Study On Seismic Performance Of Rc Frame Damping Stairs

As a new energy-dissipation and shock-absorbing staircase,the staircase with damping support eliminates the diagonal bracing effect of the slab,and the stairs are caused by the earthquake through the joint action of the spring unit,and the damping unit in the damping support.The excessive restraint effect of the inter-structure on the building structure which improves the seismic performance of the staircase structure and its main structure,and ensures the relatively complete function of the staircase structure in earthquakes.In this paper,the damping performance of the staircase with damping support and the effect of design parameters on its damping are compared.The damping support that is also a viscous damper is compared as a comparison.Pros and cons,the main research contents are as follows:1)Designing the corresponding staircase finite element model for static loading,and comparing and analyzing the stress characteristics of each modelThe finite element software was used to perform monotonic static loading on the three staircases with damped support staircase,damped support staircase and ordinary staircase.The force characteristics and performance forms of these three staircases were compared to study their shock absorption performance..The damping effect is particularly significant in the translational period in the Y direction.The staircase structure with damping support and the staircase structure with damping support are reduced by 34.21% and 1.40% compared with the ordinary staircase structure.The results show that the damping support and the damping support reduce the diagonal bracing effect of the slab to varying degrees compared to the ordinary stairwell,especially the staircase with damping support also improves the force transmission mechanism of the staircase,So that the structural members of the staircase are protected,and the adverse effects of the staircase on the frame beams and columns are avoided.2)Comparative study of the effects of viscous damper parameters on the seismic performance of the stairwellA total of 14 models of three schemes were adopted for the setting of viscous dampers,and the finite element analysis was carried out for each stairwell model adopting these three schemes,and the effects of different viscous damper setting schemes on the seismic performance of the staircase were compared.The results show that the use of viscous damping support will increase the initial stiffness of the staircase structure and weaken the ductility of the staircase structure,which is not conducive to the damper’s effect of energy dissipation and shock absorption.The number of seats is proportional to the ductility of the structure,but at the same time,the bearing capacity of the structure and the limit of interlayer displacement must be considered to control the number of viscous damping bearings;with the shear strength of the elastic layer of the viscous damping bearings Increase,can increase the initial strength of the staircase and the peak load in the yield stage,reduce the yield displacement of the staircase,and also reduce the ductility of the staircase,so whenchoosing the shear strength of the elastic layer,the shear mode is recommended The amount of elastic layer material is about 0.4MPa,which can not only ensure the bearing capacity of the structure,but also provide considerable hysteretic energy consumption performance.3)By inputting seismic time-history waves,comparative analysis of RC damping staircase’s performance of shock absorption and energy dissipationUsing SAP2000 and pkpm finite element analysis software to establish a staircase frame structure with damping support,a staircase frame structure with damping support,a common staircase frame structure and an empty frame structure,a total of 4 models are input.Seismic waves and rare earthquake waves,check the interlayer shear force,interlayer displacement,axial force of stair components and the dissipation capacity of seismic energy of each model,and conduct a comparative analysis to study the damping of the staircase frame structure with damping support Energy dissipation performance.The results show that the staircase structure with damping support exerts a strong energy dissipation effect,provides the structure with a certain effective damping ratio,and at the same time reduces the floor shear force of the structure,improves the floor displacement,and increases In the second floor where the displacement occurred,the staircase with damping support,the staircase with damping support and the ordinary staircase were reduced by 8.96%,11.31% and 21.35% compared to the empty frame structure.The stairwell with damping support embodies better ductility.Under the action of rare earthquakes,the additional damping ratio of the structure is greater than5%,and the total damping ratio of the structure is greater than 10%,indicating that the staircase structure with damping supports can effectively delay the yield of the stair beam and reduce the frame beam The degree of damage reduces the seismic energy input to the frame structure.