为确保邻近地铁隧道在沉管隧道基槽爆破开挖过程的安全性，通过现场实测评价地铁隧道运营现状，借助数值分析法探索地铁隧道对沉管基槽爆破开挖的力学响应特征，并制定既有隧道结构的安全判据和沉管基槽爆破振动安全距离。研究表明： 既有地铁区间隧道现状累计最大沉降为1.89 mm，近半年最大沉降速率为0.01 mm/d，均小于规范规定的控制值，隧道结构现状处于稳定状态；沉管隧道基槽爆破振动引起的地铁隧道结构最大振速为0.359 cm/s，远小于振速安全阈值（2.0 cm/s），说明地铁结构受爆破振动影响较小，且爆破振动的安全距离为25 m； 基槽开挖应力扰动后引起的地铁隧道累计最大沉降为3.16 mm，小于位移预警值，隧道结构处于稳定状态。

In order to ensure the safety of the adjacent metro tunnels during blasting excavation of foundation trench of the immersed tunnel, the current situation of the metro tunnels are evaluated by field measurement. And then the mechanical response characteristics of the metro tunnels to the blasting excavation of foundation trench are numerically analyzed; and the safety criterion for the existing tunnels as well as the safe distance of the blasting vibration of the immersed tunnel foundation are proposed. The results show that: (1) The accumulated maximum settlement of the existing metro tunnel is 1.89 mm and the maximum settlement rate is 0.01 mm/d in the last half year, which are less than the control values and shows that the tunnel structure is stable. (2) The maximum vibration velocity of the metro tunnel structure caused by blasting vibration of immersed tunnel foundation is 0.359 cm/s, which is significantly less than safe limit 2.0 cm/s and illustrates that the influence of blasting excavation on metro tunnel structure is small; the safe distance of blasting vibration is 25 m. (3) The maximum settlement of the metro tunnels caused by foundation trench excavation is 3.16 mm, which is less than the control value and illustrates that the tunnel structure are in a safe state.