大直径现浇混凝土薄壁筒桩竖向承载力计算研究  

STUDY ON VERTICAL BEARING CAPACITY OF LARGE-DIAMETER CAST-IN-SITU THIN-WALL TUBULAR PILE

作　　者：周建[1] 

机构地区：[1]浙江大学岩土工程研究所,浙江杭州310027

出　　处：《岩石力学与工程学报》2006年第z1期3181-3189,共9页Chinese Journal of Rock Mechanics and Engineering

基　　金：浙江省水利厅科研项目(I40301)

摘　　要：大直径现浇混凝土薄壁筒桩是一种新型桩,已成功应用于高速公路、铁路、水利堤坝、基坑支护工程及民用建筑地基处理中,因其经济效益好、施工速度快、质量有保证、无污染等优点取得很好的经济和社会效应。该桩为端承摩擦桩,如何计算筒桩内、外侧摩阻力是竖向承载力计算中的关键问题,目前这方面的研究很少,各种方法中对是否考虑土芯作用有较大分歧,对端阻力和侧阻力的折减修正也有很大差异,粗略的计算方法导致实测值与计算值相差很大,一般情况下计算值均低于实测值。在筒桩荷载传递机制基础上,对其竖向承载力计算进行探讨,综合利用现有国内外研究成果,对比分析5种计算方法,并通过2个工程实例的静荷载试验进行比较。结果表明,ICP方法简单、实用,与实测值最接近,值得推广应用。Large-diameter cast-in-situ thin-wall tubular pile is a new kind of pile and has been put to wide use in the treatment of soft soil in expressway,dam,embankment,and excavation due to its advantages of cost-saving,fast construction,high quality and less environmental pollution.Usually,the bearing capacity of pile is caused by end-bearing capacity and the frictional resistance between soil and pile.Hence,how to evaluate the outer and inner friction resistances is the key point.So far little progress has been achieved.Whether soil core should be taken into account and how to rectify the end-bearing capacity and friction resistance are still under consideration.This is the main reason that the results deduced from present methods are far away those from the measurement.Based on the load transfer mechanism,five methods from domestic and overseas researches have been analyzed and compared with two case studies.In all these methods,ICP method turns out to be the best one and can be easily used.Its calculation result coincides with the measurement from static loading test,which demonstrates that this method is worthy to be used in practice.

关 键 词：桩基工程 大直径现浇混凝土薄壁筒桩 外侧摩阻力 内侧摩阻力 竖向承载力 

分 类 号：TU473.1[建筑科学—结构工程]