Abstract: By performing laboratorial shield tunneling simulation tests, the effect of shield tunneling on the deformation of underground pipelines is studied under the condition of three kinds of relative positions between tunnel and pipelines, namely vertical, heterotropic, and parallel. With ongoing construction of subway in Hefei region as engineering background, the laws of settlement, deformation, and relative angle of the underground pipelines are mainly researched. Results show that the second disturbance is more likely to induce settlement in soil, which exerts a greater influence on the displacement of underground pipelines. The range where the pipeline deforms along the tunnel axial direction is found to be different from that along the tunnel radial direction during shield tunneling, showing a greater induced deformation of underground pipeline along the radial direction than that along the tunnel axial direction. After the tunnel excavation, the earth pressure under the pipelines change, and an area of load free appears below the middle section of the pipeline, which gradually reduces the earth pressure while increases the additional stress under the two marginal sections of the pipeline. The conclusions can provide a reference of damage controlling for the prediction of the effect of shield tunneling on the underground pipelines.

Key words: simulation test, shield tunneling, underground pipelines, deformation, relative angle