桩顶荷载对负摩阻力性状影响的现场试验  

Field test of influences of load at pile top on negative skin friction behaviors

作　　者：夏力农[1] 雷鸣[1] 聂重军[1] 

机构地区：[1]长沙学院土木系,长沙410003

出　　处：《岩土力学》2009年第3期664-668,共5页Rock and Soil Mechanics

摘　　要：负摩阻力是桩周土体沉降产生的桩附加沉降和下拽力的综合效应。为了研究不同的桩顶荷载对负摩阻力基桩性状的影响,在同一个试验场地上,对不同桩顶荷载作用下完全相同的3根桩的负摩阻力性状进行了现场测试。测试结果表明,桩顶荷载对于桩的负摩阻力性状有明显影响。随着桩顶荷载的增加,负摩阻力引起的桩附加沉降越大,桩周土体沉降引起的负摩阻力就越小;负摩阻力引起的下拽力也随着桩顶荷载的增加而减小;中性点位置随着桩顶荷载的增加而上升。这对桩基负摩阻力特性的研究是有益的。Negative skin friction is a comprehensive effect caused by additional settlement and dragload of pile induced by settlement of soil surrounding the pile. In order to study influences of different load at pile top on the behaviors of negative skin friction piles, field tests of negative skin friction behaviors of three identical piles with different loads at pile top are made in the same site. Test results show that load at pile top affects negative skin friction behaviors evidently. Additional settlement of pile induced by negative skin friction becomes larger, negative skin friction induced by soil surrounding the pile becomes smaller with the increase of load at pile top. Dragload induced by negative skin friction decreases and position of neutral point in pile moves up while load at pile top increases. It may be useful to the research for negative skin friction behaviors of pile.

关 键 词：桩顶荷载 负摩阻力 影响 试验 

分 类 号：TU473.1[建筑科学—结构工程]