深圳地铁11号线橡胶弹簧浮置板轨道动力仿真及测试

深圳地铁11号线是国内首次采用橡胶弹簧浮置板轨道的地铁线路。为确保该种浮置板结构的安全性、检验其减振效果,有必要针对其动力学特性进行全面的仿真和测试。首先,通过模态分析、谐响应分析考察其固有频率、振动传递特性;然后建立车辆-轨道耦合动力学模型,对其减振效果、动态位移进行仿真模拟;最后通过实车测试,全面检测其减振效果、动态位移,以及轮轨力、脱轨系数、轮重减载率等各项动力学指标。相关理论分析及实测结果表明:橡胶弹簧浮置板固有频率为10. 5 Hz,可明显削弱频率在18 Hz以上的振动,其减振效果达13～15 d B,满足设计要求;轮轨垂向力、轮轨横向力均略小于同等条件下的普通整体道床;脱轨系数、轮重减载率均满足规范要求。以上理论研究和实践表明:橡胶弹簧浮置板结构安全、减振效果好,各项动力学指标优良,是一种较为理想的轨道减振设施。

Simulation and Dynamic Test of Rubber Spring Floating Slab in Shenzhen Metro Line 11

Shenzhen metro line 11 is the first metro line adopting rubber spring floating slab. In order to ensure the safety of the floating slab track system and test its vibration damping effect,it is necessary to carry out comprehensive simulation and test of its dynamic characteristics. Firstly,the natural frequency and vibration transmission characteristics are investigated through modal analysis and harmonic response analysis. Then a vehicle-track coupling dynamics model is established to simulate the vibration damping effect and dynamic displacement. Finally,substantial vehicle tests are conducted to comprehensively test its vibration damping effect,dynamic displacement,wheel-rail force,derailment coefficient,wheel unloading rate and other dynamic indexes. Related theoretical analysis and measured results show that the natural frequency of the rubber spring floating plate is 10. 5 Hz,and vibrations above 18 Hz can be significantly reduced by the floating slab system,and the achieved vibration damping effect of 13 ～ 15 d B meet the design requirements. The wheel-rail vertical force and lateral force are slightly less than those of the ordinary ballastless track under the same conditions. The derailment coefficient and wheel unloading rate meet standard requirements. The above theoretical researches and practices show that the rubber spring floating slab track system is safe with good vibration damping effect,and a relatively ideal track damping measure.