热处理方钢管短柱超低周疲劳性能试验研究  

Experimental study on ultra-low-cycle fatigue performance of heat-treated steel square hollow section stub columns

作　　者：贾良玖[1] JIA Liangjiu(Research Institute of Structural Engineering and Disaster Reduction,Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学结构防灾减灾工程系,上海200092

出　　处：《建筑结构学报》2020年第8期97-104,共8页Journal of Building Structures

基　　金：国家重点研发计划项目(2016YFC0701603);国家自然科学基金青年科学基金项目(51508401)。

摘　　要：强震下钢结构构件会发生局部或整体屈曲,造成构件局部塑性应变集中,导致构件在反复荷载作用下最终发生断裂,因此有必要开展大塑性应变循环加载下局部屈曲和后续延性断裂的耦合破坏机理研究。通过热处理冷弯方钢管短柱的超低周疲劳试验,对上述破坏机理进行了研究。试验考察了宽厚比和加载历史对于方钢管短柱屈曲后断裂模式及抗震性能的影响,并给出了累积延性评估方法。试验结果显示:所有试件受压时承载力的下降皆由局部屈曲导致,而受拉侧承载力的退化则由延性断裂造成;构件的累积塑性耗能可分解为各向同性强化耗能和随动强化耗能,且两者受拉时对应值呈线性关系。For steel structural members subjected to strong earthquakes,the occurrence of local or global buckling may lead to concentrated plastic strain,which can finally trigger fracture under cyclic loading.Thus,there is a need to investigate the coupling effect of local buckling and post-buckling ductile fracture mechanism under large cyclic strain loading.In this paper,ultra-low-cycle fatigue tests on heat-treated square hollow section(SHS)stub columns were conducted to investigate the aforementioned failure mechanism.The effects of width-to-thickness ratio and loading history on the post-buckling cracking modes and seismic performance of SHS stub columns were studied,and an evaluation method for the cumulative ductility was proposed.The experimental results showed that decrease of compressive loading-carrying capacity is induced by local buckling for all the specimens,while deterioration of tensile capacity is due to ductile fracture.It was found that the cumulative plastic energy dissipation could be contributed by both isotropic hardening and kinematic hardening,and the two followed a linear relationship.

关 键 词：方钢管 超低周疲劳 延性断裂 滞回加载 抗震性能 

分 类 号：TU392.4[建筑科学—结构工程] TU317.1