浅埋地铁隧道曲线段下穿施工对上方建筑物的影响

Impact of Shallow-buried Metro Tunnel Curve Section Under-passing Construction on Overhead Buildings

目的:青岛地铁13号线嘉陵江路站—香江路站区间在线路转弯处下穿年代久远的建筑物。由于隧道埋深较浅,地层软弱且含水量较大,为达到保障地铁隧道施工过程中的建筑物安全,需进行施工的影响性分析。方法:采用数值计算分析与现场实测相结合,并进行了黏土地层不同含水率下渗透能力测试试验,建立了相应的地层建筑物模型,计算了多个循环开挖进尺工况,以此开展浅埋曲线隧道施工对于既有建筑物的影响分析。结果及结论:黏土的透水能力会受到含水率的影响,表现为含水率越大,透水能力越强;曲线隧道下穿对于既有建筑物的变形具有明显的空间差异,建筑物部分位置变形较大,部分位置出现隆起,这与隧道的穿越方式、建筑物形态等因素有关;隧道开挖到建筑物下方不同位置时,建筑物受到的影响也存在着明显差异;双洞开挖的前后顺序使得变形特征呈现明显的差异。

Objective:The Jialingjiang Road Station to Xiangjiang Road Station interval on Qingdao Metro Line 13 under-passes the long-standing buildings at line curve sections.Due to the tunnel shallow depth,weak stratigraphical conditions and high water content,it is necessary to analyze the potential impact of metro tunnel construction on the safety of adjacent buildings during metro tunnel construction.Method:A combination of numerical calculation analysis and on-site measurements is employed.Permeability tests are carried out under different water content conditions of clay soil layers.Corresponding models of the soil layers and buildings are established to simulate multiple excavation cyclic length working conditions,specifically focusing on shallow-buried curved tunnel construction and its impact on existing buildings.Result&Conclusion:The permeability of clay soil is affected by water content,with higher water content leading to stronger permeability.The under-passing engineering of curved tunnel causes noticeable spatial variation in deformation of existing buildings,and partial area of which experiences more significant deformation and some areas with uplift.These variations are influenced by factors such as the tunnelling mode and the building morphology.The impact on the buildings also varies evidently depending on the tunnel excavation towards different locations beneath the buildings.The sequence of excavation for twin tunnels results in distinct deformation characteristic differences.