地铁隧道盾构法施工对桩基变形与内力的影响

通过数值仿真试验,分析了盾构法隧道施工引起的单桩桩身变形、轴力、弯矩随不同的桩洞距离、桩端与水平洞轴线的相对位置、桩型的变化规律,对群桩进行了数值仿真试验。试验结果表明,开挖后桩身发生倾斜变形,桩身内力发生明显变化,且桩端与水平洞轴线的相对位置与桩端土性的不同对桩身内力变化有明显的影响;开挖引起的双桩的桩身内力相对于对应位置的单桩均减小,且由于前桩的遮挡作用,隧道开挖对双桩后桩的影响大大减弱。

Effects of shield tunneling on adjacent existing loaded pile foundations

A numerical analysis is carried out to determine the response of both single piles due to shield tunneling.In the single piles analysis series of factors are considered,namely the distance from pile to tunnel,the pile end position relative to the horizontal tunnel axis,the pile type including friction pile and end bearing pile etc.Numerical results indicate that slip deformations and significant internal forces are induced in adjacent piles due to tunneling.The positions of pile end relative to the horizontal tunnel axis have a larger effect on the deformations and internal forces of adjacent piles.Internal forces is reduced with a certain extent related to that of the single piles located at the equal horizontal distance from the tunnel.And the effects on the rear pile of double piles are more significant due to the shelter from the front pile.