扇形铅黏弹性消能器设计参数对加固框架抗震性能影响分析

Influence of Different Design Parameters of Sector Lead Viscoelastic Dampers on the Seismic Performance of Retrofitted Frame Structures

为研究扇形铅黏弹性消能器设计参数对加固框架抗震性能的影响,使用ABAQUS软件建立加固框架试件的精细化有限元模型,并基于试验结果验证其合理性,在此基础上,研究了扇形有效半径、黏弹性层宽度、铅芯直径3个关键设计参数对扇形铅黏弹性消能器加固框架结构抗震性能的影响及规律。分析结果表明,增加扇形铅黏弹性消能器的扇形有效半径、黏弹性层宽度、铅芯直径均可以提高加固框架的初始刚度、屈服荷载和峰值荷载;增加消能器的扇形有效半径可以显著提高加固框架的抗震性能;为避免消能器扇形有效半径过大导致梁柱局部应力集中,在既有结构加固中,扇形铅黏弹性消能器应避免选取过大的扇形有效半径;消能器的铅芯大小对加固框架的后期承载力影响不大。

To study the influence of the design parameters of sector lead viscoelastic damper on seismic performance of the reinforced frames, precise finite element model corresponding to the experimental retrofitted frame specimens was built based on ABAQUS and validated by test results. Three key parameters of sector lead viscoelastic damper influencing the seismic performance of retrofitted frames were studied: sector effective radius, viscoelastic layer width and lead core diameter. Analysis results indicate that increases of sector effective radius, viscoelastic layer width and lead core diameter of sector lead viscoelastic damper can significantly enhance the initial stiffness, yielding force and lateral bearing capacity of the retrofitted frames. In particular, augment of sector effective radius reveals an obvious raise on seismic performance of the retrofitted frames. However, to avoid local stress concentration of columns and beams, an exaggerated sector effective radius shall be avoided when strengthening existing structures. Furthermore, the size of lead core diameter of sector lead viscoelastic damper has little contribution on the later bearing capacity of the reinforced frames.