面内预起拱型梁端地震损伤控制保险丝力学性能试验研究

EXPERIMENTAL STUDY ON THE MECHANICAL PROPERTY OF IN-PLANE PRE-ARCHING SEISMIC DAMAGE-CONTROL FUSES FOR BEAM-TO-COLUMN CONNECTIONS

  • 摘要: 工程结构抗震韧性的提升是城市韧性建设的基础。研究具有“保险丝”损伤熔断、损伤可识别、易更换理念的新型结构地震损伤控制构件,对结构体系抗震韧性水准的提升具有重要价值。在前期常规平板型损伤控制保险丝研究的基础上,该文提出了一种利用面内预起拱机制进行梁柱节点损伤控制的保险丝装置。阐明了建议的结构损伤控制保险丝装置(简称保险丝)的构造与工作机理。设计了6个不同预起拱情况、不同长细比的保险丝试件,并采用拟静力加载方式对保险丝的受力机理与抗震性能进行研究。对试验结果的分析发现:与平板保险丝相比,面内预起拱型保险丝的滞回曲线更饱满,受压强度更稳定;预起拱延缓了强度退化;随着长细比减小或预起拱高度的增大,强度退化变缓;分肢转角超过0.07 rad左右时,保险丝受损导致强度逐渐下降,建议对其进行更换。力学模型计算结果与试验结果基本吻合,可估算预起拱型保险丝特征强度。

     

    Abstract: Improvement of the structural seismic resilience is fundamental to city resilience construction. It is important to improve the seismic resilience level of structures based on developing structural seismic damage-control elements with functions, including damage-free, damage identification and replaceability. Based on previous study on conventional flat-plate fuses, an innovative pre-arching fuse is proposed to control the damage of beam-to-column joints through in-plane pre-arching mechanism. The configuration and working mechanism of pre-arching fuses were described. Six sets of pre-arching fuses with different pre-arching conditions and slenderness ratios were designed, and the mechanical mechanism and seismic performance were studied by pseudo-static tests. The test results show that the pre-arching fuses exhibited more stable compressive strength and full hysteresis loops than the flat-plate fuses. The strength degraded more slowly for pre-arching fuses with smaller slenderness ratio and larger pre-arching height. When the compressive rotation of split pier exceeded about 0.07 rad, the strength of pre-arching fuses decreased, which can be suggested as a criterion for replacement. A mechanical model was proposed to estimate the yielding and maximum strength of the pre-arching fuses.

     

/

返回文章
返回