Numerical Simulation Analysis of the Effectiveness of Initial Support bolts in Mudstone Tunnels

DOI

10.2991/978-94-6463-856-1_23How to use a DOI?

Keywords

mudstone tunnel; system bolts; support effect; numerical simulation; spatio-temporal effect

Abstract

There has always been significant disagreement in the academic circle regarding the effect of setting system bolts in the initial support of mudstone tunnels. Relying on the medium and thick layer mudstone tunnels of expressways, considering the influencing factors such as the spatio-temporal effect of tunnel construction excavation and the setting parameters of bolts, four finite element calculation model were established to analyze the characteristics such as the deformation and plastic zone of the surrounding rock of the tunnel, the mechanical response and the safety factor of the initial support structure under different working conditions. The following research conclusions were obtained: (1) In the initial support of medium and thick mudstone tunnels, the effect of the system bolts is not obvious. (2) Considering the influence of the spatio-temporal effect of the surrounding rock during tunnel excavation, concelling the system bolts is more conducive to controlling the deformation of the surrounding rock and improving the initial support force state. (3) The verification results of the initial support safety factor for medium and thick layer mudstone tunnels without the installation of system bolts meet the requirements of the specifications, which can ensure the technical safety of the tunnel structure. When the system bolts are cancelled in the initial support of mudstone tunnels, it is necessary to ensure the construction quality of the anchor bolts at the lock feet of the side walls and the early strength of the shotcrete.

Copyright

© 2025 The Author(s)

Open Access

Open Access This chapter is licensed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (http://creativecommons.org/licenses/by-nc/4.0/), which permits any noncommercial use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license and indicate if changes were made.

Download article (PDF)

TY  - CONF
AU  - Xianmin Li
AU  - Zhichun Liu
PY  - 2025
DA  - 2025/09/22
TI  - Numerical Simulation Analysis of the Effectiveness of Initial Support bolts in Mudstone Tunnels
BT  - Proceedings of the 2025 International Conference on Resilient City and Safety Engineering (ICRCSE 2025)
PB  - Atlantis Press
SP  - 230
EP  - 243
SN  - 2352-5401
UR  - https://doi.org/10.2991/978-94-6463-856-1_23
DO  - 10.2991/978-94-6463-856-1_23
ID  - Li2025
ER  -