动车低速脱轨的动态响应

在动车轴箱下方安装防护装置, 进行线路低速脱轨试验。车辆借助脱轨器完成脱轨, 利用应变片、加速度和位移传感器采集脱轨车辆的动态响应, 采用高速摄像仪和视频摄像仪分别记录了脱轨车辆的运动姿态。基于试验数据, 评估了脱轨条件下钢轨抗倾翻能力, 验证了脱轨安全防护装置的性能, 分析了动车脱轨后的动态响应和脱轨速度、车辆质量和线路对动态响应的影响。试验结果表明: 当动车低速脱轨时, 防护装置撞击钢轨的最大横向力为177.18kN, 小于钢轨横向抵抗力510.00kN, 因此, 脱轨安全防护装置可以扣住钢轨外侧, 有效限制脱轨车辆的横向移动。车辆的脱轨过程分为惰行、轨上运动、落地和路基滑行4个阶段, 各阶段的动态响应均随脱轨速度和车辆质量的增大而增大。当动车脱轨速度为22km·h^-1时, CRTSⅡ型双块式无砟轨道的脱轨距离约为15.80m, CRTSⅠ型板式无砟轨道的脱轨距离约为20.87m, 因此, CRTSⅡ型双块式无砟轨道的轨枕可以起到减速带的作用, 减小脱轨距离。

Dynamic responses of motor vehicle in low-speed derailment

The low-speed derailment experiment of signal motor vehicle with post-derailment safety device under axle box was carried out.The derailer was installed on the rail to force the vehicle to derail.Acceleration sensors, displacement sensors and strain gauges were used to detect the dynamic responses of derailed vehicle.The motion attitude of derailed vehicle was recorded by using high-speed cameras and surveillance cameras.According to the test data, the ability of overturning resistance for rail and the performance of derailment safety device were verified.The dynamic responses of derailed vehicle and the effects of derailment speed, vehicle mass and track on the responses were studied.Test result indicates that in low-speed derailment, the biggest lateral force between rail and post-derailment safety device is 177.18 kN that is less than the lateral resistance of 510.00 kN, so the post-derailment safety device has the ability to limit the lateral displacement of derailed vehicle by catching the outside of rail after derailment.The derailment process is divided into four stages, including idling, running on the derailer, falling and coasting on the track, at which the dynamic responses of derailed vehicle are increasingwith the increase of derailment speed and vehicle mass.When derailment speed is 22km·h-1, the derailment distance of CRTSⅡ bi-block sleepers ballastless track is about 15.80 m, while that of CRTSⅠ slab ballastless track is about 20.87 m.Accordingly, the bi-block sleepers of CRTSⅡ bi-block sleepers ballastless track resemble the speed bump and decrease the derailment distance.