新管幕工法隧道开挖过程风险管理研究

Study on Risk Management during Tunnel Excavation with NTR Construction Method

摘要: 本文依托下穿铁路站场的NTR新管幕工法隧道工程，对不同的隧道横断面形势及施工方案进行了对比分析，探究顶管阶段和开挖阶段的地表沉降规律及结构体系受力特征。研究结果表明：矩形结构形式下地表最大沉降量达到10.66 mm，拱形结构形式下的最大沉降量则为13.84 mm，相比前者地表沉降量增大了29.8%。矩形结构形式下顶管阶段产生的地表沉降量达到总沉降量的69.5%，而开挖阶段产生的沉降量仅占到30.5%；拱形结构形式下由于钢管数量较少，在顶管阶段产生的地表沉降量达到总沉降量的54.9%，而开挖阶段产生的沉降量仅占到45.1%。通过分析可见，从地层沉降控制方面考虑，应优先考虑矩形结构形式。

Abstract: In this paper, based on the NTR new pipe curtain construction method of tunnel engineering under the railway yard, the cross-section situation and construction scheme of different tunnels are compared and analyzed, and the ground settlement law and the stress characteristics of the structural system in the pipe-jacking stage and the excavation stage are explored. The results show that the maximum surface settlement of the rectangular structure is 10.66 mm, while that of the arch structure is 13.84 mm, which increases by 29.8% compared with the former. Under the rectangular structure, the surface settlement in the pipe jacking stage reaches 69.5% of the total settlement, while the settlement in the excavation stage only accounts for 30.5%. Due to the small number of steel tubes in the arch structure, the surface settlement generated in the pipe jacking stage reaches 54.9% of the total settlement, while the settlement generated in the excavation stage only accounts for 45.1%. It can be seen from the analysis that the rectangular structure should be given priority in the ground settlement control.