Seismic Performance And Replaceability Evaluation Method For Hybrid Frame Replaceable Beams

With the development of the seismic concept of engineering structures,the structure is required to function recoverable from the anti-collapse.There are many ways to achieve a recoverable functional structure,and a structure with replaceable components is one of the main forms to achieve structural function recoverable.In order to satisfy the needs of structural system functional recoverability after earthquake.The research group proposed an RCS hybrid frame structure with replaceable components,which is to install a small span of energy-consuming steel frame in the anti-lateral force unit of the original composite frame structure.Plastic deformation of replaceable beams dissipates seismic energy under earthquake action,but its seismic performance and mechanical properties have not been studied yet.In this paper,ABAQUS numerical simulation is used to study the seismic performance and replaceability evaluation method of replacable beam in hybrid frame structure.The main contents and conclusions are as follows.?1?The expected performances goal and design principles are proposed for the RCS hybrid frame structure replaceable components,and a typical RCS hybrid frame structure with replaceable beams is designed and statically pushed.The results show that the structure has a significant yielding moment and the main lateral stiffness is provided by the energy consuming frame,and expected performance goals can be achieved.By changing the length of replaceable beams,it is found that the length of replaceable beams has some influence on the failure mode of replaceable beam and the base shear of energy dissipation frames.?2?Considering the length coefficient of replaceable beams,the spacing of stiffeners and the connection mode of replaceable beams to columns,three groups of twenty specimens were designed and analyzed by finite element method.The seismic performance of replaceable beams in hybrid frames was studied.The control parameter l/?M_p/V_p?of the shear yielding hybrid frame replaceable beam is proposed to be 1.45 by analyzing the influence of length factor on the failure process,failure mode.The replaceable beam length factor is recommended to be designed from 0.9 to 1.2 by analyzing the influence of length factor on the hysteretic behavior,energy dissipation capacity,shear capacity and deformation capacity of the replaceable beam.Based on the shear yielding replaceable beam,the influence of the stiffener spacing on the failure process and seismic performance is analyzed.The results show that when the stiffener spacing exceeds the required value of the specification,the replaceable beam web is buckling earlier and its deformation capacity is significantly affected.Therefore,it is recommended that stiffener spacing of shear yielding replaceable beam be set according to the specifications.Simultaneously,the influence of the connection method on the seismic performance is analyzed.The results show that the connection method has great influence on the deformability of the replaceable beam.This paper suggests that the replaceable beam-column is connected by T-shaped steel.?3?Based on determining the inter-layer displacement angle of the replaceable stage of the structure from 1/300 to 1/67.The evaluation indicators of the replaceability of the replaceable beam were proposed,which are residual interlayer displacement angle?_ree and residual rotation angle of replaceable beam end?_re.By analyzing the residual deformation of shear specimens under different length factors and three connection modes,the control value of the two indicators can be obtained.That is,when residual interlayer displacement angle is less than 0.0045 rad and residual rotation angle of replaceable beam end is less than 0.0052rad,the replaceable beam is considered replaceable.Based on the evaluation indicators,an evaluation method for replaceability of replaceable beams is further proposed.And based on the analysis results of various parameters and residual deformation analysis,the design suggestion and method of replacable beam section and connection are proposed.