中文摘要：

传统的Poulos弹性理论法基于弹性半空间的Mindlin解,仅适用于弹性半空间中的群桩分析,无法考虑土的层状特性。通过引入层状弹性半空间中轴对称问题的应力和位移解答,将群桩的相互作用系数方法推广到层状弹性半空间中。首先采用有限差分法推导了层状弹性半空间中单桩和两根桩的解答,然后运用Poulos提出的相互作用系数方法考虑桩与桩的相互作用,进而给出了层状弹性半空间中群桩的竖向沉降分析过程。算例分析表明：在弹性半空间群桩分析中,与Poulos的相互作用系数方法和Butterfield和Banerjee的边界元方法结果吻合较好,在双层地基群桩分析中,与Chin和Chow基于双层地基精确解的边界元方法较吻合,与传统弹性理论法相比,本文方法应用范围更广,可用于不等长群桩的沉降分析。

英文摘要：

The classical Poulos’s elastic theory method based on the Mindlin solution in elastic half-space is only suitable for the analysis of pile groups in elastic half-space.It cannot take the layered soil into account.By using stress and displacement solutions of axisymmetric problem in layered elastic half-space,the interaction factor method is extended to the analysis of pile groups in layered elastic half-space.Solutions of a single pile and interaction of two piles in layered elastic half-space are performed by finite difference method firstly.Then the vertical settlement analysis of pile groups in layered elastic half-space is made by considering pile to pile interaction by the Poulos’s interaction factor method.Example analysis shows that the present method agrees with the Poulos’s interaction factor method and the Butterfield and Banerjee’s BEM method in elastic half-space.Calculation of two-layered elastic half-space indicates that the present method is more rigorous than the Poulos＇s interaction factor method,and agrees with the Chin and Chow＇s BEM method,which is based on the accurate solution of two-layered elastic half-space.Besides,the proposed method can be used extensively in the analysis of pile groups with dissimilar piles.