中文摘要：

为了探讨考虑剪切变形的PCC桩水平振动特性,首先,采用Timoshenko模型模拟PCC桩,建立其水平振动控制方程;其次,采用微分变换和分离变量法对三维土体控制方程进行解耦,推导出土体位移和水平阻抗解析表达式;然后,结合桩土连续性条件,推导出PCC桩动力复阻抗解析表达式。由此进行算例分析表明：Timoshenko模型与Euler-Bernoulli模型推导的桩顶水平动力复阻抗变化规律一致,验证了解的合理性;复阻抗实部均随桩长增加而减小,虚部均随桩长增加而增大,当桩长增加到临界桩长时,桩长对复阻抗实部和虚部基本没有影响;复阻抗随内径减小而增大,当内径减小至0.2 m及以下时,桩芯土对复阻抗影响不大;当横截面面积相同时,平均半径和壁厚对复阻抗均有显著影响。

英文摘要：

To investigate the horizontal vibrating characteristics of large-diameter pipe piles,a governing equation with Timoshenko model assumed for pipe piles was established. Methods of differential transformations and variable separation were adopted to decouple the three-dimensional equations of soil. The implicit analytical expressions of the soil displacements and horizontal impedances were deduced. Analytical solutions of the pile response were derived based on the assumption of perfect contacts between the pile and soil and thus the expression of the complicated impedances was obtained. On the basis of the analytical solutions,parametric analyses were carried out to find out the most significant factors influencing on the behavior of the horizontal vibrating pipe piles. The results show that the variation of horizontal complex impedances deduced according to the Euler-Bernoulli model agrees well with that deduced from the Timoshenko model,which validates the solution. The real parts of the complex impedances decrease with the increase of the pile length and vice versa for the imaginary parts. Both the real parts and imaginary parts show little variation when the pile length reaches the certain critical value. Although the complex impedances increase with the decrease of the inner radius,their influences on the complex impedances are marginal when the inner radii are less than 0.2 m. Both the average radius and wall thickness of the piles significantly influence the complex impedances when the cross sectional areas are approximately equal.