Reasons and laws of ground vibration amplification induced by vertical dynamic load
来源期刊：中南大学学报(英文版)2014年第4期
论文作者：MA Meng(马蒙) LIU Wei-ning(刘维宁) 孙宁 王文斌
文章页码：1660 - 1671
Key words：railway traffic; vibration amplification zone; drop-weight test; ground vibration; fluctuant attenuation
Abstract: The phenomenon of ground vibration amplification caused by railway traffic was found and proved. In order to study the reasons which cause the amplification, a drop-weight test was performed. Then, the model for both homogeneous and layered soil subjected to a harmonic vertical load was built. With the help of this model, displacement Green’s function was calculated and the propagation laws of ground vibration responses were discussed. Results show that: 1) When applying a harmonic load on the half-space surface, the amplitude of ground vibrations attenuate with fluctuation, which is caused by the superposition of bulk and Rayleigh waves. 2) Vibration amplification can be enlarged under the conditions of embedded source and the soil layers. 3) In practice, the fluctuant attenuation should be paid attention to especially for the vibration receivers who are sensitive to single low frequencies (<10 Hz). Moreover, for the case of embedded loads, it should also be paid attention to that the receivers are located at the place where the horizontal distance is similar to embedded depth, usually 10 to 30 m for metro lines.
MA Meng(马蒙)1, 2, LIU Wei-ning(刘维宁)2, SUN Ning(孙宁)3, WANG Wen-bin(王文斌)3
(1. State Key Laboratory of Track Technology of High-Speed Railway (China Academy of Railway Sciences),
Beijing 100081, China;
2. School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, China;
3. Beijing Engineering Consultation Co., Ltd of China Academy of Railway Sciences, Beijing 100081, China)
Abstract:The phenomenon of ground vibration amplification caused by railway traffic was found and proved. In order to study the reasons which cause the amplification, a drop-weight test was performed. Then, the model for both homogeneous and layered soil subjected to a harmonic vertical load was built. With the help of this model, displacement Green’s function was calculated and the propagation laws of ground vibration responses were discussed. Results show that: 1) When applying a harmonic load on the half-space surface, the amplitude of ground vibrations attenuate with fluctuation, which is caused by the superposition of bulk and Rayleigh waves. 2) Vibration amplification can be enlarged under the conditions of embedded source and the soil layers. 3) In practice, the fluctuant attenuation should be paid attention to especially for the vibration receivers who are sensitive to single low frequencies (<10 Hz). Moreover, for the case of embedded loads, it should also be paid attention to that the receivers are located at the place where the horizontal distance is similar to embedded depth, usually 10 to 30 m for metro lines.
Key words:railway traffic; vibration amplification zone; drop-weight test; ground vibration; fluctuant attenuation
