3D finite element analysis of large span tunneling in muddy stratum

This paper represents study results of finite-element analyses on the deformation behavior of large span muddy stratum tunnel reinforced by longitudinal pipes, inclined jet and horizontal rotary jet. A 3D finite-element model was used in this study to study the 3D behavior of tunnel by shallow mining. The results indicate that the high pressure jet grouting is used to reinforce the muddy stratum by large volume and can significantly decrease the face deformation, foundation settlement and surface settlement well, and thus improve stability of tunnel face and ground. If fiberglass bolt is used to reinforce the advanced core further ahead of tunnel face, the stratum deformation can be controlled and almost influenced on surrounding buildings and underground pipelines. So deformation of the buildings and underground pipelines can be less during construction. The study results can be used as some guides and references in the process of large span tunneling in muddy stratum.