不同地震波对浅埋隧道下穿桥梁的影响  

Influence of Different Seismic Waves on Shallow Buried Tunnel Underpass Bridges

作　　者：冯志文 晏长根[2] FENG Zhiwen;YAN Changgen(Direct subsidiary of Shanxi Chengda Highway Survey and Design Co.,Ltd,Taiyuan Shanxi 030006,China;School of Highway,Chang’an University,Xi’an Shaanxi 710054,China)

机构地区：[1]山西诚达公路勘察设计有限公司直属公司,山西太原030006 [2]长安大学公路学院,陕西西安710054

出　　处：《安徽理工大学学报（自然科学版）》2024年第4期60-67,共8页Journal of Anhui University of Science and Technology:Natural Science

基　　金：国家自然科学基金资助项目(42077265)。

摘　　要：目的为了深入分析不同超越概率地震波作用下新建浅埋隧道下穿高铁桥墩的对桥墩及其桩基的影响。方法以实际项目为依托,利用数值模拟手段分析研究了隧道下穿过程对既有高铁桥墩的影响以及当遭遇50年不同超越概率的地震加速度时隧道下穿桥墩前后各结构的力学响应。结果浅埋黄土隧道下穿桥墩施工过程中桥墩前后的1.5倍隧道埋深范围内墩顶的变形最大,在50年超越概率为10%和50年超越概率为2%的地震作用下隧道开挖后墩顶的位移是隧道未开挖墩顶位移的2~4倍,隧道的开挖一定程度上可以减轻桩基的震害,地震作用下隧道衬砌受力的最大位置为拱脚处,同时在一定深度范围内隧道开挖会增强土体的加速度放大效应。结论在遭遇50年超越概率为10%和2%的地震波时,隧道的建设与否对于桥墩的形变影响十分明显,对实际工程建设过程中具有一定的指导意义。Objective In order to deeply analyze the impact of newly built shallow buried tunnels crossing high-speed railway bridge piers and their pile foundations under the action of seismic waves with different exceedance probabilities.Methods Based on the actual projects,numerical simulation methods were used to analyze and study the impact of tunnel underpass process on the existing high-speed railway bridge piers,as well as the mechanical response of various structures before and after tunnel underpass bridge piers when encountering seismic accelerations with different exceedance probabilities for 50 years.Results The results showed that during the construction process of shallow buried loess tunnel crossing bridge piers,the deformation of the pier top was the largest within the range of 1.5 times the depth of the tunnel before and after the bridge piers.Under the earthquake action with a 50 year exceedance probability of 10%and a 50 year exceedance probability of 2%,the displacement of the pier top after tunnel excavation was 2~4 times that of the pier top before the tunnel was excavated.The excavation of the tunnel would,to some extent,reduce the seismic damage of the pile foundation.The maximum stress on the tunnel lining under earthquake action was at the arch foot.At the same time,tunnel excavation within a certain depth range would enhance the acceleration amplification effect of the soil.Conclusion When encountering seismic waves with a probability of exceeding 10%and 2%in 50 years,the construction of tunnels has a significant impact on the deformation of bridge piers,which has certain guiding significance for the actual engineering construction process.

关 键 词：岩土工程 隧道下穿桥梁 地震加速度 墩顶变形 数值模拟 加速度放大系数 

分 类 号：U416.1[交通运输工程—道路与铁道工程]