Model Test on Approaching the Construction of Multi-Line Overlapping Shield Tunnels for Up- and Down-Crossing

Processes

Changzhong Sun¹  Dongfei Lin¹  Shangge Liu¹  Yuanhai Wang¹  Hui Zhou² 

[1] China Gezhouba Group International Engineering Co., Ltd., Beijing 100025, China;Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China;

关键词: shield tunnel;    multi-line overlap;    model test;    formation loss;    ground settlement;   

DOI  :  10.3390/pr10030500

来源: DOAJ

【 摘 要 】

Multi-line overlapping shield tunnels have a complicated layout in the underground space, and the interaction mechanism between tunnels is very complicated. Based on the construction formation of multi-line overlapped shield tunnel with short-distance up- and down-crossing, indoor model tests were conducted to analyze ground settlement (caused by excavation unloading and stratum loss) and the longitudinal deformation law of existing tunnels based on the drainage method, according to the characteristics and control requirements of the short-distance construction of shield tunnels. The results show that as long as the construction strategy of first-down and then-up crossing is adopted, no sudden change in ground settlement would occur. Furthermore, neither the changes in transient settlements nor the final ground settlement would be too large, which is different from the strategy of first-up and then-down crossing; the first-up and then-down crossing strategy generally increases the curvature of the deformation curve of the existing tunnel, and the deformation of the existing tunnel will cause obvious repeated vibrations. This provides theoretical guidance for the design and construction of multi-line overlapped tunnels.

【 授权许可】

Unknown