基于土压平衡模式的盾构穿越密集建筑群变形控制技术研究

沈阳地铁4号线劳动路站—望花屯站区间隧道采用盾构法施工,隧道在曲线段穿越密集建筑物群,且建筑物变形控制标准高,隧道穿越地层为富水黏土地层。根据试验段的土压平衡和泥水平衡两种模式掘进效果对比,提出采用土压平衡模式穿越建筑物。详细探讨了穿越过程的盾构掘进参数、土仓压力设定、B型管片注浆孔设置以及曲线段测量控制技术,研制了适合地层特点和盾构结构特点的同步注浆浆液及刀盘开挖轮廓与盾体外缘之间的间隙填充浆液。建筑物变形监测结果表明:隆起及沉降变形均在允许范围内,极大提高了盾构掘进工效。

Deformation Control Technology of Shield Tunneling Under-passing Dense Buildings Based on Earth Pressure Balance Model

The shield tunneling method is adopted in the section between Laodonglu Station and Wanghuatun Station of Shenyang Metro Line 4, and the stratum through which the tunnels pass is the water-rich clay stratum. The tunnels pass through dense buildings in the curved section, and the deformation control standard of the buildings is high. According to the comparison of the tunneling effect of the two modes, the earth pressure balance mode is proposed to pass through the buildings. In this study, the parameters of shield tunneling, the setting of shield earth bunker pressure, the setting of grouting holes of B-type segment, and the measurement and control technology of the curve section are discussed in detail. A synchronous grouting grout suitable for the characteristics of the stratum and the characteristics of the shield structure and the gap filling grout between the excavation contour of the knife disk and the outer edge of the shield are developed. The results of building deformation monitoring show that the uplift and subsidence deformation are within the allowable range, and the efficiency of shield tunneling is also greatly improved.