城际铁路双轨道列车盾构隧道振动响应分析

针对首例城际铁路双轨道大直径盾构隧道(外径12.4 m、管片衬砌厚0.55 m)下穿南水北调中线总干渠工程实例,建立有限元数值分析模型,分析了列车行驶振动荷载对隧道衬砌结构和渠底的振动响应规律.采用激振力函数综合考虑行车平稳性、动力附加轮毂和波形磨耗等因素模拟列车振动荷载,变换轨道不平顺值由0.40 mm增至1.00 mm,列车运行工况按单列车单向行驶和双列车对向行驶,列车设计时速200 km/h.研究表明:双列车对向行驶对隧道衬砌混凝土应力和渠底面位移的影响较大,轨道不平顺值对隧道衬砌混凝土应力影响较大,但对渠底面位移影响很小.研究成果为盾构隧道和南水北调中线总干渠安全运营和维护管理的决策提供了研究依据.

Vibration Response Analysis of Large Diameter Shield Tunnel for Intercity Railway with Two-orbit Trains

As the first case of the shield tunnel for intercity railway with two-orbit trains, 12.4 m outer-diameter and 0.55 m thick segmental lining running down through the main channel of the middle route of South-to-North Water Diversion Project, the vibration responses of the lining structure of shield tunnel and the bottom surface of main channel are analyzed with finite-element method. The excitation force function is used to simulate the train vibration loads by considering the factors such as driving stability, power additional hub and waveform wear comprehensively. The value of orbital irregularity is changed from 0.40 mm to 1.00 mm. And the operating conditions of the trains were single train with one-way or double trains in opposite directions with 200 km/h design speed. The results indicated that there is a bigger effect on the concrete circumferential stress of tunnel lining and the displacement of channel bottom with running double trains, compared with single train. The rail irregularity value has great influence on the concrete circumferential stress of tunnel lining and little influence on the displacement of channel bottom. And it will provide a reference for the decision on safe operation, maintenance and management of shield tunnel and main channel of the middle route of South-to-North Water Diversion Project.