doi:10.16186/j.cnki.1673-9787.2023070047

Received:2023-07-23

Revised:2023-12-05

Online Date:2023-12-06

Study on parallel construction schemes for neighborhood multi-line tunnels（Online）

LIU Li1, ZHANG Zheng2, LIU Jun1, OU Chen1, ZHAO Yingbo1, ZHAO Futian1

1.College of Civil and Transportation Engineering，Hohai University，Nanjing  210098，Jiangsu，China；2.China Railway 24th Bureau Group Limited Company， Shanghai  200040， China

Abstract:Neighborhood multi-line tunnels frequently appear in rail transit engineering， but due to the numerous construction steps and many influencing factors during the excavation process， it is necessary to design a reasonable parallel excavation plan for neighborhood multi-line tunnels. Based on the reasonable excavation methods， this paper adopts two parallel excavation schemes with different excavation sequences. By establishing a three-dimensional finite element numerical simulation model， the surrounding rock stress and displacement between the two schemes are compared. The results indicate that the excavation sequence has a significant impact on the surrounding rocks interaction， with the stress and deformation of middle tunnel being the most affected. The variation pattern of horizontal stress at the arch waist of sequential excavation method and middle tunnel first excavation method is basically consistent， while the vertical stress at the arch crown of sequential excavation method increases by about 40% compared to middle tunnel first excavation method； The horizontal deformation of the arch waist and the settlement of the arch crown of middle tunnel first excavation method increased by 23% and 26% respectively compared to sequential excavation method， but the settlement value in the early stage of middle tunnel first excavation method is relatively small； Taking into account the stress， deformation， and construction period of lining structure， the middle tunnel first excavation method can be used on site， and the rationality of this method can be explained based on the field monitoring results. The above research results can provide reference for design and construction of parallel tunnels with neighborhood multi-line tunnels.

Key words:Neighborhood multi-line tunnels;Numerical simulation model;Sequential excavation method;Middle tunnel first excavation method;Field monitoring

CLC：U455.4