（1 华侨大学土木工程学院， 厦门 361021； 2 福建省结构工程与防灾重点实验室， 厦门 361021）

［摘要］对33个Q235钢材性试件进行单向拉伸与循环拉伸加载下力学性能试验，对比试件的应力-应变曲线、荷载-位移曲线、骨架曲线，探讨试件在不同加载模式下的破坏机理、延性特征和滞回性能。试验结果表明，Q235钢材应力-应变曲线饱满，表现出良好的延性特征；开孔试件在孔洞周围应力集中现象明显；对比无开孔试件，开孔试件的耗能能力、抗拉强度和延性大幅度降低；试件开孔个数对试验结果有一定影响，开两个孔试件的延性及抗拉强度优于开一个孔的试件；试件耗能能力与加载模式的应变幅值和滞回圈数有关，试件耗能能力随应变幅值和滞回圈数的增大而增加。

［关键词］Q235钢； 循环拉伸； 材性试验； 骨架曲线； 耗能

中图分类号：TU391文献标识码：A文章编号：1002-848X(2020)02-0107-06

Experimental study on Q235 steel with holes under monotonic and cyclic tensile loading

Xie Caixia1， Li Haifeng1,2， Lü Kunde1， Li Xia1

(1 College of Civil Engineering, Huaqiao University, Xiamen 361021, China; 2 Key Laboratory for Structure Engineering and Disaster Prevention of Fujian Province, Xiamen 361021, China)

Abstract:The mechanical properties of 33 Q235 steel specimens were tested under unidirectional tensile and repeated tensile loadings. The stress-strain curve, load-displacement curve, and skeleton curve of the specimens were compared to explore the failure mechanism, ductility characteristics and hysteresis performance of the specimens under different loading regimes. The experimental results show that the stress-strain curve of Q235 steel is full and shows good ductility characteristics; the stress concentration phenomenon is obvious around the holes of perforated specimens; compared with non-perforated specimens, the energy dissipation capacity, tensile strength and ductility of the perforated specimens were significantly reduced; the ductility and tensile strength of specimens with two holes are better than those with one hole; the energy dissipation capacity of specimens is related to the strain amplitude and hysteresis loop number of the loading regime, and the energy dissipation capacity of specimens increases with the increase of strain amplitude and hysteresis loop number.

Keywords:Q235 steel; repeated tensile loading; material properties test; skeleton curve; energy dissipation

*国家自然科学基金项目（51778248）,福建省自然科学基金面上项目（2018J01075）,华侨大学中青年教师科研提升资助计划（ZQN-PY312）,华侨大学研究生科研创新基金资助项目（17014086032）。

通讯作者：李海锋，博士，副教授，硕士生导师，Email：lihai_feng@126.com。