Vibration Characteristics of Prefabricated Ballastless Tracks for Metro Lines Crossing beneath Ancient Buildings
With the rapid development of urban rail transit,environmental vibration is becoming a growing problem.Especially for ancient building protected sections,vibration inevitably affects ancient buildings.At present,there is still a lack of research on the impact of rapid urban rail transit on ancient buildings.Based on the coupled dynamics model,this paper compares and analyses the vibration characteristics of general track beds and high-grade vibration reduction track beds in ancient building sections.The results show that:(1)The high-grade vibration reduction track beds effectively reduce the vibration of ancient buildings,with vertical vibration speed reduced by 28％and lateral vibration speed reduced by 32.3％;(2)The vibration reduction effect of high-grade vibration reduction track beds on tunnel walls can reach 11.29 dB,and that of soil mass can reach 10.78 dB;(3)The place 10～20 m away from the vibration source in horizontal direction is considered an unfavorable vibration zone,and sensitive areas shall be avoided here;(4)The train speed has a great influence on the vibration of ancient buildings.When the train speed is reduced to 80 km/h,the vibration velocity of ancient buildings decreases greatly with the best vibration reduction effect.
metro linesancient building sectionvibration reductionprefabricatedballastless trackvibration characteristics
NETL
NSTL
万方数据
