| The structure system of eccentrically braced frames has been widely accepted and used.Y-eccentrically braced frame has excellent horizontal bearing load capacity,lateral stiffness and energy dissipation capacity.It's a good structure system of eccentrically braced frame.However,it will cause some damage to the beam and floor under the horizontal earthquake.A concentrically braced steel frame filled with core steel frame has been built in this paper in order to avoid the damage of link on beam and floor under horizontal seismic action.In order to investigate the seismic performance of concentrically braced steel frames filled with core steel frame,some researches have been carried out in this paper as follows:(1)A 3 span and 12 storey concentrically braced steel frame filled with core steel frame has been designed and analysed.The design formula of core steel frame section and the reasonable range of core steel frame are put forward.(2)A finite element model with damage criterions of steel frame embedded cross shape brace with link beam experimental specimen were established with finite element software ABAQUS in order to verify the reliability of finite element simulation method in this paper.The finite element numerical simulation results are in agreement with the experimental results.(3)A 1 span and 1 storey concentrically braced steel frame filled with core steel frame has been selected from the model frame as the BASE specimen.The finite element model of the BASE specimen were established and numerical analysed.Then the design parameters of core steel frame have been changed to research the influence on hysteretic behavior of the BASE specimen.The results show that the core steel frame section size,the web height of link beam and the web thickness of link beam acquire great influence on hysteretic behavior of the BASE specimen.(4)The steel strength of the beams?columns and braces of the BASE specimen have been changed in order to research the influence on hysteretic behavior of the BASE specimen.The results show that the higher the strength of the beams?columns and braces of the structure,the greater the horizontal bearing capacity and the lateral stiffness of the structures are,and the weaker the energy dissipation capacity is.(5)The finite element models of a Y-eccentrically braced frame and a steel frame embedded cross shape brace with link beam were established to carry out the nonlinear numerical analyses for they hysteretic behavior.And the numerical analyses results were compared with the results of the BASE specimen.The results show that the concentrically braced steel frame filled with core steel frame can not only avoid the damage of the beam under horizontal earthquake,but also have high horizontal bearing capacity,lateral stiffness and energy dissipation capacity. |
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