Attenuation and propagation characteristics of railway load-induced vibration in a loess area

Abstract

The long-term vibration caused by the operation of high-speed trains not only reduces the strength and stability of a roadbed but also affects infrastructure such as buildings along the line, resulting in a series of engineering–environmental problems. In this study, field tests were conducted to examine the ground vibrations caused by the operation of the Datong-Xi’an high-speed railway; three different line forms––viaducts, embankments, and embankment culverts––were considered. First, the propagation law and attenuation characteristics of environmental vibration caused by high-speed railways in typical loess areas were analyzed using time-domain and frequency-domain features. Second, based on the Bornitz model and combined with the measured data, the geometric attenuation coefficient and damping attenuation coefficient of the formula are discussed, and the optimized Bornitz model is used to predict the ground vibration caused by high-speed trains in a loess area. The results showed the following: (1) The ground vibration caused by high-speed train operation is a periodic excitation, and there is an obvious superimposition effect at the bogie of the train. The vertical vibration acceleration of the ground surface decays continuously as the distance from the vibration source increases. The dominant frequency also decreased with an increase in distance. (2) The geometric attenuation coefficient of the bridge and embankment sections decrease with an increase in the distance from the vibration source, and the overall attenuation is a power function. Different distances should be regarded as different types of vibration sources, and the damping attenuation coefficient differs at different measurement points. (3) The improved Bornitz model was used to predict ground vibrations caused by the operation of high-speed trains. A comparison with the measured data showed good agreement, explaining the amplification effect in the attenuation of ground vibration.