低矮房屋结构风效应极值的不确定性、相关性、方向性与设计风荷载

The provisions of design wind loads on low-rise buildings specified in the code of our country and corresponding wind-resisting design are desperately inadequate. The systematic study of wind loads and responses for low-rise buildings is desiderated to perform, which can lay the solid theoretical foundation for the development and improvement of the wind load code-specified provisions in our country. In this project, the theoretical research on the random uncertainty of extreme wind effects will be carried out. By considering the uncertainty and correlation of extreme wind effects, the probability distribution model of extreme wind load effects can be built; On this basis, the partial factor of wind load will be examined and endowed with clear physical meaning. Regarding the correlation of extreme wind responses and extreme wind loads for main load-resisting frames of low buildings, the theoretical study is planned to conduct and furthermore the joint probability distribution model of extreme wind load effects can be established; The combination factor of wind load acting on main load-resisting frames will be obtained based on the base vector of extreme wind load. Consequently, the determination method of design wind load for main load-resisting frames should be presented. The directionality corresponding to extreme wind effects of cladding/components and main load-resisting frames of low-rise buildings will be studied theoretically. Furthermore, based on the uncertainty, correlation and directionality of extreme wind effects, the probability distribution model of extreme wind effects can be proposed. Additionally, the method to determine the reduction factor of wind directionality for cladding/components and main load-resisting frames of the low-rise building will be presented.

我国低矮房屋设计风荷载的规范规定及抗风设计尚存在严重不足，亟需对低矮房屋风荷载、风响应开展系统的研究工作，为发展和完善我国规范风荷载规定奠定坚实的理论基础。本项目将对风效应极值的随机不确定性开展理论研究，建立风荷载效应极值的概率分布模型；在此基础上，校核风荷载分项系数，并赋予其明确的物理含义。对低矮房屋主体结构风响应极值、风荷载极值的相关性开展理论研究，建立风效应极值的联合概率分布模型；以风荷载极值为基向量，确定主体结构风荷载分量的组合系数，提出主体结构设计风荷载的确定方法。对低矮房屋围护结构、主体结构风效应极值的方向性开展理论研究，考虑风效应极值的不确定性、相关性和方向性，建立风效应极值的概率分布模型，提出低矮房屋围护结构、主体结构的风荷载风向折减系数的确定方法。

我国低矮房屋设计风荷载的规范规定及抗风设计尚存在严重不足，需对低矮房屋风荷载、风响应开展系统的研究工作，为发展和完善我国规范风荷载规定奠定坚实的理论基础。本项目对风效应极值的随机不确定性开展了理论研究，建立了风荷载效应极值的概率分布模型。对低矮房屋主体结构风响应极值、风荷载极值的相关性开展理论研究，建立了风效应极值的联合概率分布模型；以风荷载极值为基向量，确定了主体结构风荷载分量的组合系数，提出了主体结构设计风荷载的确定方法。对低矮房屋围护结构、主体结构风效应极值的方向性开展理论研究，考虑风效应极值的不确定性、相关性和方向性，建立了风效应极值的概率分布模型，提出了低矮房屋围护结构、主体结构的风荷载风向折减系数的确定方法。