Dynamic Analysis Of Y Style Eccentrically Braced Steel Frame And Research On Link Beam Parameters

In this paper, the main categories of braced frame were introduced at first, the shapes and characters of centrically braced steel frame(CBSF) and eccentrically braced steel frame(EBSF) were described. The researches and developments of EBSF were discussed both domestic and abroad in detail. Then the mechanical features and power-wasting theory of EBSF were represented, and the establishment of China's criterion was told. On the basement of theory of finite element, an EBSF model were created under the earthquake action.Following this work, a profound study of Y-shape EBSF was made. Through parameters changing, the relationship between the power-wasting ability of Y-shape EBSF and some parameters was analyzed, such as length of link,height-thickness ratio of web or width-thickness ratio of flange plate. There is a big influence of length of link. When the length of link is between a = 0.9M_p/V_p～a = 1.3M_p/V_p,EBSF has the best effect. The height-thickness ratio of web is also very important, it's better for the resistance of earthquake to make the ratio to be 40 to 55. However, the width-thickness ratio of flange plate has little impact on the results. Each parameters influence level to earthquake response , is that , length> height-thickness ratio> width-thickness ratio. That is to say , the length of link is the most important parameter , while width-thickness ratio is the least important one . Compared with these , the parameter of height-thickness ratio has some function for reducing the earthquake response.