摘要
建立隧道上浮至土体边界顶部的隧道开挖断面收敛模型,基于随机介质理论,推导地面出入式盾构隧道施工仅考虑土体损失引起的土体沉降计算方法,采用Winkler地基模型,简化地下管线的受力模型,得到地面出入式盾构法隧道,浅覆土段施工引起的垂直交叉地下管线变形、弯矩、应力和应变的计算公式。考虑盾构掘进时上仰α角以及浅覆土效应,通过算例分析,探讨了盾构掘进时上仰α角、管线埋深以及管线直径改变对地下管线受力和变形的影响。研究结果表明,随着α的增大,盾构开挖面后方的管线变形和弯矩曲线趋势呈逐渐减小;α角和管径改变只对管线横向最大正负弯矩以及最大沉降、隆起附近影响较大;管线埋深改变时,由于隧道上浮,位于隧道顶部附近土体沉降值变小,当埋深位置较深且靠近隧道顶部时,管线的弯矩和变形反而变小。
Acoording to the tunnel excavation section convergence model of the tunnel up to the top of the soil boundary based on the stochastic medium theory, we deduced the calculation formula of soil settlement caused by soil loss during construction of the ground-entry shield tunnel, and simplified it based on the Winkler foundation model. The force model of underground pipelines deduces the calculation formulas of vertical cross-underground pipeline deformation, bending moments, stress and strain caused by the construction of shallow overburden tunnels. Considering the α angle and the shallow overburden effect during shield tunneling, the influence of α angle, pipe depth, and pipeline diameter change on the stress and deformation of underground pipeline during shield excavation is discussed through numerical examples. The results show that with the increase of α, the trend of pipe deformation and bending moment curve behind the excavation surface of the shield gradually decreases; α angle and pipe diameter change only for the maximum and negative bending moments of the pipeline and the parts of maximum settlement and uplift. The impact is large; when the buried depth of the pipeline changes, the settlement value of the soil near the top of the tunnel becomes smaller due to the floating of the tunnel. When the depth of the buried depth is deeper and close to the top of the tunnel, the bending moment and deformation of the pipeline become smaller.
作者
黄文
魏纲
HUANG Wen;WEI Gang(Department of Civil Engineering,Zhejiang University City College,Hangzhou 310015,China)
出处
《低温建筑技术》
2018年第11期83-88,共6页
Low Temperature Architecture Technology
基金
浙江省科技厅公益技术应用研究项目(2016C33051)
关键词
地面出入式盾构法
地下管线
浅覆土
弯矩
变形
ground penetrating shield tunnelling method
buried pipeline
shallow soil
bending moment
deformation
