中文摘要：

静压桩贯入地基时，桩侧面与土之间会产生滑动摩擦。采用改进直剪仪进行试验，研究了静压桩与天津滨海新区土体间的滑动摩擦及其时效性，得出了静压桩与土的外摩擦角及其变化规律，并总结了静压桩与土摩阻力的时效性机理。研究发现滑动摩阻力与土的类型、法向应力有关，且与法向应力近似呈直线关系；随着时间的增长，粘土和淤泥质土与桩之间的摩阻力显著增大，且与桩的承载力增长曲线相近。对进一步研究天津滨海地区静压桩的挤土效应和承载力具有一定的参考价值。

英文摘要：

Sliding friction comes into existence between soil and the surface of jaked pile during the process of penetrating. Based on the laboratory test the sliding friction and its time effect between jacked pile and soil in Tianjin Binhai New Area are studied with the improved direct shear apparatus. Angle of external friction and its law between jacked pile and soil are obtained. And the mechanism of time effect is also summarized. The results show that friction resistance is related with soil type, and is approximately linear to the vertical pressure. The increase of friction resistance between pile and clay or mud silt is proportional to the increase of carrying capacity of the pile with the time going by. It has some reference significance for the research on soil compaction effect and carrying capacity of the jacked pile in Tianjin Binhai New Area.