地铁隧道连续穿越高风险环境影响分析和保护措施

Impact Analysis and Protection Measures of Subway Tunnels Continuously Crossing Multiple Risky Environments

地铁盾构施工技术已越来越成熟,但是面临着越来越复杂的周边环境,地铁连续穿越多处风险环境时,对盾构施工技术也提出了更高的要求,难度也大大增加。本文以北京地铁17号线工程为例,盾构隧道连续穿越南水北调东干渠、京津城际铁路及东南五环路等重要风险环境,针对穿越段地层条件及风险环境特征,有针对性地采取相应盾构加固措施,然后采用数值模拟进行计算分析,计算结果显示,隧道掘进对风险工程的影响均在可控范围内。穿越完成后,监测数据显示,各项变形指标均在控制范围之内。施工技术措施合理可靠,成功对风险环境实施了连续穿越,可为类似工程提供借鉴。

The construction technology of shield tunnels is becoming more and more mature,but at the same time,it is also facing an increasingly complex surrounding environments.When the subway continuously crosses through multiple risky environments,higher requirements are placed on the shield construction technology,and the difficulty is also greatly increased.In this paper,the Beijing Metro Line 17 which continuously crosses several important risky environments,the Tunnel of South-to-North Water Diversion,Beijing-Tianjin Inter-City Railway,and the southeast Fifth Ring Road,is taking as an example.According to the ground conditions and risky environment characteristics of the crossing section,corresponding shield reinforcement were applied•Then numerical simulations were performed for calculation and analysis.The calculation results showed that the impact of tunnel excavation on risky environments was within the controllable range.After the completion of the crossing,the monitoring data showed that all the deformation indexes were within the control range.The construction technical measures are reasonable and feasible,and the continuous crossing of risky environments is successfully implemented,which can provide a reference for similar projects.