考虑桩基设计方法的基桩承载力可靠度分析  

Reliability analysis of bearing capacity of foundation piles considering pile foundation design approach

作　　者：边晓亚[1] 郑俊杰[1] 徐志军[2] 

机构地区：[1]华中科技大学岩土与地下工程研究所,湖北武汉430074 [2]河南工业大学土木建筑学院,河南郑州450052

出　　处：《岩土工程学报》2013年第S2期1099-1102,共4页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(51278216);河南工业大学高层次人才基金项目(2013BS010)

摘　　要：桩基设计方法是决定基桩承载力大小的重要因素,不同桩基设计方法的差异性对可靠度分析结果的影响很大。收集了国内外常用的7种桩基设计方法,并以CPT设计方法为基准,利用每种设计方法对应的基桩承载力,定义了各种设计方法的偏差系数,进而给出了考虑不同桩基设计方法的单桩可靠度计算公式。算例分析表明:基桩承载力可靠度水平因桩基设计方法的不同而有较大差异;不同桩基设计方法对可靠度分析结果的影响具有稳定性,为合理选择桩基设计方法提供了依据;由不同桩基设计方法计算得到的可靠度指标数值偏小,差别较大,可用来评价桩基设计方法的安全水平,但不能直接以其数值的大小作为评判基桩可靠性的标准。Pile foundation design approach is an important factor for determining the bearing capacity of foundation piles. The differences between pile foundation design approaches have significant influence on reliability analysis of piles. Seven design approaches for pile foundation are collected for this study, which are widely used at home and abroad. Subsequently, based on the CPT design approach and bearing capacities of piles determined by seven pile foundation design approaches, the bias factor of design approach is defined, and the calculation formula for reliability index of foundation piles considering various design approaches are presented. The results from case study indicate that, the degree to which pile foundation design approaches affect reliability level of pile bearing capacity greatly varies with pile foundation design approaches. However, it is shown the stable impact of pile foundation design approaches on reliability analysis of piles, which supports the proper adoption of pile foundation design approach in practice. Due to that reliability indices based on different pile foundation design approaches are small and have large differences, the reliability indices obtained can be accepted to evaluate the level of safety for pile foundation design approach, but cannot be directly accepted as the criterion to judge pile reliability.

关 键 词：桩 承载力 可靠度 设计方法 偏差系数 

分 类 号：TU473.1[建筑科学—结构工程]