摘要
In this paper, the vibration influence on a monument caused by Chengdu Subway Line 2 is analyzed. Due to its elaborate and unique design, both structural and architectural damages should be avoided. First, the allowable root mean square （RMS） velocity at the foundation of the monument is derived and a site measurement is performed to obtain the background vibrations induced by road traffic. In addition, a train-track coupled model and 3D tunnel-soil-structure coupled finite element models are built to predict the dynamic response of the monument. Prediction models are checked by site measurement in Beijing Subway Line 5. Different kinds of fasteners and train speeds are compared and discussed as well. Results show that： （1） At a train speed of 72 km/h, all the traffic vibrations exceed the low limit no matter what kind of fastener is used, which is mainly due to the contribution of road traffic. Slowing down train speeds can cause effective vibration attenuation; （2） Vibrations drop dramatically with the train speed from 65 to 58 km/h. When the train speed is lower than 58 krn/h, vibrations are lower than allowable value even if the contribution of road traffic is considered.
In this paper, the vibration influence on a monument caused by Chengdu Subway Line 2 is analyzed. Due to its elaborate and unique design, both structural and architectural damages should be avoided. First, the allowable root mean square (RMS) velocity at the foundation of the monument is derived and a site measurement is performed to obtain the background vibrations induced by road traffic. In addition, a train-track coupled model and 3D tunnel-soil-structure coupled finite element models are built to predict the dynamic response of the monument. Prediction models are checked by site measurement in Beijing Subway Line 5. Different kinds of fasteners and train speeds are compared and discussed as well. Results show that: (1) At a train speed of 72 km/h, all the traffic vibrations exceed the low limit no matter what kind of fastener is used, which is mainly due to the contribution of road traffic. Slowing down train speeds can cause effective vibration attenuation; (2) Vibrations drop dramatically with the train speed from 65 to 58 km/h. When the train speed is lower than 58 km/h, vibrations are lower than allowable value even if the contribution of road traffic is considered.
基金
Project supported by the National Natural Science Foundation of China (No. 51008017)
the Fundamental Research Funds for the Central Universities (Nos. 2009JBM074 and 2009JBM075), China
