钢结构的主要破坏形式之一为疲劳破坏，这类破坏往往伴随着钢材的突然断裂；目前针对Q690D高强钢材的疲劳性能研究还比较缺乏。为了得到Q690D高强钢的疲劳特性曲线，本研究开展了Q690D高强钢的高周疲劳试验，根据试验的结果拟合出Q690D高强钢的应力-寿命（S-N）疲劳曲线，并与规范疲劳公式和其他强度等级钢材已有的疲劳试验曲线进行对比。试验结果表明：Q690D高强钢的疲劳性能远高于普通钢，且比美国钢结构规范（ANSI/AISC 360-10）和欧洲钢结构规范（BS EN 1993-1-9）的计算值要大，说明Q690D高强钢的疲劳性能比较优越，规范计算值偏保守；钢材的疲劳曲线与其屈服强度高度相关，且离散性很强。

One of the main failure modes of steel structure is fatigue failure, which is often accompanied by sudden fracture of steel. At present, there are little research on fatigue properties of Q690D high strength steel. In order to obtain the fatigue characteristic curve of Q690D high-strength steel, the high-cycle fatigue test of Q690D high-strength steel was carried out in this study. The S-N (stress-life) fatigue curve of Q690D high-strength steel was fitted based on the test results and compared with the existing fatigue test curves of standard fatigue formula and other strength grades of steel. The test results show that the fatigue performance of Q690D high strength steel is much better than that of ordinary steel, and is larger than the calculated values of the American steel structure specification (ANSI/AISC 360-10) and the European steel structure specification (BS EN 1993-1-9). It indicates that the fatigue performance of Q690D high strength steel is superior, and the calculated values of the specification are conservative. The fatigue curve of steel is highly correlated with its yield strength and has strong discreteness.