扩孔螺栓连接型消能梁段的耗能机理及设计方法研究

Energy dissipation mechanism and design method of an innovative SSL-SSBC

罕遇地震下,偏心支撑结构需合理有效地增大消能梁段的延性和耗能能力,并减小消能梁段的变形,以有效提高该种结构的抗震性能和震后功能快速恢复能力。本文基于短剪切型消能梁段和剪切扩孔型螺栓连接的力学性能,提出一种扩孔螺栓连接型消能梁段。采用校正的数值分析方法对扩孔螺栓连接型消能梁段进行详细分析,以明确扩孔型螺栓连接和短剪切型消能梁段力学性能的相互影响,揭示其耗能机理,并建立相应的设计方法。研究表明,所提出的扩孔螺栓连接型消能梁段的耗能能力有明显提高,且在达到预期性能时有效减小短剪切型消能梁段的变形和损伤,有效提高了构件的震后功能恢复能力,由此为偏心支撑结构的抗震设计提供新的思路和方法。

Under severe earthquakes,effective energy dissipating capacity of shear links with higher ductility and low damage is currently in higher demand to ensure the seismic safety,so the eccentrically braced frames(EBFs)can better meet the higher demand in new Code for Seismic Design of Buildings.In this study,a new type of very short shear link with shear slotted bolted connections(SSL-SSBC)is developed,which combines the excellent mechanical properties of very short shear link and shear slotted bolted connection(SSBC).The numerical models of very short shear link and SSBC are firstly verified by comparison with existing experimental results.Then,the models of SSL-SSBC with different influencing factors will be accurately analyzed,so the mechanical performance of SSL-SSBC will be evaluated,and the mutual performance influence of SSBC and very short shear link in SSL-SSBC can be investigated in detail.Also,the energy dissipation mechanism and a new design method of SSL-SSBC can be revealed and proposed,respectively.The results indicate that the seismic performance of EBFs with an innovative SSL-SSBC can be dramatically improved,and the deformation and damage of very short shear link in SSL-SSBC can be significantly decreased,so the seismic resilience capacity of new SSL-SSBC will be effectively improved.In addition,the new SSL-SSBC also provides a new way to give important seismic design reference for EBFs.