钢桥面铺装修复界面疲劳特性试验

为研究钢桥面沥青铺装坑槽病害修复界面的疲劳性能，定量评价病害修复界面的修复效果，采用改进的Overlay Tester试验方法进行钢桥面铺装材料疲劳断裂试验。选取完好的Overlay Tester试件、含有初始裂缝的Overlay Tester试件和切割后进行黏接的Overlay Tester试件3种状态，分别采用传统的评价标准（荷载降低93%）、特定周期数和荷载降低75%三个评价标准进行分析，试验过程中采用高清视频记录裂缝扩展过程。建立基于荷载-周期曲线的疲劳方程，分析了疲劳破坏特征及裂缝扩展过程，提出了裂缝扩展速率、疲劳断裂能和裂缝完全贯穿时的周期3个量化评价指标。研究结果表明：不同状态下Overlay Tester试件的荷载-周期均呈幂函数关系；修复界面疲劳断裂过程复杂，微观层面的集料形状对裂缝扩展的路径有显著影响；考虑疲劳过程的疲劳断裂能和裂缝完全贯穿时的周期2个指标修复效果小于表征单次加载断裂的裂缝扩展速率计算的修复效果，更符合实际工程应用效果。

Experiment for Fatigue Performance of Repaired Interface on Steel Deck Pavement

In order to understand fatigue performance of the repaired interface on steel deck pavement, and quantified evaluation of repaired interface is presented, and improved Overlay Tester as a new test method is proposed to evaluate fatigue performance of steel deck pavement. Intact specimen, specimen with initial crack and repaired specimen are adopted, and 93% reduction of the maximum load, specific cycles and 75% reduction of the maximum load, the three standards are respectively applied, and crack propagation is observed utilize by high-definition video. Fatigue Equation is established based on load-cycle; failure characteristics and crack propagation are studied; crack propagation rates, fatigue fracture energy and cycles when crack running through specimen completely, three quantitative standards, are proposed. The results show that curves of load-cycle is power function for three kinds Overlay Tester specimens; fracture process of repaired interface is complex, and aggregate shape has an effect on crack propagation path; quantified evaluation used by both of fatigue fracture energy and cycles when crack running through specimen completely is much less than crack propagation rates resulting from single load, which is correspond with effects in the field.