钢-混凝土连续组合铁路桥梁综合动力性能试验研究

Experimental Study on the Integrated Dynamic Behavior of Continuous Steel-Concrete Composite Girders of Railway Bridges

通过对某客运专线的钢-混凝土连续组合板梁铁路桥和连续组合箱梁铁路桥的综合动力性能试验,测试在高速列车通过时钢-混凝土组合连续梁桥的自振特性、动挠度、竖横向振幅、竖横向加速度、墩顶横向振幅、支座位移、脱轨系数、轮重减载率和轨道力等动力响应和安全指标。采用车桥耦合振动理论对2座组合梁桥进行动力仿真分析,对桥梁的动力性能、试验列车运营的舒适性和安全性进行预测,结合已有相关规范,分析实测资料并综合评价2种类型组合梁铁路桥体系的各种性能。试验结果表明,在高速列车荷载作用下,2座组合梁桥梁体及墩身应力增量很小,支座位移也很小;实测梁体竖向自振频率符合相应的规范要求;在高速列车荷载作用下,梁体跨中挠度、横向振幅、竖横向加速度和墩顶横向振幅以及桥梁中跨跨中的脱轨系数、轮重减载率和轨道力符合相应的规范要求。

This paper presents an experimental study on the integrated dynamic behavior of continuous steel-concrete composite plate girders and composite box girders on the special passenger railway in China. The behavior of the bridges under high-speed passenger trains such as natural vibration, dynamic deflections, lateral and vertical amplitudes, lateral and vertical accelerations, lateral pier amplitude, bearing displacement, derail coefficient, wheel load reduction ratio, and track force were tested. The dynamic response of two bridges were simulated through applying coupling vibration analysis theory, and the dynamic behavior of bridges, the safety and comfortableness of trains running on the bridges were predicted. Combined with corresponding codes, the behaviors of two new type steel-concrete composite girders were evaluated from test results and calculated results. Experimental results show that under high-speed passenger trains, the stress increment of the bridges and piers, and the bearing displacement of bridges are small. Analysis results show that the vertical frequency of free vibration accords with Code for Rating Existing Railway Bridges. Under the load action of high-speed passenger trains, the deflections, lateral amplitudes, lateral and vertical accelerations, lateral pier amplitude, derail coefficient, wheel load reduction ratio, and track force of bridges meet corresponding codes.