The Structural Influencing Coefficient Of Multi-story Steel Frames In Different Site

Various structure systems of the rational design all have the margin of safety of different degree, these structures which they can bear earthquake action are obvious greater than the earthquake loade in design. In order to simplify the earthquake-resistance design, most foreign anti-earthquake norm base the intermediate earthquake design. It makes use of the ductility and overstrength of the structure, introducing the structure influence coefficient (or be called the earthquake reaction correction coefficient) to reduce the single system elastic response spectrum in defending earthquake intensity, it can get design earthquake function of various structure system.According to the design criteria"three levels, two steps", current norm continued uses"tremor flexibility design method"that 89 norm adopted and doesn't take into the effect for the ductility of the structure. It doesn't separate the steel structure,the reinforced concrete structure and various structure systems, and takes the same earthquake function. This kind of earthquake-resistance which based tremor doesn't sufficiencily make use of good ductility and dissipative energy ability for the steel structure systems, it resulted irrationality in earthquake-resistance and steel material wasty.This paper designs 12 multiple-story steel frames according to our country《The Building Anti-earthquake Design Norm》, inputs the earthquake wave under four sites, adopts dynamic time history method to analyse the structure earthquake reaction, gets the structure influence coefficient of multiple-story steel frames, and discusses these variation of coefficients along with the structure level number and site.With expect to provide proper earthquake action for the steel structure earthquake-resistance design, to improve the present status which confines development of steel structure because of highe using the amount of steel.According to our country《The Building Anti-earthquake Design Norm》, the result indicates that for the structure influence coefficient the site influence cann't ignore. When we design in response to norm, the earthquake action value for six layers and six layers lower structure is great, suggests properly to lower.