地铁暗挖站台近距离下穿运营线路施工技术

以珠江三角洲地区某城市地铁11号线暗挖站台隧道近距离下穿地铁运营5号线为例，通过加强超前地质预报，采取超前大管棚、超前小导管对围岩地层进行预注浆加固，主隧道与斜通道CRD法、横通道CD法施工，上半断面悬臂掘进机施工、下半断面控制爆破等相结合的方法，各洞室初支及时封闭成环，顺利穿越了既有地铁5号线，保证了隧道施工安全和地铁运营安全。

Construction Technology of Underground Platform Undercrossing the Line in Operation at Short Distance

Taking the underground platform tunnel of Metro Line 11 which undercrosses the Metro Line 5 at a short distance in a city in the Pearl River Delta as an example, through strengthening the advance geological prediction, adopting the advance large pipe shed and advance small conduit to carry out pre-grouting reinforcement for the surrounding rock stratum, the construction of main tunnel and channel CRD method, cross channel CD method, the construction of cantilever TBM in the upper half section and controlled blasting in the lower half section, and the initial support of each cavern was closed into a ring in time, which successfully crossed the existing Metro Line 5, ensuring the safety of tunnel construction and metro operation.