Isolators have become more attractive to researchers and industries alike over the past decade. Nonlinear stiffness for the rubber isolator is designed in the floating slab system to obtain or maintain the desired natural frequency. According to the vibration mechanics theory, the natural frequency formula can be deduced backward to obtain the function of stiffness. This then yields a simple integral equation which can be reduced and solved as an ordinary differential equation. The results demonstrate that using the nonlinear isolator can keep the frequency unchanged in a small range. However, if an isolator with linear stiffness is used, the frequency value of the new multi-degree of freedom system would not be close to the desired or designed value. By analysis of the different loading conditions for Chengdu metro, the nonlinear isolator is suitable for the non-overload condition of the vehicle. Finally, the wheel load drop test proves the good consistency between experimental results and theoretical prediction.

中文翻译：

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铁路隔离器保留基频分析和测试

在过去的十年中，隔离器对研究人员和行业越来越有吸引力。在浮动平板系统中设计橡胶隔离器的非线性刚度，以获取或保持所需的固有频率。根据振动力学理论，可以向后推导固有频率公式以获得刚度的函数。这样就产生了一个简单的积分方程，可以将其简化并求解为一个常微分方程。结果表明，使用非线性隔离器可以使频率在很小的范围内保持不变。但是，如果使用具有线性刚度的隔离器，则新的多自由度系统的频率值将不会接近期望值或设计值。通过分析成都地铁的不同装载条件，非线性隔离器适用于车辆的非过载条件。最后，车轮载荷下降试验证明了实验结果与理论预测之间的良好一致性。