Sun Liangming, Liu Shuguang, Kong Fan, Zhao Hanbing
School of Civil Engineering and Architecture, Wuhan University of Technology, 122 Luoshi Road, Wuhan 430070, China.
Hubei Key Laboratory of Roadway Bridge and Structure Engineering, Wuhan University of Technology, 122 Luoshi Road, Wuhan 430070, China.
Materials (Basel). 2024 Sep 13;17(18):4491. doi: 10.3390/ma17184491.
To provide a theoretical basis for eliminating resonance and optimizing the design of viscoelastically supported bridges, this paper investigates the analytical solutions of train-induced vibrations in railway bridges with low-stiffness and high-damping rubber bearings. First, the shape function of the viscoelastic bearing reinforced concrete (RC) beam is derived for the dynamic response of the viscoelastic bearing RC beam subjected to a single moving load. Furthermore, based on the simplified shape function, the dynamic response of the viscoelastic bearing RC beam under equidistant moving loads is studied. The results show that the stiffness and damping effect on the dynamic response of the supports cannot be neglected. The support stiffness might adversely increase the dynamic response. Further, due to the effect of support damping, the free vibration response of RC beams in resonance may be significantly suppressed. Finally, when the moving loads leave the bridge, the displacement amplitude of the viscoelastic support beam in free vibration is significantly larger than that of the rigid support beam.
为了给消除共振和优化粘弹性支承桥梁的设计提供理论依据,本文研究了采用低刚度高阻尼橡胶支座的铁路桥梁中列车引起振动的解析解。首先,针对粘弹性支座钢筋混凝土(RC)梁在单个移动荷载作用下的动力响应,推导了粘弹性支座的形状函数。此外,基于简化的形状函数,研究了粘弹性支座RC梁在等距移动荷载作用下的动力响应。结果表明,支座刚度和阻尼对动力响应的影响不可忽略。支座刚度可能会不利地增加动力响应。此外,由于支座阻尼的作用,RC梁在共振时的自由振动响应可能会得到显著抑制。最后,当移动荷载离开桥梁时,粘弹性支承梁在自由振动中的位移幅值明显大于刚性支承梁的位移幅值。