超浅埋隧道下穿高速路基沉降控制标准与技术研究  

Research on Settlement Control Standard and Technology of Ultra-shallow Buried Tunnel Under High-speed Subgrade

作　　者：陈志敏[1,2] 周飞 文勇 黄林祥 任益 CHEN Zhimin;ZHOU Fei;WEN Yong;HUANG Linxiang;REN Yi(College of Civil Engineering,Lanzhou Jiaotong University,Lanzhou,Gansu 730070,China;National And Local Joint Engineering Laboratory,Lanzhou Jiaotong University,Lanzhou,Gansu 730070,China;China Railway 18th Bureau Group Co.,Ltd.,Tianjin 300222,China;Chongqing Railway(Group)Co.,Ltd.,Chongqing 401120,China)

机构地区：[1]兰州交通大学土木工程学院,甘肃兰州730070 [2]兰州交通大学道桥工程灾害防治技术国家地方联合工程实验室,甘肃兰州730070 [3]中铁十八局集团有限公司,天津300222 [4]重庆市铁路(集团)有限公司,重庆401120

出　　处：《公路工程》2022年第4期61-69,116,共10页Highway Engineering

基　　金：国家自然科学基金项目(11662007);甘肃省建设科技攻关项目(JK2018-33)。

摘　　要：新鼓山隧道下穿高速公路段上覆土最小厚度仅4.1 m,要保证公路运营不受隧道施工影响非常困难。通过3种计算方法对比分析,确定路基的沉降基准值、预警值和报警值分别为36、21.6、28.8 mm。建立新鼓山隧道下穿高速公路三维有限元计算模型,研究在不同开挖方法、不同进尺和不同支护方案下隧道开挖引起路基沉降的控制效果。结果表明,在浅埋隧道施工中宜选择开挖方法为双侧壁导坑法,开挖进尺为0.5 m,预加固措施采取双层大管棚的效果最佳,通过以上措施可以将路基沉降控制在36 mm以内,确保隧道施工的安全性与高速公路的正常运营。The minimum thickness of the overburden soil of the New Gushan Tunnel under the expressway section is only 4.1 m,so it is very difficult to ensure the highway operation is not affected by the tunnel construction.Through the comparative analysis of 3 calculation methods,the settlement base value,early warning value and alarm value of the subgrade are determined to be 36,21.6 and 28.8 mm respectively.The three-dimensional finite element calculation model of the New Gushan Tunnel under the expressway is established to study the control effect of subgrade settlement caused by tunnel excavation under different excavation methods,different footage and different support schemes.The results show that in the construction of shallow buried tunnels,the excavation method should be double-wall pit guide method,the excavation progress should be 0.5 m,and the pre-reinforcement measures should be double-layer large pipe canopy with the best effect.Through the above measures,the subgrade settlement can be controlled within 36 mm to ensure the safety of tunnel construction and the normal operation of expressway.

关 键 词：超浅埋隧道 路基沉降 控制标准 开挖进尺 开挖方法 超前支护 

分 类 号：U455.4[建筑科学—桥梁与隧道工程]