| Maglev train is a new type of ground tracked transport, which has favorable developmental foreground. But the environment vibration induced by maglev train has not been paid enough attention. Except for a little of field test study, theoretical study and numerical analysis on ground vibration induced by maglev train has not been reported at present. Based on this research background, this paper establishes numerical models of ground vibration induced by maglev train, which mainly aims to the high-speed Shanghai maglev transport system and the low-speed Qingcheng Mountain maglev transport system. Then numerical simulations of ground vibration are carries out using the ANSYS and SIMPACK software.Based on the previous maglev vehicle-guideway interaction model, the maglev vehicle-guideway-pier system model is established by the ANSYS and SIMPACK software, which considers the flexible piers in detail. The maglev vehicle-guideway-pier system model is verified by some comparison analyses, and is used to obtain dynamic electromagnetic forces. Furthermore, the finite element models of ground foundation according to the Shanghai high-speed maglev transport system and the Qingcheng Mountain low-speed maglev transport system. In the models, soil foundation is meshed with the three dimensional finite element. The scattering characteristics of the calculation domain edges are simulated through the visco-elastic artificial boundary. Then the numerical model of ground vibration is established.The ground vibration responses produced by the high/low-speed maglev trains are calculated and compared to the previous test results. The calculated results of the vibration resources are accordance with the field test, which shows that the numerical model of ground vibration is reasonable. Comparing to the calculated results of ground vibration responses induced by urban transit, it is founded that the ground vibration characteristics of both ground transport system are similar, but the ground vibration level induced by maglev train is much smaller. For the high speed maglev system, when the running speed is 172km/h, the vibration level of the observation point with 26m distance from route centre meet approximately the daytime limit 70dB of the residential area specified by the Chinese standard GB10070—1988, and is less than the daytime limit 75dB and nighttime limit 72dB of the mingle area,the business centre area,industry concentration area and both side of railway line. For the low speed maglev system, when the running speed is 80km/h, the ground vibration level of the observation point with 20m distance from route centre is less than the various nighttime limit of all the urban area. The related study results in this paper are useful for the plan and design of maglev line in urban area. |
