为评估盾构隧道预制中隔墙在列车振动荷载和气动荷载作用下的安全性，从模态分析和振动响应分析2个方面开展研究。首先，基于流体力学计算软件采用数值模拟方法研究列车单车行驶和双车交会对预制中隔墙隧道气动效应的影响，得到预制中隔墙的气动荷载时程曲线；然后，采用动力有限元法分析列车振动荷载和气动荷载条件下预制中隔墙的模态振型及振动响应。结果表明： 1）列车以160 km/h单车行驶时，隧道内各测点压力变化一致，最大压力出现在距入口1/3隧道长度处；双车交会时，中隔墙两侧压力幅值变化不一致，导致压力变化曲线不同。2）随着埋深增加，中隔墙的弯曲模态频率略有下降，且垂向位移响应显著强于水平位移响应；预制中隔墙弯曲模态频率1阶弯曲模态对应的频率为16.106 6~17.141 9 Hz，现场测试的隧道壁面主频范围为0~2 Hz，预制中隔墙在固定约束条件下无共振风险。3）中隔墙振动效应主要受列车振动荷载影响，受气动荷载影响较小。
The modal analysis and
vibration response of prefabricated middle partition walls in large-diameter shield tunnels under train vibration load and aerodynamic
load are investigated. Numerical simulation methods based on fluid mechanics
calculation software are used to systematically examine the influence of single-vehicle travel and double-vehicle
intersection on the aerodynamic effects of the middle partition wall, obtaining
aerodynamic load time-history curves. In addition, the
dynamic finite element method is utilized to analyze the modal vibration mode
and vibration response of the prefabricated middle partition walls. The results
reveal the following: (1) When a single train travels at a speed of 160 km/h,
the pressure changes at each measuring point in the tunnel are consistent, with
the maximum pressure occurring at the monitoring point of 1/3 tunnel length
from entrance. When two trains intersect, the pressure amplitude on both sides
of the partition wall changes inconsistently, leading to differences in the
pressure curves. (2) As the burial depth of the tunnel increases, the bending
modal frequency of the middle partition wall slightly decreases, and the
vertical displacement response is significantly stronger than the horizontal
displacement response. The frequency corresponding to the first-order bending mode of the prefabricated middle partition wall ranges
between 16.106 6 and 17.141 9 Hz, differing from the main frequency range of 0－2 Hz observed in the tunnel wall during on-site
testing. This indicates that the prefabricated middle partition wall poses no
resonance risk under fixed constraint. (3) The vibration effect of the middle
partition wall is primarily influenced by the train load, whereas the
aerodynamic load has a relatively minor impact on the vibration response.
