螺旋挤土灌注桩与长螺旋灌注桩承载力足尺试验研究  

Full scale field load tests on bearing capacity of SDS pile and CFA pile

作　　者：刘钟[1,2] 杨松[1,2] 卢璟春[1,2] 李志毅[1,2] 

机构地区：[1]中冶建筑研究总院有限公司,北京100088 [2]中国京冶工程技术有限公司,北京100088

出　　处：《岩土工程学报》2010年第S2期127-131,共5页Chinese Journal of Geotechnical Engineering

基　　金：国家财政部施工新技术研发项目(财企[2006]376);住房和城乡建设部科学技术项目(2008-K2-40)

摘　　要：为了深入研究新型螺旋挤土灌注桩(SDS桩)和长螺旋灌注桩(CFA桩)在承载变形性状方面的差异性,以在澳大利亚、德国和中国进行的三组承载力足尺对比试验研究成果为依据,对SDS桩相对于CFA桩承载力的提高幅值及其技术优势的内在机理进行了分析与探讨。研究结果表明这种SDS桩新技术适用于各类可压缩土层,而短螺旋挤扩钻头在成桩过程中所产生的挤土正效应,促进了桩周土体物理性能的改进与应力水平的提高,改善了桩周土体的承载变形性能,从而通过提高桩侧摩阻力,达到了大幅度提高螺旋挤土灌注桩极限承载力的目的。In order to study the difference of bearing capacity and deformation properties between soil displacement screw pile and continuous flight anger pile,three results of full scale field load tests from Australia,Germany and China are illustrated.The increased amplitude of bearing capacity of SDS pile compared to CFA pile and the mechanism of technological advantages of SDS pile are analyzed.The research results show that the SDS piling technology is suitable for a wide range of compressible soil conditions,and the positive soil compacting effect induced by short displacement screw auger during piling construction leads to high stress level,which improves the bearing capacity and deformation of soil around pile and therefore enhance the ultimate bearing capacity by increasing friction force on side of pile.

关 键 词：桩基新技术 螺旋挤土灌注桩 挤土效应 承载力 

分 类 号：TU473.1[建筑科学—结构工程]