摘要
现有钻孔隧道力学分析模型主要集中在中、深度隧道(覆盖层直径比C/D≥2),但这类隧道模型因忽略了浮力且没有考虑到隧道衬砌的实际荷载,并不适用于浅埋钻孔隧道的力学分析。此文结合浅埋隧道的有限元分析,提出了一种浅层隧道计算模型,并研究了隧道截面最优厚度直径比d/D与覆盖层直径比C/D之间的关系。该模型中的隧道衬砌荷载包括浅层隧道顶部和底部的荷载差,利用提出的浅层隧道模型计算隧道截面上特定点处的土压力,以及结合有限元法进行结构分析得出一系列关键结论。结果表明,在有浮力的浅埋隧道分析中,隧道衬砌归一化内力和变形较无浮力的浅埋隧道显著大,当改变隧道覆盖深度时,隧道衬砌的最大变形值达到最小。结合结构分析和隆起分析的结果给出了掘进过程中隧道某断面C/D值的最优断面直径比值和最优覆盖层直径C/D比值。
Existing research on the structural design of bored tunnels was mainly focused on the medium and deep tunnels(the ratio of overburden diameter). However, it is not suitable for shallow tunnels because it ignores the buoyancy and does not consider the actual load of tunnel lining. Based on the finite element analysis(FEA) of shallow tunnel, this paper presents a calculation model of shallow tunnel. The relationships between the optimal thickness diameter ratio of tunnel section and the diameter ratio of overburden are studied. The tunnel lining load in this model does not include the load difference between the top and the bottom of the shallow tunnel. Some conclusions are obtained through the calculation of the earth pressure at the specific point on the tunnel section, and the combination of the finite element method for structural analysis. The structural analysis of the proposed shallow tunnel model shows that the normalized internal force and deformation of the tunnel lining increase significantly in the design of the shallow tunnel without and with buoyancy. It can be seen from the analysis results that the maximum deformation of the tunnel lining reaches the minimum when the tunnel cover depth is adjusted. By combining structural and uplift analysis, the optimal section diameter ratio and the optimal overburden diameter ratio C/D for a specific face value can be obtained.
作者
赵立财
ZHAO Licai(Department of Civil and Construction Engineering,National Taiwan University of Science and Technology,Taipei 10607,China;China Railway 19th Bureau Group Third Engineering Co.,Ltd.,Shenyang 110136,China)
出处
《防灾减灾工程学报》
CSCD
北大核心
2023年第1期88-96,共9页
Journal of Disaster Prevention and Mitigation Engineering
基金
辽宁省“兴辽英才计划”青年拔尖人才资助项目(XLYC2007146)
中铁十九局集团有限公司科技研究开发计划项目(2021-B03)资助。
关键词
覆盖层直径比
隧道衬砌
浅埋钻孔隧道
砂岩
cover-to-diameter ratio
tunnel lining
shallow bored tunnel
sandstone
