【摘要】 Y形桩反拱圆弧面侧摩阻力存在不均匀分布现象,侧摩阻力的异形效应导致沉桩过程中的荷载-沉降规律区别于传统桩型,异形效应下的沉降计算单桩极限承载力确定等问题有待研究。通过侧摩阻力、端阻力模型及其产生的附加应力模型,计算不同荷载作用下的桩端沉降,通过荷载-沉降规律预测Y形桩单桩极限承载力。沉降及极限承载力理论计算值与静载试验结果吻合良好。分析了桩长L、外包圆半径R、模板弧度θ、开弧间距s、夹角弧度δ这5个变量对Y形桩沉降及极限承载力的影响,在其他参数不变时,相同桩顶荷载作用下Y形桩单桩沉降随外包圆半径R、开弧间距s、夹角弧度δ、桩长L的增大而减小,随模板弧度θ的增大而增大;Y形桩单桩极限承载力随外包圆半径R、开弧间距s、夹角弧度δ、桩长L的增大而增大,随模板弧度θ的增大而减小。更多还原

【Abstract】 The side friction of Y-section pile is not uniformly distributed along its inverted arch arc,it leads to that the load- settlement law of Y-section pile distinguishes from the traditional piles’ one as there is abnormality effect of side friction. Computation theory of settlement and ultimate bearing capacity of the pile needs to be studied. We calculated the settlements under different loads based on the models of skin friction,ultimate tip resistance and additional stress,then predicted ultimate bearing capacity by loads-settlement laws. The theoretically calculated values of settlement and ultimate bearing capacity are in good agreement with the results of static load test. The influences of five variables : pile length L,radius of outside circle R,formwork radian θ,opening arc spacing s,included angle radian δ on settlement and ultimate bearing capacity of Y-section file were analyzed. The settlements of Y-section pile under the constant load decrease with increase of R,s,δ,L and increase with increase of θ. The influences of corresponding variables on ultimate bearing capacity were also analyzed,the ultimate bearing capacity of Y- section pile decreases with increase of θ and increases with increase of R,s,δ and L.更多还原