沉管灌注桩竖向承载力可靠度分析  

Reliability analysis of vertical bearing capacity of driven-cast-in-place piles

作　　者：黄小娟[1] 赵新铭[1] 孙健 丛日凡 

机构地区：[1]南京航空航天大学土木工程系,江苏南京210016 [2]仁恒置业(南京)有限公司,江苏南京210012 [3]辽宁省凌源市水利局,辽宁凌源122500

出　　处：《浙江工业大学学报》2010年第5期542-545,共4页Journal of Zhejiang University of Technology

基　　金：住房和城乡建设部科学技术基金资助项目(2008-K2-13)

摘　　要：为了研究沉管灌注桩的失效概率,采用无量纲随机变量的极限状态方程,结合南京江北地区沉管灌注桩试桩资料,根据工程桩的竖向荷载—沉降曲线关系表达式来分析和推算单桩竖向极限承载力,用"校准法"对单桩竖向承载力进行可靠度分析.采用MATLAB语言编制了JC法程序计算恒载与办公楼活载、恒载与住宅楼面活载、恒载与风荷载等三种不同荷载组合形式下的可靠指标,在此基础上确定了总抗力分项系数.研究表明:沉管灌注桩的可靠指标较高,反映了现行规范设计的基桩有较高的安全水准,同时可靠指标随着荷载效应比的增大而减小.荷载组合形式对可靠指标的影响不大,且对抗力分项系数的影响也较小.In order to study failure probability of driven-cast-in-place pile,based on the static in situ test data,i.e.P—S relationships of single piles,which were obtained at north bank of the Yangtze River in Nanjing,the vertical ultimate bearing capacities of single piles are estimated by the limit state equation of dimensionless random variables.The reliability of single pile＇s vertical ultimate bearing capacity is analyzed by the method of calibration.Under three different forms of load combination,the reliability index is calculated with JC method in MATLAB language and the partial coefficient of resistance is determined.It is indicated that the higher reliability index reflects the higher safe level of single pile in the current Specifications of Foundations and the reliability index is decreasing with the aggrandizement of loading effect ratio.In addition,the influence of different forms of load combination on reliability index is not remarkable,neither is on the partial coefficient of resistance.

关 键 词：沉管灌注桩 单桩竖向承载力 可靠指标 抗力分项系数 

分 类 号：TU473[建筑科学—结构工程]