铁道建筑

为了准确模拟现场激励，对比现场动力学测试数据与落轴冲击试验数据，确定了落轴的轴重和落高为重要试验参数；根据测试轨道板和基础的垂向振动加速度响应等振动数据，振动传递、衰减等特性，确定了扣件减振性能评估方法及评估参数。分析了铺设不同扣件时钢轨至轨道板的振动传递率、传递函数对数幅值、振动传递损失等减振性能评估参数；结合轨道板和基础振动加速度级及垂向振动分频振级总级值的评价指标，以普通扣件为参照，对比了两类减振扣件的减振效果。结果表明：钢轨至轨道板振动传递率和传递函数对数幅值基本与扣件刚度正相关，钢轨至轨道板传递损失与扣件刚度基本呈负相关；为消除激励方式和下部基础对试验评价的影响，并考虑与现场实车测试结果的一致性，采用室内落轴冲击试验评估扣件减振性能时宜选用轨道板振动加速度级进行减振性能评估。

In order to accurately simulate on-site excitation, the wheel load and drop height of the wheel drop were determined as important test parameters by comparing the on-site dynamic test data with the wheel load drop test data.Based on the vertical vibration acceleration response and other vibration data of the test track slab and foundation, as well as the characteristics of vibration transmission and attenuation, the evaluation method and evaluation parameters for the vibration reduction performance of fasteners were determined. The vibration reduction performance evaluation parameters such as the vibration transmission rate, logarithmic amplitude of the transfer function, and vibration transmission loss from the rail to the track slab were analyzed when laying different fasteners. Based on the evaluation indicators of the acceleration level of track slab and foundation vibration, as well as the total level value of vertical vibration frequency division, the vibration reduction effect of two types of vibration reducing fasteners was compared with that of ordinary fasteners. The results show that the vibration transmission rate and logarithmic amplitude of the transfer function from the rail to the track slab are generally positively correlated with the stiffness of the fasteners, while the transmission loss from the rail to the track slab is generally negatively correlated with the stiffness of the fasteners. In order to eliminate the influence of incentive methods and lower foundations on the evaluation of the test, and to consider consistency with the results of on-site actual vehicle testing, it is advisable to use the track slab vibration acceleration level for evaluating the vibration reduction performance of fasteners when using indoor wheel load drop testing.