正交异性钢桥面板应用广泛、但疲劳问题也较多,特别是与U肋相交的横隔板弧形缺口位置较为严重,各国规范和工程实践做法迥异。为研究弧形缺口边缘的2个主要疲劳开裂热点,选取4种不同缺口形式,考虑横隔板间距与厚度、肋高、缺口间隙等4种尺寸参数,建立桥面板局部空间模型进行分析,结合热点应力法进行疲劳评估。结果表明:对于这些缺口构造形式,与疲劳性能密切相关的热点应力水平和几何应力集中系数均表现出对各尺寸参数的显著相关性;不同缺口构造形式适用于不同的荷载条件。综合分析结果,本文推荐了一种弧形缺口形式,各项计算指标均较好。
Lots of fatigue problems of arc-shaped cutouts on diaphragm appear in widely used orthotropic steel deck plates, especially the position s with the intersection of U rib is more serious, while there are different approaches in dealing with it in engineering practices and different countries' specifications. For the study of the two major hot spots of fatigue cracking on the edge of cutouts, on the basis of four kinds of arc-shaped cutout, a numerical spatial analytical model of deck plate was set up considering the spacing and thickness of diaphragms , the rib high and the gap of cutouts. And then, fatigue evaluation was conducted in combination of hot spot stress method. "The result shows that ( 1 ) the stress levels and geometry stress concentration factors of the hot spots which closely related to the fatigue properties presented significant correlation to the various size parameters for all cutouts; (2) different forms of cutout are suitable for different load conditions. From the comprehensive analysis of the result, a rational form of arc-shaped cutout which shows good stress distribution was recommended.