地铁隧道近接下穿城市沉降敏感区影响及优化分析

为研究地铁盾构下穿城市中沉降敏感地区时的沉降特性，基于地铁盾构隧道下穿加油站工程实例，建立三维有限元模型，得到盾构隧道近接加油站过程中地表以及油罐的沉降分布曲线，并进一步通过改变油罐位置，对比分析油罐在不同排列方式下受到隧道开挖的影响。结果表明：在油罐双层布置下，地表沉降随着隧道的掘进而增大，在施工结束后最大沉降达到11.48 mm,靠近左线隧道一侧；油罐在隧道施工的扰动下，其最大沉降达到2.85 mm。油罐单层排列相较于双层布置，油罐的最终沉降减少至2.68 mm;油罐的上下侧的最大沉降差减少了38%,同时油罐表面测点的沉降变化率减少了41%,安全性大幅提升。

Influence and Optimization Analysis of Subway Tunnels Close to and Under the Settlement Sensitive Area

To study the settlement characteristics of subway shield tunneling passing through settlement sensitive areas in cities, a three-dimensional finite element model is established based on the example of subway shield tunneling passing through gas stations. The settlement distribution curves of the ground and oil tanks during the process of shield tunneling approaching gas stations are obtained. Furthermore, by changing the position of oil tanks, the influence of tunnel excavation on oil tanks under different a-rrangement modes is compared and analyzed. The results show that under the double-layer arrangement of oil tanks, surface settlement increases with the excavation of the tunnel, and the maximum settlement reaches 11.48 mm after construction is completed, close to the left side of the tunnel. Under the disturbance of tunnel construction, the maximum settlement of the oil tank reached 2.85 mm. Compared to the double-layer arrangement, the final settlement of oil tanks is reduced to 2.68 mm in the single-layer arrangement. The maximum settlement difference between the upper and lower sides of the oil tank has been reduced by 38%, and the settlement change rate of the surface measurement points of the oil tank has been reduced by 41%, significantly improving safety.