摘要
近年来,地铁列车运行引起的周围环境的振动是热门课题,但是列车荷载移动下的动力响应问题十分复杂。在案例中,应尽可能地贴近实际工程,迅速、精确地计算预测地基与地铁隧道的振动变形。本文把2.5维有限元法从理论研究运用到宁波轨道交通三号线类矩形隧道振动分析中,建立了2.5维实际轨道模型的有限元模型,并赋以实际动力学参数,分析了在类矩形地铁运行荷载下,地基及其轨道的振动受地铁隧道的埋设深度、地铁行车速度、地基土层性质等重要因素的影响。列车行驶时,地表的振动强度随着隧道的埋深的减小而增大,振动强度在x=0时达到最大;在不同的土体剪切波速下,振动衰减情况趋于一致,在x=0的情况下振动强度最大;列车运行时引起的振动强度随着列车行驶速度的增加而增大,且在x=0时,其引起的振动强度的差值达到最大。地表振动的强度随隧道埋深变浅、列车运行速度增大、土体剪切波速减小而增大,且远场区域内的振动水平已经衰减到安全水平,只需在地铁线路附近区域内采取一定的地面减振控制措施。
In recent years,the vibration of the surrounding environment caused by the operation of subway trains is a hot topic,but the dynamic response problem under the movement of train loads is very complicated.In the case,it should be as close as possible to the actual project,and the vibration deformation of the foundation and subway tunnel should be calculated and predicted quickly and accurately.Applying the 2.5-dimensional finite element method from theoretical research to the vibration analysis of the quasi-rectangular tunnel of Ningbo Rail Transit Line 3,the finite element model of the 2.5-dimensional actual track model is established,and the actual dynamic parameters are assigned to analyze the quasi-rectangular subway.Under the operating load,the vibration of the foundation and its track is affected by important factors such as the buried depth of the subway tunnel,the speed of the subway,and the properties of the foundation soil layer.The results show that:when the train is running,the vibration intensity of the ground surface increases with the decrease of the buried depth of the tunnel,and the vibration intensity reaches the maximum when x=O;the vibration attenuation tends to be consistent under different soil shear wave velocities,the vibration intensity is the largest when x=O;the vibration intensity caused by the train increases with the increase of the speed of the train,and when x=O,the difference of the vibration intensity caused by it reaches the maximum.The intensity of surface vibration increases as the tunnel burial depth becomes shallower,the train running speed increases,and the soil shear wave velocity decreases,and the vibration level in the far-field area has been attenuated to a safe level.Take certain ground vibration control measures.
作者
周奇辉
张琼方
丁智
孙苗苗
黄鑫
林若涵
Zhou Qihui;Zhang Qiongfang;Ding Zhi;Sun Miaomiao;Huang Xin;Lin Ruohan(Power China Huadong Engineering Corporation,Hangzhou 311122,China;Department of Civil Engineering,Zhejiang University City College,Hangzhou 310015,China;Department of Civil Engineering,Zhejiang University,Hangzhou 310058,China;Key Laboratory for Safe Construction and Intelligent Maintenance of Shield Tunnels in Key Cities of Zhejiang Province,Hangzhou 310015,China)
出处
《科技通报》
2023年第11期103-109,共7页
Bulletin of Science and Technology
基金
浙江省重点研发计划项目(2020C01102)
浙江省自然科学基金项目(LTGG23E080002)。
关键词
地铁运营
动力响应
类矩形隧道
振动荷载
subway operation
dynamic response
rectangular-like tunnel
vibration load
