Pasternak地基中盾构隧道穿越引起地下管线竖向位移

摘要

采用统一土体移动模型三维解计算盾构施工引起的地下管线平面处土体竖向位移,并基于Pasternak地基模型对地下管线受力模型进行简化,建立单线、双线盾构隧道开挖引起的地下管线三维竖向位移计算公式.将计算结果与实测值进行对比;并探讨了管线材质、管线埋深以及土体损失率改变对管线竖向位移的影响.研究结果表明:计算结果与实测值比较吻合,可以计算单线和双线盾构开挖工况;双线隧道开挖引起的管线竖向位移大于单线隧道引起的管线竖向位移;管线材质和管线埋深的改变对管线最大竖向位移的影响较小,管线最大竖向位移随抗弯刚度增大而减小,随埋深增大而增大;土体损失率的改变对管线最大竖向位移的影响较大,土体损失率越大管线最大竖向位移也越大.%By using the three dimensional solution of uniform ground movement pattern to calculate the soil vertical displacement in the plane of underground pipeline caused by shield construction,simplifying the mechanical model of underground pipeline based on Pasternak foundation model,the three-dimensional calculation formula of vertical displacement of underground pipeline caused by single and double shield tunnel excavation is established.By comparing the calculated results with the measured values,the influence to the vertical displacement of pipeline is discussed of changing in pipeline material,buried depth of pipeline and soil loss rate.The result indicates that the calculated value almost coincides with measured value,which can be used to calculate the working conditions of single and double shield tunneling;The vertical displacement of the pipeline caused by double tunnel excavation is larger than the vertical displacement caused by the single line tunnel;The change of pipeline material and the buried depth of pipeline have little effect on the maximum vertical displacement of pipeline,The maximum vertical displacement of pipeline decreases with the increase of pipe bending stiffness,and increases with the increase of buried depth of pipeline;The change of soil loss rate has a great influence on the maximum vertical displacement of pipeline,and the maximum vertical displacement increases with the increase of soil loss rate.