摘要
该文通过不同应变幅值、不同加载频率以及疲劳荷载下的低周往复试验,对A、B两种具有不同耗能特征的黏弹性阻尼器的基本力学性能进行了研究,并对其储能剪切模量、耗能剪切模量、损耗因子等力学性能进行比较分析。试验结果表明:在相同变形幅值下,A、B两种黏弹性阻尼器的损耗因子和等效阻尼比的值比较接近,其中A种黏弹性阻尼器的单位体积材料的耗能量较大,提供的刚度也更大,但是加载过程中材料内部的升温效应比较明显,疲劳荷载下的各力学性能指标的衰减量也较大;B种黏弹性阻尼器的单位体积材料的耗能量和刚度较小,但是其力学性能受材料内部升温效应以及累积疲劳损伤的影响较小,疲劳荷载下各力学性能指标的衰减量较小。因此,在实际工程应用中,A种黏弹性阻尼器适合应用于有较高的刚度需求和耗能需求的结构,而B种黏弹性阻尼器适用于对力学性能稳定性以及抗震疲劳性能要求较高的结构。另外,采用Bouc-Wen模型得到的模拟结果与试验数据吻合良好。
Low cycle tests of A-type and B-type viscoelastic dampers are carried out with different energy dissipating characteristics,and shear storage module,shear loss module,loss factor and other parameters are compared under different strain amplitudes,under different loading frequencies and under fatigue loads.Experimental results show that the loss factor and equivalent damping ratio have little difference between two types of dampers.Besides,the A-type viscoelastic damper dissipates more energy per unit volume and has larger stiffness,but the temperature of the material increases obviously during the loading process which leads to a significant mechanical property attenuation under fatigue loading.Furthermore,B-type is less affected by heating effect of viscoelastic material and cumulative fatigue damage and has more stable mechanical performance and more excellent seismic fatigue property.Therefore,in practical structural engineering application,A-type viscoelastic damper is suitable for the structure with higher stiffness requirement and larger energy dissipation requirement,while the B-type is suitable for the structure with less stiffness requirement and more stable energy dissipation requirement.Besides,the simulated results using Bouc-Wen model are well consistent with the experimental results.
作者
周颖
刘晓芳
汪盟
ZHOU Ying;LIU Xiao-fang;WANG Meng(College of Civil Engineering,Tongji University,Shanghai 200092,China)
出处
《工程力学》
EI
CSCD
北大核心
2021年第S01期167-177,共11页
Engineering Mechanics
基金
国家自然科学基金项目(51878502)。