（上海建科建设监理咨询有限公司 200032）
【提要】结合上海地区25栋高层建筑打入桩基长期沉降观测资料，分析桩端持力层的种类、桩端压缩层砂土比、桩周土层特性以及建筑物施工速率对打入桩桩基长期沉降特性的影响，并探讨了桩周砂土层的存在对软土地区打入桩沉降影响的机理。
【关键词】 打入桩 长期沉降 砂土比 负摩阻力 饱和软粘土
Analysis of Effect Factors on Longterm Settlement of Driven Piles in Shanghai  Highrise Buildings/Zhou Hongbo (Shanghai Jianke Project Management Co., Ltd.,Shanghai 200032,China)
Abstract:Based on the longterm settlement monitoring data of driven piles in twentyfi
ve highrise buildings in Shanghai, the effects of the type of pile toe bearing strata, sand layer depth ratio in compressible layers under pile tip,properties  of soil round the pile shaft and construction speed rate on the longterm settlement characteristics  are analyzed. The mechanisms of effect of the sand layer along the pile shaft on driven pile settlement in soft soil are discussed.
Keywords:driven pile; longterm settlement; sand layer depth ratio; negative skin fricti
on; saturated soft clay