Adjacent construction around metro tunnels is a common situation in urban cities, which usually leads to the disturbance of surrounding soils and existing tunnels. Based on the influence zone theory, construction risks can be described in a graded manner. However, the calculation of the influence zone in existing research is mostly based on a single indicator, which is difficult to adapt to the increasingly stringent requirements of real projects. To address this limitation, a normalized method for the influence function and a weighted combination method for multi-indicators were proposed. These methods can combine any number of indicators to obtain an integrated result of the influence zone, facilitating direct guidance of engineering. Based on a case study of the Metro construction in Qingdao, a series of numerical simulations and calculations of the integrated influence zone was carried out. The results show that the shape of the integrated influence zone in this case is a necked bottle, i.e., the new tunnel causes a greater influence when it is below the existing tunnel. The change of soil layer and the weight of indicators both play important roles on the shape of the influence zone. The relevant conclusions and methods provide a basis for the safety assessment of similar projects.

地铁隧道周边相邻施工是城市中常见的情况，通常会扰动周围的土壤和既有隧道。基于影响区理论，可以对施工风险进行分级描述。然而，现有研究中影响区的计算多基于单一指标，难以适应实际项目日益严格的要求。针对这一局限性，提出了影响函数归一化法和多指标加权组合法。这些方法可以将任意数量的指标组合起来，得到影响区的综合结果，便于工程的直接指导。以青岛地铁建设为例，对综合影响区进行了一系列数值模拟和计算。结果表明，本案例综合影响区的形状为颈瓶状，即新隧道低于既有隧道时影响较大。土层变化和指标权重对影响区的形状均有重要影响。相关结论和方法为类似工程的安全评价提供了依据。