为保障某城市地铁在富水软弱地层地质条件下近距离下穿高压油管、高压天然气管线以及左、右线密贴的施工安全，对复杂环境下大断面小净距矩形顶管法地铁车站施工风险控制进行研究。介绍超前加固措施、顶管施工参数、密贴施工方法等风险控制措施，选用开挖达95%的“中心大刀盘+两边矩形刀盘式”泥水平衡矩形顶管机；采用顶管井端头地面加固、接收井端头水平加固、顶管段内设置联通通道预留加固孔等一系列加固措施，使顶管总推力、刀盘转矩、泥水舱压力、顶进速度等主要参数实际值严格控制在设定值范围内；通过顶管姿态控制技术、加强同步注浆和二次注浆、后张法预应力钢绞线加强管节纵向刚度措施确保密贴施工。监测数据分析表明： 1）左右线掘进期间，地表沉降为-7.20～0.76 mm，管线沉降为-5.49～3.51 mm； 2）右线密贴施工，地表沉降为-3.64～3.61 mm，管线沉降为-1.45～2.92 mm。

Ensuring construction safety for a metro project in an urban area, particularly when crossing beneath high-pressure oil and natural gas pipelines in water-rich, weak strata, requires robust risk control strategies. The authors examine risk control measures for the construction of large-section, small-spacing rectangular pipe-jacking metro stations. Key measures, including pre-reinforcement techniques, pipe-jacking parameters, and closely adjacent construction methods, are implemented. A slurry-balanced rectangular pipe-jacking machine featuring a central large cutterhead, two rectangular side cutterheads, and an excavation rate of up to 95% is selected. Reinforcement strategies include ground reinforcement at the jacking shaft end, horizontal reinforcement at the receiving shaft end, and reserved reinforcement holes for interconnection channels within the pipe-jacking section. These measures ensure that critical parameters such as total jacking thrust, cutterhead torque, slurry chamber pressure, and jacking speed, remain within specified ranges. By employing jacking posture control technology, enhancing synchronous and secondary grouting, and increasing the longitudinal rigidity of pipe segments through posttensioning of prestressed steel strands, closely adjacent construction is successfully executed. Monitoring data analysis indicates the following: (1) During excavation of the left and right lines, surface and pipeline settlements are controlled within －7.20 to 0.76 mm and －5.49 to 3.51 mm, respectively. (2) During closely adjacent construction of the right line, surface and pipeline settlements are maintained within －3.64 to 3.61 mm and －1.45 to 2.92 mm, respectively.