垂直受荷群桩在半空间饱和土中的稳态反应

研究了均质半空间饱和土中群桩在垂直稳态荷载作用下的动力反应问题。半空间饱和土采用Biot提出的三维波动原理。将桩看作是一维的弹性杆单元。利用圆形简谐载荷作用下的Biot固结方程的基本解和桩土之间的变形协调条件得到饱和土中群桩的第二类Fredholm积分方程，群桩的动力阻抗采用动力相互作用因子的方法。分析桩距等参数对群桩阻抗、轴力和孔压等的影响。本文的方法可以用于计算层状饱和土中群桩的动力反应问题。

Harmonic response of pile groups subjected to vertical load in half space saturated soil

The dynamic response of pile group embedded in homogeneous half space saturated soil and subjected to vertical harmonic load is considered.Biot's three dimensional wave motion theory is applied.The pile can be treated as one dimensional elastic pole unit.A Fredholm's integral equation of the second kind of pile group in saturated soil can be obtained by using the fundamental solutions of Biot's consolidation equation under vertical harmonic disk load and a suitable compatibility condition between piles and soil.The dynamic impedances of pile group are determined by using the impedances of single pile and the dynamic interaction factors.The expression of axial force and pore pressure of pile group in saturated soil can be obtained by using the superposition method.Selected numerical results for vertical impedances,axial force and pore pressure profiles are presented to portray the influence of piles distance.The method can be used to analyze the dynamic response of pile group in layered saturated soil.