浮置板轨道系统动力响应分析

Analysis of Dyanmical Responses of Floating Slab Track System

研究目的：随着交通密度的不断增加，荷载不断加重，车速不断提高，交通引起的振动对城市生活环境和工作环境产生极大的影响，交通引起的振动已经成为环境公害。浮置板轨道系统具有良好的减振性能，因而在工程中获得了广泛的应用。研究方法：建立浮置板轨道结构双层连续弹性梁模型，用傅里叶变换法并且借助MATLAB软件编制程序求得了轨道结构的振动响应，得到了传递到地面的最大激振力与激振频率的关系曲线，分析了浮置板弹性支撑刚度、阻尼及浮置板的单位长度质量对浮置板轨道系统减振效果的影响。研究结果：得到了浮置板弹性支撑刚度的合理取值范围为6～30MN／m，浮置板支撑阻尼的合理取值范围为40～80kN·s／m，及浮置板的单位长度质量的合理取值范围为2000～4000ks／m。研究结论：浮置板轨道系统对较高激振频率的振动有很好的减振效果，浮置板弹性支撑刚度的取值越小浮置板减振效果越好。

Research purposes： With the increase of traffic consistency and load and speed, the vibration aroused by the traffic has brought a huge effect to the city＇s life and work environment, the vibration aroused by the traffic has brought environment social effects of pollution. Floating slab track system has all right performance of vibration reduction, it is widely used in engineering. Research methods： Establish double layer continuous viscoelastic beam model of floating slab track structure, the vibration responses of the track structure are obtained with application of compiled programs by Fourier transform and making use of a software MATLAB, and we gained maximum forces transmitted to the ground - frequency curses. Besides influences of elastomeric bearing rigidity and damping below the floating slab, unit length mass of floating slab on the effectiveness of the floating slab track system are investigated. Research results： We gained that the reasonable range of elastomeric bearing rigidity below the floating slab is in the range of 6 -30 MN/m, choose the value of elastomeric bearing damping below the floating slab in the range of 40 80 MN/m, and choose the value of unit length mass of floating slab in the range of 2 000 - 4 000 kg/m. Research conclusions： Floating slab track system has a very good effect of vibration reduction on the high frequency vibration, and the less the value of elastomeric bearing rigidity below the floating slab is, the better the effect of vibration reduction is.