| Structures have certain ductility capacity and energy dissipation capacity, when entering into plastic stage during intense ground shaking. The modern seismic design theory discount the elastic response spectrum of seismic fortification intensity scale by structural influencing coefficient R to obtain the action of structural seismic design, then design the structural by elastic design methods.Current Chinese "Code for Seismic Design of Building" (GB50011-2001) adopt the value (0.35) of seismic influencing coefficient R which is based on the concrete structure in the way of "elastic design of small earthquake level".The rational factors of different value of structural influencing coefficient are based on the structures or components of different ductility were ignored. Compared with the concrete structure,the design seimic base shear force of steel structure is not only lower for the good capacity of energy disspation and ductiliy, but also the force is larger for the lower damping value of steel structure, which isn't conducive to the development of steel structure.Based on elastic-plastic time-history earthquake analysis of dog-bone connection steel frame, the ductility reduction factor Rμ,the structural overstrength factor RΩand the structural influencing coefficient R of dog-bone connection steel frame were investigated for different stories and spans. It is found that the ductility reduction factor of dog-bone connection steel frame is larger than that of the common joint connection steel frame, the former structural overstrength factor is smaller than the latter, and the difference of the structural influencing coefficient between them is slight, which illustrate that the application of dog-bone connection to steel frame do not change the value of the structural influencing coefficient R.
|
PDF Full Text Request