单跨双线铁路曲线桥梁车桥耦合振动特性分析

为了研究单跨双线铁路曲线桥梁车桥耦合振动特性,建立车桥耦合振动模型,对列车通过单跨曲线桥(半径为600 m)内线和外线时,各板件的振动情况及影响最大的主频进行仿真计算,通过对比分析,得出与单跨直线桥的振动特性差异,为后期的单跨曲线桥结构减振处理及连续曲线桥梁(半径为600 m)研究提供理论参考。结果表明:相同条件下,顶板跨中结构位移方面,曲线桥(外线行驶)>曲线桥(内线行驶)>直线桥。顶板振动加速度方面,曲线桥(外线行驶)>曲线桥(内线行驶)>直线桥。但是在两侧板、底板振动加速度方面,曲线桥(内线行驶)>曲线桥(外线行驶)>直线桥。相比直线桥,曲线桥产生的低频振动更大,振动加速度对应的主频也较多,引起的低频噪声也更大。由于横向力的影响,桥梁结构稳定性还会受到一定的影响。

Analysis of Vibration Characteristics of Double-track Railway Curved Bridge

In order to study the coupling vibration characteristics of curved bridges and bridges of single-span double-track railway, this paper establishes the coupled vibration model of the vehicle and bridge to simulate and calculate the vibration and the largest main frequency of each plate when the train passes through the inner and outer lines of a single-span curved bridge(with a radius of 600 m). Through comparison and analysis, the vibration characteristic difference of the single-span linear bridge is obtained, which provides a theoretical reference for the study of the single-span curve bridge structure damping treatment and the continuous curve bridge(radius 600 m). The results show that under the same condition, the displacement of the roof mid-span structure of curve bridge(outside line travel) > that of curve bridge(internal line travel) > that of linear bridge, and the vibration acceleration of the roof of the curve bridge(outside line travel) > that of curve bridge(internal line travel) > that of straight line bridge. However, in terms of vibration acceleration of the plates on both side and the bottom plate, the curve bridge(internal line travel) > curve bridge(external line travel) > linear bridge. Compared with the linear bridge, the low-frequency vibration generated by the curved bridge is larger, and the corresponding main frequency of the vibration acceleration is also larger with bigger low-frequency noise. Due to the influence of lateral forces, the stability of the bridge structure will be affected to some extent.