| Base on the investigation of the low-rise building destruction in typhoon region, the wind tunnel experiment and numerical simulation are carried out to research the wind loading characteristic of low-rise cold-fromed steel residential house. The main innovative arguments and results of this dissertation are following:1. Wind tunnel experiment of low-rise cold-fromed steel residential house models, which considering the roof form and house shape are carried out is the first innovative argument in this dissertation. The models are divided into 4 forms:"一" shape house with gable roof, "一" shape house with hip roof, "L" shape and "T" shape house with gable roof. Some parameters, such as roof form, roof pitch, wind direction, the length of roof overhang are considered in the test. The test method and procedure are introduced detailly in the paper, the isonline of pressure coefficient on roof of each model in every working condition are shown, and the shape coefficients of building are proposed in the paper. Finally, they are compared with each other.2. Based on various Reynolds Averaged Navier-Stokes Equations (RANS) turbulence models, i.e. standardκ-εmodel etc. provided by professional computational fluid dynamics software Fluent 6.3, the 3D steady wind flow field around standard low building TTU and standard high building CAARC in atmospheric boundary layer are numerically simulated, and the simulating results are compared with the data obtained from the wind tunnel experiment. The method of how to found the reasonable numerical wind tunnel is researched. These parameters including how to divide the gird, how to choose the turbulence model and the how to setup the key parameters in the numerical simulation.3. The RNGκ-εturbulence model is used to simulate the 3D wind flow field around the models which are tested in the wind tunnel. Then, the influence parameters on pressure coefficient and shape coefficient of building are researched systematicly. These parameters are wind direction, roof pitch, length of overhang and length-width ratio of building. These researches are the second innovative argument. Numerical simulation results show that Positive mean wind pressures appear on the windward surface, and there is little influence of building dimension on shape coefficient. The pressure on the leeward surface is negative. The wind direction, roof pitch and eaves hight will influence the distribution and magtitude of wind pressure on roof obviously. But, the length of overhang has no influence. 4. Wind tunnel experiment and numerical simulation, which considering the interactions between the same shape of gable roof and hip roof houses, are carried out. The mean and fluctuating wind pressure coefficient under the different space between two houses and wind direction are put forward in the dissertation, and the shape coefficient and interference factor are given out too. These researches are the third innovative argument. When disturbed house is in disturbing house wakes, the occlusion effect is obviously. When two houses are arrangement in parallel, the slit effect is obviously and the wind speed is increased.5. Wind tunnel experiment and numerical simulation, which considering the opening on the wall, are carried out. The relationship between inner pressure coefficient and outer pressure coefficient is founded. The influence rule of opening position and dimension on pressure inside and outside are put forward. And then, the house with openings both on windward and leeward wall is researched. These results are the forth innovative argument in this dissertation. Research results show that the opening position and dimension have no influence on the pressure coefficient of the outer surface and wind flow field outside, when the opening is on the windward surface. When the opening is on the wall of side wind, the inner pressure coefficient is determined by the flow characteristic of the position, where opening is. When the openings are on the windward and leeward walls, the velocity of flow in the inside of house is very small; there is no influence to the outer flow field. And the inner pressure coefficient can be calculated by the theory formula.6. The design method and suggestions on wind loading of low-rise cold-formed steel residential house are put forward, and the simplified method to calculate the shape coefficient of house is suggested in this dissertation. These results are the fifth innovative argument.
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