This paper presents three comparative in situ grouting tests for long-term settlement treatment of a cut-and-cover tunnel of Nanjing Metro Line 10. The characteristics of the tunnel settlement and induced structural damage are described in detail. Comparative grouting tests were conducted to identify the effects of the grouting sequence and grouting material on the tunnel settlement treatment. The test results show that the total amount of uplift of the tunnel associated with the bottom-up grouting sequence is greater than that associated with the top-down grouting sequence. When a mixture of cement and water glass was used as grout, the average cumulative deformation and average deformation rate of the tunnel 6 months after the completion of grouting were −11.2 mm (uplift) and 0.018 mm/day (settlement), respectively. These values satisfy the control requirements and are better than those obtained using a cement and bentonite mixture as grout. Hence, a bottom-up grouting sequence and a cement and water glass grout mixture are advised. The findings presented in this paper provide useful guidance for similar projects.

本文介绍了南京地铁10号线明挖隧道长期沉降处理的三种原位注浆对比试验，详细描述了隧道沉降特征和诱发结构破坏。进行了对比灌浆试验，以确定灌浆顺序和灌浆材料对隧道沉降处理的影响。试验结果表明，自底向上注浆顺序的隧道总隆升量大于自顶向下注浆顺序的隧道总隆升量。当采用水泥和水玻璃的混合物作为灌浆时，注浆完成后6个月隧道的平均累积变形和平均变形率分别为-11.2 mm（隆起）和0.018 mm/天（沉降）。这些值满足控制要求并且优于使用水泥和膨润土混合物作为灌浆获得的值。因此，建议采用自下而上的灌浆顺序以及水泥和水玻璃灌浆混合物。本文中的研究结果为类似项目提供了有用的指导。