The load transfer behavior of piles caused by nearby tunneling

• Main Authors: Goa-Hwei Chiang, 江國輝
• Other Authors: Chung-Jung Lee
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/68375579067618795196

碩士 === 國立中央大學 === 土木工程研究所 === 91 === Tunnels are driven nearby or underpass buildings as closely as possible due to the difficulty of land use in rapid transit system construction projects in urban areas. The stress relaxation due to the closure of tail voids on tunnels in soft soils may cause the ground deformations around the tunnel. The ground deformations (including lateral and vertical soil movements) will damage nearby buildings and building protection measures must be properly taken during constructions. The load transfer mechanisms of the piles embedded in the movable soils are considerably complex and need to study in detail. A series of centrifuge model tests have been performed to assess tunneling-induced ground deformations in sandy ground and their effects on adjacent pile foundations. Two topics have been investigated in this study. First of all, the load transfer mechanism (such as bending moment, axial force and pile head deformation) of the piles has been analyzed in the different conditions, including cover-to-depth ratios, and the distance of the pile and the tunnel. Secondly, the load transfer mechanism (such as bending moment, axial force and pile head deformation) for the piles with axial load has been analyzed in the different conditions, including the cover-to-depth ratios, and the distance of the pile and the tunnel. According to results of the research, tunneling induced the load transfer mechanism of the pile that is affected by the distance of the pile from the tunnel center and the position of the pile tip regarding the horizontal axis of the tunnel center, and the pile with or without load. If the pile with load, that the settlement of the pile is larger than the pile without load. The width of the settlement trough would be suppressed by the pile nearby the tunnel.