摘要
为探索复合地层中双线盾构隧道施工诱发的地表沉降规律,首先基于地表沉降监控量测数据验证数值模型的合理性,再基于数值模拟方法,从地层复合比、隧道覆径比和隧道间径比3个角度进行分析,研究表明:(1)总沉降槽宽度、单侧沉降槽宽度、地表沉降及最大地表沉降差异率均随地层复合比的增大而增大,随覆径比的增大而减小,且差异明显;(2)间径比是影响地表沉降曲线的重要因素,当间径比为1.0时,地表沉降曲线为单峰形,最大地表沉降发生在隧道中线位置,为19.2 mm;当间径比为2.0时,地表沉降曲线变化为双峰形且不随间径比的增大而变化,最大地表沉降发生在隧道中心线位置,左、右线隧道中心线位置处的地表沉降分别为13.5 mm、11.6 mm;当间径比为5.0时,左右线隧道的地表沉降曲线趋于相互独立。
In this paper,the surface subsidence law induced by the construction of the double-line shield tunnel was presented with numerical Simulation.Firstly,according to the monitoring data of surface subsidence,the rationality of the numerical model was verified,subsequently,effects of the compound ratio of ground(abbreviated asα),the ratio between thickness of covering ground and tunnel diameter(abbreviated asβ),the ratio between spacing distances and tunnel diameter(abbreviated asγ)on surface subsidence law were presented.Results show that:(1)The unilateral width of subsidence tank,surface subsidence,difference rate of maximum surface settlement of left-line tunnel and right-line tunnel increases asαincreases,but decreases asβincreases.With the increase ofαand the decrease ofβ,the difference is obvious.(2)γis an important factor affecting surface subsidence curve,γ=1.0,surface subsidence curve is single peak shape,maximum surface subsidence is 19.2 mm,occurring at the centerline of the tunnels,γ=2.0,surface subsidence curve is double peak shape and does not change with the increase ofγ,maximum surface subsidence occurs at the centerline of the tunnel,surface subsidence of the centerline of left-line tunnel is 13.5 mm,surface subsidence of the centerline of right-line tunnel is 11.6 mm,γ=5.0,surface subsidence curve of left-line tunnel and right-line tunnel tend to be independent of each other.
作者
郭朝
Guo Chao(China Railway Design Corporation,Tianjin 300308,China)
出处
《铁道勘察》
2021年第4期58-62,共5页
Railway Investigation and Surveying
关键词
复合地层
双线盾构隧道
地表沉降
数值模拟
compound ground
double-line shield tunneling
surface subsidence
numerical simulation
