Experimental on grouting reinforcement and treatment ofmetro tunnel basement in collapsible loess(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2022年2期
- Page:
- 91-102
- Research Field:
- 桥梁与隧道工程
- Publishing date:
Info
- Title:
- Experimental on grouting reinforcement and treatment ofmetro tunnel basement in collapsible loess
- Author(s):
- HOU Lele; WENG Xiaolin; HUANG Wenpeng; ZHOU Rongming; LIU Weiping
- Key Laboratory for Special Area Highway Engineering of Ministry of Education,Changan University, Xian 710064, Shaanxi, China
- Keywords:
- tunnel engineering; urban metro; loess area; grouting reinforcement; centrifugal model test; residual subsidence
- PACS:
- -
- DOI:
- -
- Abstract:
- In order to ensure the operation safety of metro tunnels in loess area, a model test system for loess metro tunnel base reinforcement in the form of grouting based on the tunnel project of Xian Metro Line 8 was developed. The centrifugal model test of grouting reinforcement of tunnel base was carried out. The research and development of centrifugal test system mainly from the improvement in the centrifugal model test system of existing immersion device and strain test system, through to the flooding system upgrade and the application of fiber Bragg grating (FBG) test technology of centrifugal test system upgraded, and on this basis to carry out the grouting reinforcement treatment tunnel basement of centrifugal model test. Treatment range, grouting angle and grout strength were taken as the main controlling factors, the influence of the above factors on the tunnel structure bending moment, axial force, surface settlement and vertical displacement of the tunnel were analyzed, so as to evaluate the treatment effect of the tunnel base under different grouting reinforcement control factors. The results show that the grouting reinforcement measures can effectively control the bending moment, axial force, surface settlement and overall vertical displacement of the tunnel. The range of grouting reinforcement, grouting angle and grouting strength have significant effect on controlling the settlement of tunnel base. The larger the grouting range, the larger the grouting angle and the larger the grout strength are, the better the corresponding control of tunnel basement subsidence deformation is. However, if the grouting range, grouting angle and grouting strength are continuously increased, the control effect of tunnel basement deformation is no longer significant. When the thickness of collapsible loess in the basement of metro tunnel is 9 m, it is recommended that the grouting fixation range should be 6 m, the grouting angle should be 150°, and the strength of the grouting slurry should be 50 MPa to allow the residual collapsibility of the basement with a certain thickness. 4 tabs, 19 figs, 26 refs.
Last Update: 2022-04-27