【摘要】 盾构超挖引发土体损失,将会对地表产生不同程度沉降。为了探究出土体损失率和隧道中心点沉降值之间的关系,通过盾构超挖模型实验,考虑埋深和土体损失率因素对地表沉降变化规律的影响。研究结果表明:1D、2D和3D位置的土体损失率和隧道中心点的沉降值呈现二次曲线关系且对地表沉降程度呈现逐步变缓的趋势;随着埋深深度的增加,地表隧道中心点的沉降值在减小,在最大土体损失率为12%情况下,随着隧道管埋深位置从1D至3D,隧道正上方地表中心点沉降值从5.86 mm降低至3.55 mm;随着埋深深度和土体损失率的增加,地表沉降槽逐渐增宽并趋于稳定,砂土沉降槽宽度在20 cm-40 cm之间。该结果将对城市交通盾构施工对地表沉降控制提供借鉴作用。更多还原

【Abstract】 Soil loss caused by over-excavation of shield will result in different degrees of settlement on the surface. In order to explore the relationship between the soil loss rate and the settlement value of the tunnel center point,the influence of the buried depth and soil loss rate factors on the surface subsidence change law is considered through the shield over-excavation model experiment. The results show that the soil loss rate at 1 D,2 D and 3 D positions and the settlement value at the center point of the tunnel show a quadratic curve and the degree of surface subsidence gradually slows down;with the increase of the buried depth,the surface tunnel center The settlement value of the point is decreasing. When the maximum soil loss rate is 12%,the settlement value of the center point of the surface of the tunnel is reduced from 5.86 mm to 3.55 mm as the buried depth of the tunnel tube is from 1 D to 3 D. The depth of the buried depth and the loss rate of the soil increase,the surface settlement trough gradually widens and tends to be stable,and the sand subsidence trough width is between 20 cm-40 cm. The result will provide a reference for the control of surface settlement of urban traffic shield construction.更多还原