飞机动荷载下明挖隧道动力响应研究

Study on Dynamic Response of Open-cut Tunnel under Aircraft Dynamic Load

随着国内外城市轨道交通迅速发展,部分地铁区间隧道不得不下穿机场滑行道,文章依托新建成都天府国际机场工程,采用三维数值模拟研究,对飞机滑行动荷载下明挖隧道基坑回填沉降及隧道结构的受力进行研究分析,得出以下结论:(1)当飞机滑行到最大基坑回填高度处,路面最大沉降为3.965cm,此时下方隧道结构拱顶沉降为2.134 cm,均满足沉降控制要求;(2)飞机滑行道下明挖隧道群在飞机动荷载作用下结构应力有较大差异。当飞机作用在隧道上方附近时,隧道最大主应力在拱底处约为3.64 MPa,满足隧道结构安全系数设计要求。相关研究成果可为类似工程施工提供参考。

With the rapid development of urban rail transit at home and abroad,some subway tunnels have to go down the airport taxiway.Relying on the newly built Tianfu International Airport project,using three-dimensional numerical simulation,the open pit backfills settlement and tunnel structural stress under aircraft taxiing action load were studied and analyzed.The following conclusions are drawn:(1)When the aircraft glides to the position with maximum backfill height of the foundation pit,the maximum settlement of the pavement is 3.965 cm,and the settlement of the lower tunnel structure is 2.134 cm,which meet the settlement control requirements.(2)The structural stress of the open-cut tunnel group under the aircraft taxiway is greatly different under the dynamic load of the aircraft.When the aircraft acts near the upper part of the tunnel,the maximum principal stress of the tunnel is about 3.64 MPa at the bottom of the arch,which meets the design requirements of the safety factor of the tunnel structure.Relevant research results can provide reference for similar engineering construction.