中文摘要：

通过现场试验研究，对刚性基础与柔性基础下刚性长短桩复合地基桩、土应力及桩土应力比曲线的性状以及桩土应力比随荷载变化的规律及影响因素的作用机制进行了分析．研究表明柔性基础下的复合地基桩土应力比数值比刚性基础下的小，长、短桩桩土应力比差别不如刚性基础突出，反映出基础刚度对复合地基桩土荷载分担特性的影响；刚性基基础下长桩桩土应力比变化比短桩剧烈，其峰值是短桩的3倍左右，且刚性基础下复合地基桩土应力比随荷载变化规律也与柔性基础下的复合地基明显不同．

英文摘要：

Based on the experiment, characters of pile stress, soil stress and pile - soil stress ratio of rigid long- short- pile composite ground under stiff foundation and flexible foundation were investigated. The change law of pile - soil stress ratio and the action mechanism of its affected factors were analyzed. The research indicates that the pile - soil stress ratio of composite ground under flexible foundation and stiff foundation is different sharply. The former is smaller than the latter. The distinction between the stress ratio of long pile and short pile under flexible foundation is indefinite compared with that under stiff foundation. The character of pile - soil load - sharing is affected by stiffness of foundation. Under stiff foundation, the variation of pile - soil stress ratio Of long pile is obvious comparatively, and the peak value of pile - soil stress ratio is three times as much as that of short pile.