一种新型防屈曲-分阶段耗能剪切型阻尼器及其性能分析

A new type of anti-buckling stage energy dissipation shear damper and its performance analysis

为解决传统剪切型金属阻尼器耗能形式单一,剪切腹板易过早发生局部屈曲的问题,设计了一种新型防屈曲-分阶段耗能剪切型阻尼器。该阻尼器主要由剪切腹板和防屈曲耗能件组成,防屈曲耗能件分布于剪切腹板两侧,上下两端与固定架相连。为考察其耗能和防屈曲能力,本文以传统的剪切型阻尼器试验模型为参考,利用ABAQUS有限元分析平台建立了14组阻尼器数值模型,分析了防屈曲耗能件的截面形状、使用材料的类型及与固定架间的连接方式等对阻尼器性能的影响,并采用刚度退化系数和等效黏滞阻尼比为评价参数衡量新型阻尼器的抗震性能。结果表明,设置了防屈曲耗能件的新型阻尼器其剪切腹板的最大面外位移与传统阻尼器的比值低于1/4,防屈曲耗能件与剪切腹板的最大屈服位移比超过3∶1,可以有效防止剪切腹板过早发生屈曲,具备多阶段耗能的能力。相比于传统无防屈曲耗能件剪切型阻尼器,此类阻尼器耗能能力强、滞回性能稳定、具备较好的抗震性能,可以满足实际工程结构的抗震设计要求。

In order to solve the problem that the traditional shear-type metal damper has a single form of energy dissipation and the shear web is prone to premature local buckling,a new type of anti-buckling and staged energy dissipation shear damper is designed.The damper is mainly composed of a shear web and anti-buckling energy dissipation parts.The anti-buckling energy dissipation parts are distributed on both sides of the shear web,and the upper and lower ends are connected with a fixed frame.In order to investigate its energy dissipation and buckling resistance,the traditional shear damper test model is taken as a reference in this paper,and 14 groups of numerical models are established by ABAQUS finite element analysis platform.The effects of the section shape of the anti-buckling energy dissipator parts,the type of materials used,and the connection mode with the fixed frame on the performance of the damper are analyzed,and the stiffness degradation coefficient and the equivalent viscous damping ratio are used as evaluation parameters to evaluate the seismic performance of the new damper.The results show that the maximum out-of-plane displacement of the shear web of the new damper with buckling-restrained damper is less than 1/4 of that of the traditional damper.The maximum yield displacement ratio of the buckling damper to the shear web exceeds 3∶1,which can effectively prevent the premature buckling of the shear web,and thus has the capability of multi-stage energy dissipation.Compared with the traditional shear damper without the anti-buckling parts,this new type of damper has strong energy dissipation capacity,stable hysteretic performance and good seismic performance which can meet the seismic design requirements of practical engineering structures.