基于载荷试验的大直径超长桩承载特性分析  

Bearing Behavior Study of Large-diameter and Super-long Pile Based on Full-scale Field Test

作　　者：李永辉[1] 吴江斌[2] 

机构地区：[1]同济大学地下建筑与工程系,上海200092 [2]华东建筑设计研究院,上海200002

出　　处：《地下空间与工程学报》2011年第5期895-902,共8页Chinese Journal of Underground Space and Engineering

基　　金：住房与城乡建设部项目(2009-K3-5)

摘　　要：为研究分析大直径超长灌注桩承载特性,结合上海白玉兰广场工程开展4组试桩现场试验。试桩桩径1 m,桩长85 m,皆为桩端后注浆桩。基于试桩实测数据,分析Q-s曲线以研究其承载变形特性,分析桩体受力以研究其荷载传递规律、桩侧摩阻力分布及桩端阻力发挥性状。考虑桩身材料弹塑性性质,对桩身压缩进行计算分析,计算值与实测结果基本一致,计算结果表明桩身弹性压缩占主要部分,但在高荷载水平下,塑性压缩不容忽视。现场试验研究进一步认识了桩端后注浆大直径超长灌注桩承载机理,为工程实践提供指导和参考。In order to study bearing behaviors of large-diameter and super-long bored pile,4 full-scale filed test piles were introduced in site of Shanghai Baiyulan Square project.The diameter of the piles is 1m and the length of the piles is 85m.The piles are toe post grouted bored pile.According to test results,the bearing-movement characters of the piles are studied based on analyzing Q-s curves.Moreover,the load transfer mechanism,distribution and play characters of the pile shaft friction and play characters of pile toe resistance are studied by analyzing stress of the pile body.The piles are taken as elastic plastic material to calculate the compression of the piles.The difference between the calculated results and test results is small.The calculated results show that the major part of pile compression is elastic compression.But the plastic compression can not be ignored under high loading levels.The bearing mechanisms of large-diameter and super-long bored pile with toe post grouting were further understood by the field test.The pile test also provides guidance for engineering practice.

关 键 词：现场试验 大直径超长灌注桩 承载特性 荷载传递 

分 类 号：TU473.1[建筑科学—结构工程]