液化土层中桩基水平承载特性分析  

Research on lateral resistance of pile foundation in liquefaction strata

作　　者：王建华[1] 冯士伦[1] 

机构地区：[1]天津大学岩土工程研究所,天津300072

出　　处：《岩土力学》2005年第10期1597-1601,共5页Rock and Soil Mechanics

基　　金：国家高技术研究发展计划(863计划)资助项目(No.2002AA615080)。

摘　　要：通过桩土相互作用的振动台模型试验,获得了不同相对密度的砂土在振动液化过程中桩身弯矩随土层振动累积孔压的变化关系。进而通过拟静力方法,确定了土层液化过程中的衰化p-y曲线,并计算出桩身弯矩的分布。计算结果与实测结果的比较分析表明:若土层的振动累积孔压比ru≤0.2时,桩的水平承载能力没有明显降低。当土层的振动累积孔压比ru≥0.8时,若土层的相对密度Dr≤40%,桩的水平承载能力降低90%;若土层的相对密度Dr≥50%,桩的水平承载能力降低75%。Interactions between sands to liquefaction and piles were studied using shake table model tests. The relationships between pile bending moments and cyclic cumulative pore water pressure ratio were obtained for different relative densities sands to liquefaction. Degradation p-y curves of soil-pile interaction were determined during the sand to liquefaction using pseudo-static method. Bending moments along the pile are further calculated using the nonlinear Winkler foundation beam and degradation p-y curves. Calculating and test bending moments were compared. Results show that the lateral resistance of the pile does not reduce if the cyclic cumulating pore water pressure ratio ru≤0.2, it degrades 90 % if the relative density of sands Dr≤40 % and the cyclic cumulating pore water pressure ratio ru≥0.8 and it degrades 75 % if the relative density of sands Dr≥50 % and the cyclic cumulating pore water pressure ratio≥0.8.

关 键 词：桩的水平承载力 砂土液化 桩土相互作用 振动台试验 

分 类 号：TU473[建筑科学—结构工程]