地铁盾构隧道引起邻近燃气管线变形规律研究

STUDY ON DEFORMATION LAW OF ADJACENT GAS PIPELINE CAUSED BY SHIELD TUNNEL IN METRO

为探究地铁盾构隧道引起邻近燃气管线变形规律,以济南某城市交通区间盾构隧道为工程背景,分析管线沉降变形的5个阶段以及盾构施工引起管线沉降的主要因素,并基于Peck经验公式对盾构施工引起燃气管道周边地层移动情况进行理论计算,预测管道本身变形与三维有限元数值模型结果结合,共同揭示地铁盾构隧道引起邻近燃气管线变形规律。研究表明:盾构施工对燃气管线的影响因素主要为盾构掌子面平衡压力和盾尾注浆压力;引用Peck经验公式对盾构施工引起燃气管道周边地层移动情况理论计算结果为2.5~10.2mm,可预测管线变形较小;在掌子面平衡压力150kPa、注浆压力300kPa情况下,发现燃气管道最大竖向沉降值出现在盾构工作面推过后13.5m位置。

To explore the subway shield tunnel deformation law caused by adjacent gas pipeline,and in Ji'nan city traffic interval shield tunnel as the engineering background,analysis of five stages of settlement of pipeline and the main factors of pipeline settlement caused by shield construction,and based on Peck empirical formula to gas pipeline caused by shield construction surrounding strata mobile computing theory,combined with the results of 3D finite element numerical model,the deformation law of adjacent gas pipeline caused by subway shield tunnel is revealed.The results show that the main influencing factors of shield construction on gas pipeline are balance pressure of shield face and grouting pressure of shield tail.Using Peck empirical formula,the theoretical calculation results of strata movement around gas pipeline caused by shield construction are 2.5~10.2 mm,which can predict the pipeline deformation is small.In the case of balance pressure 150 kPa and grouting pressure 300 kPa,it is found that the maximum vertical settlement value of the gas pipeline is 13.5 m after the shield working face is pushed.