Analysis Of Seismic Performance Of A New Self-Centering Rotational Friction Damper And Its RC Frame Structure

The traditional design concept of aseismic structure with the primary goal of protecting life is to dissipate seismic energy through the plastic deformation of the lateral component.Under the action of a strong earthquake,the design concept at the cost of structural components will cause the structure to lose its function due to the damage that is difficult to repair.The repair cost after the earthquake is higher,even more than the reconstruction after demolition,which will cause huge economic losses and is not conducive to the national economic construction.In order to effectively improve the seismic performance of building structures,ensure that no damage occurs or only the damage that can be quickly repaired in the event of an earthquake,and promote the transformation of the traditional seismic design concept of structures to the design concept of recoverable functional seismic structures,it is necessary to introduce selfresetting,replaceable and additional energy-consuming devices and other technologies to develop recoverable functional seismic structures.The common energy dissipation devices mainly include metal dampers,friction dampers and viscous dampers,among which friction dampers are widely used in practical projects because of their low price,stable performance and small influence of ambient temperature.At the present stage,the self-resetting components include prestressed reinforcement,shape memory alloy(SMA)and disc-shaped spring,among which prestressed reinforcement is widely used,but there are some defects such as tension and prestress loss.Disc-shaped spring requires complex structures to provide the resetting force,which requires high installation accuracy and low construction efficiency.As a superelastic material,SMA has good self-resetting characteristics and has a certain application prospect.The common self-centering components are prestressed tendons,shape memory alloy(SMA)and disc springs.Among them,prestressed tendons are widely used,but there are defects such as anchoring difficulties,excessive tension and prestress loss.Disc springs need to use more complex structures to provide reset force,with high installation accuracy and low construction efficiency.SMA is a hyperelastic material,which has good self-centering characteristics and has certain application prospects.In this paper,a new self-resetting Damper(SRD),which is composed of a rotary Friction Damper and SMA bolt,is proposed to enhance the damper performance of structures.The main research work is as follows:(1)Using SMA bolts as self-centering devices,a SRD damper composed of four self-centering rotating friction blocks is proposed,and its basic structure and working principle are clarified.Based on the constitutive model of SMA bolts,the momentrotation restoring force model of a single self-centering rotational friction combination block is derived through theoretical analysis,and then the force-displacement restoring force model of SRD damper is proposed.(2)The finite element analysis software ABAQUS is used to simulate the SRD damper.The results show that the calculation results of the restoring force model are in good agreement with the finite element analysis results,which confirms the correctness and rationality of the proposed restoring force model.The mechanical properties of the damper under different outer groove angle,friction coefficient,SMA bolt preload and SMA bolt weakening section diameter are analyzed.(3)The SRD damper is implanted into the RC frame structure to form the SRD-RCF structure,and the structure is designed by the direct displacement-based seismic design method.Under the action of three sets of seismic waves,the nonlinear time-history analysis of RCF structure and SRD-RCF structure is carried out based on Open See analysis platform,and the seismic performance is evaluated from the aspects of displacement response,interlayer displacement angle,residual deformation and energy dissipation.The results show that the SRD-RCF structure with SRD damper has better self-centering effect and energy dissipation effect,which verifies the superiority of its damping performance and provides a reference for the development and design of RC frame structure with recoverable function.