摘要
采用落锤冲击试验机进行了4个T形管节点的抗冲击性能试验研究。通过试验获得了冲击能量E、主管长径比(α=L/D)和主管直径D等参数对管节点破坏模态和变形模式的影响规律,分析了管节点在冲击力作用下整体和局部变形特性,以及冲击力、位移、应变时程曲线与冲击力-变形关系曲线。试验结果表明:主管长径比一定时,冲击能量的大小影响支管受撞T形管节点的破坏模态;破坏模态主要为主管上表面局部屈曲和主管上表面局部屈曲伴随主管整体弯曲变形两种形式;主管上表面局部屈曲产生的塑性变形区域受冲击力的影响不大,但其屈曲凹陷深度随着冲击能量的增大而增大;局部屈曲耗散了大部分冲击能量。基于能量的塑性铰线理论,提出了等效冲击承载力简化评估方法。
Drop weight setup was used to experimentally study the impact behavior of four tubular T-joints. The effects of impact energy （E） , length-diameter ratio （α = L/D） and diameter of chord on the dynamic failure modes were obtained. The global and local buckling characteristics of tubular T-joints under impact loading were discovered. The measured impact force, displacement, strain history curves, impact load versus deformation relationship curves were studied. The experimental results show that when the length-diameter ratio is constant, the failure modes of tubular T-joint are determined by the impact energies. The chord tubes of the T-joints under impact loading at the brace end suffered remarkable local buckling and flexural folding, while no obvious overall flexural deformations of the chords. The area of plastic zone of the chord generally does not change with the increase of impact energy. However, the depth of plastic zone obviously increases with the increase of impact energy which generally is absorbed by the local buckling of steel tube. On the basis of the yield line theory, simplified predicted method is put forward.
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2013年第4期65-73,共9页
Journal of Building Structures
基金
国家青年科学基金项目(51108399)
山东省高等学校科技计划项目(J11LE11)
建筑安全与节能教育部重点实验室(湖南大学)开放基金项目(2012001)
关键词
T形管节点
冲击试验
破坏模态
局部屈曲
抗冲击机理
tubular T-joint
impact test
failure mode
local buckling
impact resistant mechanism
