to the complexity of long-span roofs in wind loads and structural styles, there is no effective method to research the wind-induced dynamic responses. In order to provide a systematic research about the wind-resistant analysis and design of long-span roofs, investigations on analysis of wind pressure distribution characteristics, wind load on cladding structures, static wind response and stability, wind-induced vibration characteristics, wind-resistant design methods, are processed on this thesis.The research is mainly focused on the following aspects:1. Research on the characteristics of wind load distribution on long-span roofs.Based on the wind tunnel model test of Peking 2008 Olympic Game ping pong gymnasium and Quanzhou channel sport center gymnasium, the characteristics of mean wind pressure and fluctuating wind pressure on long-span roofs are studied in details and some common laws about wind pressure distribution are obtained. Under the condition of with and without surrounding buildings, the interference effects of surrounding buildings are discussed.2. Analysis on static wind response and ultimate carrying capacity of long-span roofs.Based on the test results, static wind response analysis is done and the methods to choose the worst wind direction are discussed. Taking the geometry nonlinearly, the material nonlinearly and supporting condition nonlinearity into account, the static wind ultimate carrying capacity analysis of long-span roofs is processed. Meanwhile the effect of initial pre-stress and supporting condition are considered.3. Research on the characteristics of wind-induced vibration on long-span roofs.Based on the aforementioned research, the form reasons of fluctuating wind pressure are discussed. After a series of conversion and amendment, the nodes' fluctuating wind load history-time can be gotten from the measured points' wind pressure coefficient history-time, which can be used for the wind-induced vibration response analysis. The wind-induced vibration forms and mechanisms are studied and the wind-induced vibration coefficients are calculated. Meanwhile the effect of initial pre-stress and supporting condition are considered.4. Research on the wind-resistant design methods of long-span roofs.On the fundament of field investigations of the long-span roofs' damage, the main factors which affect the wind-resistance capability of long-span roofs are analyzed and the basic wind pressures...