Vulnerability Analysis Of Prefabricated Frame Structure In Villages And Towns Under Wind Load

In recent years,prefabricated structure has been widely used in Chinese cities because of its advantages of energy saving and industrialization,however,most of the houses in villages and towns are still built by villagers themselves,due to the lack of reasonable planning and design,the wind resistance measures of these houses are simple and the wind resistance ability is difficult to guarantee,based on the advantages of prefabricated structures and relevant national policies,it is the future development trend to promote the application of prefabricated buildings in rural areas as soon as possible,so it is required to analyze the wind resistance performance of this type of structure.At present,the research on prefabricated structure mostly focuses on its seismic performance and joint connection form,so it is necessary to study the wind resistance performance of the structure both theoretically and practically.Therefore,the paper takes the prefabricated frame structure in villages and towns as the research object,analyzes its vulnerability to wind disaster based on performance,and evaluates its wind resistance ability by comparing with the cast-in-place structure of the same size.The main research contents in the article are as follows:（1）Firstly,the establishment method of the node model of the fabricated structure is given,then a three story fabricated frame structure and a cast-in-place structure with the same size for comparative analysis are designed according to the specification,and the finite element models of the two structures are established based on ANSYS.（2）The basic characteristics of wind are described,the average wind is represented by the exponential wind profile,the Davenport spectrum is used as the power spectrum of fluctuating wind,and the harmonic superposition method is used to simulate the fluctuating wind speed time history curve at different heights of the structure based on MATLAB programming.（3）Considering the uncertainty of the structure,the Latin hypercube sampling method is used to obtain the structure samples based on MATLAB,and the structure samples are combined with the basic wind speed to obtain multiple groups of working conditions.The wind load time history curves at different heights of the structure are obtained according to the transformation relationship of wind speed and pressure and the time history analysis under wind load is carried out for each group of working conditions,then the stress nephogram of the two structures after time history analysis is compared to find out the weak wind resistance parts of the fabricated structure,and the maximum inter story displacement angle after time history analysis is extracted to provide data source for wind disaster vulnerability analysis.（4）The performance level of the fabricated structure is selected,the story drift angle is taken as the quantitative index of the wind resistance performance of the structure and the quantitative standard is given.Multiple discrete points can be obtained by establishing the logarithmic relationship between the demand capacity ratio of the structure and the basic wind speed,then regression analysis is made on the discrete points corresponding to different performance levels.By analogy with the probability expression of seismic vulnerability,the probability expression of wind disaster vulnerability is proposed,and the vulnerability curves of structures in different failure states are drawn according to the equation and standard deviation of regression curve.