الفهرس | Only 14 pages are availabe for public view |
Abstract The construction of piled-foundation structure or bridges involves the potential for ground movement caused by pile vertical and lateral loading to affect existing tunnel. Numerical methods are increasingly used in such a problem. The objective of this thesis is to propose a finite element model to simulate Pile-Tunnel interaction and predict pile loading, vertically and laterally, impact on a nearby existing tunnel. Firstly, a three-dimensional finite element model was created using PLAXIS 3D software to simulate tunnel construction procedure. Back analysis of greenfield tunneling case study showed excellent agreement between predicted and field monitored surface settlement. The applicability of the proposed model to Tunnel-Structure interaction analysis was proved by back analysis of building response to tunneling case study. Moreover, pile modeling methods were assessed, and the proposed finite element model was developed to simulate Pile-Tunnel interaction problems. Tunnel construction was simulated under existing group of piles, the results showed that the presented model accurately simulate pile response to tunneling. The validated model was used to perform a set of parametric study to assess the impact of pile loading on an existing tunnel. The results of parametric studies show that pile loading increase bending moment, axial compression force and induce new tension force on tunnel lining with different percentage depending on Pile-Tunnel configuration. An influence zone of Loaded pile effect on existing tunnel is identified by clearance of 2𝑫𝑻 and 𝑯𝑻 /𝑳𝑷 ratio of 1.25. However, lateral load effect is more significant through a clearance of 𝑫𝑻 and 𝑯𝑻 /𝑳𝑷 ratio of 0.50. Lateral load on pile contributes by 50.00% of induced B.M, 10.00% of induced compression axial force, 2.00% of induced tension axial force on tunnel lining and 95.00% of lateral deformation. On the other hand, pile axial load causes about 87.00% of induced vertical deformation of tunnel lining. |