地面出入式盾构隧道施工地层变形及控制技术研究

Ground Deformation and Control Techniques for Tunneling Using Ground Penetrating Shield Technology

摘要:

传统盾构法隧道需要设置始发井和接收井，限制了其在施工场地有限的城市建筑密集区域应用。地面出入式盾构法（GPST）突破了该限制，无需设置工作井，在地表始发和接收盾构。以上海市高青西路下GPST隧道工程为研究背景，分析了盾构上方覆土厚度不断变化过程中（由浅覆土至超浅覆土）地层变形特征、成因及控制技术的作用效果。研究发现，覆土厚度小于0.4倍隧道直径时，盾构穿越引起地表隆起量超出40 mm，需要施加控制措施；注浆量和注浆压力是影响GPST施工地层变形的关键因素；半堂加固+压重措施对控制地表隆起和管片上浮有一定的作用效果，满堂加固+压重措施的作用效果最好。

Abstract:

Conventional shield tunneling requires the construction of launching and receiving shafts， which limits its applicability in densely built-up urban areas with restricted construction space. Ground penetrating shield technology （GPST） overcomes this limitation by enabling shield launching and receiving directly at the ground surface without working shafts. Taking the GPST tunnel project beneath West Gaoqing Road in Shanghai as the engineering background， this paper meticulously documents and analyzes ground deformation across different overburdens （from shallow to ultra-shallow） encountered by the shield. Subsequently， it discusses the underlying mechanisms and evaluates the control techniques. The results show that when the overburden thickness is less than 0.4 times the tunnel diameter， the tunneling-induced surface heave exceeds 40 mm， and mitigation measures are required. Grouting volume and grouting pressure are identified as the key factors governing ground deformation during GPST construction. The combined application of partial-span reinforcement and surcharge loading provides a noticeable mitigation effect， whereas the full-span reinforcement together with surcharge loading achieves optimal outcomes.