关键词: 盾构, 超长桩, 工作性状

Abstract: Shield tunneling passing through adjacent large interchange's super-long piles has negative effect on super-long piles and bridge structures. Numerical analysis is conducted to simulate the process of the shield tunneling passing through the adjacent super-long piles. The bearing performance, deformations and forces of super-long piles caused by the shield tunneling with different depths are investigated. Some conclusions are drawn as follows. Large deformations and forces may occur in piles due to nearby tunneling. The various tunneling locations have different influences on the behaviors of piles. The most unfavorable position for lateral displacement is the upper part of pile; the most unfavorable position for longitudinal displacement is the middle part of pile; the most unfavorable position for vertical displacement is the tip of pile; the most unfavorable position for additional axial force is the lower part of pile, when other conditions are the same. The shaft resistances appear ‘S-shaped’ distribution near the tunnel axis; meanwhile, the maximum axial forces of the piles are also located at the tunnel axis. Lateral and longitudinal deformations of piles that extend to bridge decks are considerable. Horizontal deformations of piles top should be strictly controlled while tunneling passing through adjacent interchange's super-long piles.

Key words: shield tunneling, super-long piles, working performance