成层土中竖向荷载作用下超长桩数值模拟
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摘要
根据浙江某金融中心工程实例,建立超长桩在五层土中的桩土作用三维有限元模型,并依据工程试验数据对模型的有效性进行了验证。在竖向工作荷载作用下,随着桩端土弹性模量的增加,超长桩端部承载力的比例增加,桩下部侧摩阻力减小。在桩端土体弹性模量很大时,桩侧摩阻力主要有中部土体提供,桩端部侧摩阻力难以发挥。对土体中的软弱土层,桩侧摩阻力表现出了软化效应。
A 3D finite element model is built to simulate the pile-soil interaction while an over-length pile going through five soil layers according to a financial center project in Zhejiang province, and its effectiveness is verified on the basis of the testing data. Under the vertical working load, the increase of elastic modulus of pile end soil leads to the increased percentage of pile end bearing capacity and the decreased side friction at the lower part of over-length piles. The pile's side friction mainly comes from the middle-layer soil mass instead of the side friction of pile end subject to large elastic modulus of pile end soil. The pile's side friction is of softening effect in a weak soil layer.
A 3D finite element model is built to simulate the pile-soil interaction while an over-length pile going through five soil layers according to a financial center project in Zhejiang province, and its effectiveness is verified on the basis of the testing data. Under the vertical working load, the increase of elastic modulus of pile end soil leads to the increased percentage of pile end bearing capacity and the decreased side friction at the lower part of over-length piles. The pile's side friction mainly comes from the middle-layer soil mass instead of the side friction of pile end subject to large elastic modulus of pile end soil. The pile's side friction is of softening effect in a weak soil layer.
引文
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[5]张忠苗,杨淼,房凯.考虑桩身压缩的综合系数法计算超长桩基础沉降[J].岩土力学,2012,33(3):793-798.
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[8]杨敏,赵锡宏.分层土中单桩分析法[J].同济大学学报,1992,20(4):421-428.
[9]秦世陶,刘蓉,杨喜华.强风化岩石长期稳定性试验研究[C]//2007年湖南水电科普论坛.湖南:2007.
[10]肖宏彬,钟辉虹,张亦静,等.单桩荷载-沉降关系的数值模拟方法[J].岩土力学,2002,23(5):592-596.
[11]Potyondy J G.Skin friction between various soils and construction materials[J].Geotechnique,1961,11(4):339-353.
[12]Randol Ph MF,Wroth C P.Application of the failure state in undrained simple shear to the shaft capacity of driven piles[J].Geotechnique,1981,31(1):143-150.
[13]张忠苗,辛公锋.软土地基超长桩受力性状分析[J].工程勘察,2003,(3):10-13.
[14]王俊杰,朱俊高,魏松.不同桩底地层超长桩工作性能的数值模拟[J].岩土力学,2005,26(2):328-333.
[15]钟闻华,石名磊,刘松玉.超长桩荷载传递性状研究[J].岩土力学,2005,26(2):307-310.
[2]张忠苗,辛公锋.软土地基超长桩受力性状分析[J].工程勘察,2003,(3):10-13.
[3]张齐兴,姚波,俞中齐.超长摩擦桩承载性状的有限元法[J].河海大学学报,2007,35(6):681-685.
[4]尹武先,姚文娟,承泽坤.轴-横向荷载作用下超长桩数值模拟[J].水利水运工程学报,2009,(2):15-20.
[5]张忠苗,杨淼,房凯.考虑桩身压缩的综合系数法计算超长桩基础沉降[J].岩土力学,2012,33(3):793-798.
[6]张忠苗.桩基工程[M].北京:中国建筑工业出版社,2007:89-92.
[7]GB 50010-2010混凝土结构设计规范[S].北京:中国建筑工业出版社,2010.
[8]杨敏,赵锡宏.分层土中单桩分析法[J].同济大学学报,1992,20(4):421-428.
[9]秦世陶,刘蓉,杨喜华.强风化岩石长期稳定性试验研究[C]//2007年湖南水电科普论坛.湖南:2007.
[10]肖宏彬,钟辉虹,张亦静,等.单桩荷载-沉降关系的数值模拟方法[J].岩土力学,2002,23(5):592-596.
[11]Potyondy J G.Skin friction between various soils and construction materials[J].Geotechnique,1961,11(4):339-353.
[12]Randol Ph MF,Wroth C P.Application of the failure state in undrained simple shear to the shaft capacity of driven piles[J].Geotechnique,1981,31(1):143-150.
[13]张忠苗,辛公锋.软土地基超长桩受力性状分析[J].工程勘察,2003,(3):10-13.
[14]王俊杰,朱俊高,魏松.不同桩底地层超长桩工作性能的数值模拟[J].岩土力学,2005,26(2):328-333.
[15]钟闻华,石名磊,刘松玉.超长桩荷载传递性状研究[J].岩土力学,2005,26(2):307-310.