隧道盾构施工对邻近管线群位移影响的模型试验研究

隧道盾构施工会对邻近管线造成不利影响,但目前对管线位移的研究多集中在单一管线方面,考虑管线之间影响的研究较少。针对这一问题,开展砂土地层盾构施工对邻近管线群影响的室内模型试验,研究隧道盾构垂直下穿多条既有管线时对管线竖向沉降的影响。研究结果表明:当单一管线垂直于隧道开挖方向时,管线最大沉降发生在隧道正上方位置,沉降曲线形态关于隧道轴线呈对称分布,且符合Gauss曲线特征;当隧道垂直下穿双管线时,管线产生的竖向沉降曲线形态与单一管线基本一致,但管线最大沉降值较单一管线明显减小。通过对试验结果的归一化分析,提出管线间距对最大沉降影响的计算公式。

Study on Displacement of Adjacent Pipeline Group Induced by Shield Tunneling

The shield tunneling often causes adverse impact on the adjacent pipeline. The current researches on pipeline displacement are mainly focused on the single pipeline, and the inter-influence among pipeline groups is less addressed. Therefore, an indoor model test of the influence of shield tunneling on the adjacent pipeline group is carried out, and the distribution law of displacement of adjacent pipeline group during the shield tunneling is studied. The results show that when the single pipeline is vertical to the tunnel excavation direction, the maximum displacement of the pipeline takes place above the axis of the tunnel. The settlement curve is symmetrically distributed to the axis of the tunnel, and complies with Gaussian curve pattern; when two pipelines are vertical to the tunnel excavation direction, the displacement curve of the pipelines tends basically to be the same as that of the single pipeline, but the maximum settlement value of the pipeline is obviously smaller than that of the single pipeline. Through the normalization analysis of the experimental results, the formula is proposed to calculate the influence of the pipeline spacing on the maximum settlement.