堆载作用下桩基受力特性分析
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摘要
以郑徐(郑州—徐州)高速铁路一特大桥桩侧堆载为背景,采用ABAQUS建立桩-土相互作用有限元模型,研究在不同堆载等级和堆载距离下桩侧摩阻力和桩身轴力的分布规律以及桩顶沉降规律。结果表明:桩侧负摩阻力主要分布在0.57倍桩长范围内,堆载等级越大桩侧摩阻力和桩身轴力越大,负摩阻力最大值出现在0.29倍桩长处,轴力最大值出现在0.52倍桩长处;堆载距离越大桩侧摩阻力和桩身轴力越小,堆载距离大于5倍桩径时,桩侧摩阻力和桩身轴力均明显减小;堆载等级越大堆载对桩基的竖向位移影响越大,堆载距离越大堆载对桩基的竖向位移影响越小。计算结果可以为桩侧堆载控制提供理论依据。
The lateral stack load nearby the pile of the D4 large bridge of the Zhengxu high speed railway line was studied in this paper.The finite element model of pile-soil interaction was established using.The distribution of skin friction and axial force,a nd the settlement of pile top were studied respectively, considering different stack load levels and distances.The results indicate that the negative skin friction is mainly distributed within the range of 0. 57 pile length away from the pile top. The larger surcharge level,the greater negative skin friction and axial force. The maximum negative skin friction appears at 0. 29 pile length and the maximum force occurs at 0. 52 pile length.The greater stack load distance,the smaller skin friction and axial force.When the stack load distance is greater than 5 times of the pile diameter, skin friction and axial force are significantly reduced.Higher level of the stack load leads to more significant effect on vertical displacement of the pile while larger stack load distance results in less influence on the vertical displacement.The calculation results are supportive for the controlling of lateral stack load nearby the pile.
The lateral stack load nearby the pile of the D4 large bridge of the Zhengxu high speed railway line was studied in this paper.The finite element model of pile-soil interaction was established using.The distribution of skin friction and axial force,a nd the settlement of pile top were studied respectively, considering different stack load levels and distances.The results indicate that the negative skin friction is mainly distributed within the range of 0. 57 pile length away from the pile top. The larger surcharge level,the greater negative skin friction and axial force. The maximum negative skin friction appears at 0. 29 pile length and the maximum force occurs at 0. 52 pile length.The greater stack load distance,the smaller skin friction and axial force.When the stack load distance is greater than 5 times of the pile diameter, skin friction and axial force are significantly reduced.Higher level of the stack load leads to more significant effect on vertical displacement of the pile while larger stack load distance results in less influence on the vertical displacement.The calculation results are supportive for the controlling of lateral stack load nearby the pile.
引文
[1]袁灯平,黄宏伟,程泽坤.软土地基桩侧负摩阻力研究进展初探[J].土木工程学报,2006,39(2):53-60.
[2]ABDRABBO F M,ALIN A.Behaviour of Single Pile in Consolidating Soil[J].Alexandria Engineering Journal,2015,54:481-495.
[3]ERGUN M U,SONMEZ D.Negative Skin Friction from Surface Settlements in Model Group Tests[J].Canadian Geotechnical Journa1,1995,32(6):1075-1079.
[4]JEONG S,LEE J,LEE C J.Slip Effect at the Pile-soil Interface on Dragload[J].Computers and Geotechnics,2004,31(3):115-126.
[5]聂如松,冷伍明,魏丽敏,等.堆载对既有桥墩桩基础影响距离分析[J].水文地质工程地质,2017,44(1):64-70.
[6]黄伟达.堆载下被动桩与土体相互作用的FLAC三维分析[J].工程地质学报,2007,15(1):98-102.
[7]董亮,牛斌,谷牧,等.大面积单侧堆载对高速铁路桥梁墩台影响的数值分析[J].铁道建筑,2015,55(1):39-42.
[8]韩东亚,曹平,林杭,等.堆载和桩顶荷载组合作用下的桩土响应分析[J].中南大学学报(自然科学版),2017,48(1):177-183.
[9]杨敏,朱碧堂.堆载下土体侧移及对邻桩作用的有限元分析[J].同济大学学报(自然科学版),2003,31(7):772-777.
[10]盛志强,石玉成,孙军杰,等.基于ABAQUS的竖向荷载下三维桩土沉降变形分析[J].岩土工程学报,2013,35(增1):366-371.
[11]屠毓敏,王建江.邻近堆载作用下排桩负摩擦力特性研究[J].岩土力学,2007,28(12):2652-2656.
[12]杨庆,孔纲强,郑鹏一,等.堆载条件下单桩负摩阻力模型试验研究[J].岩土力学,2008,29(10):2805-2810.
[13]贺嘉,陈国兴.基于ABAQUS软件的大直径桩承载力-变形分析[J].地下空间与工程学报,2007,3(2):306-310.
[14]律文田,冷伍明,王永和.软土地区桥台桩基负摩阻力试验研究[J].岩土工程学报,2005,27(6):642-645.
[15]王波,王保田,张福海,等.膨胀土地基桥台桩基负摩阻力现场试验研究[J].河海大学学报(自然科学版),2006,34(4):447-450.
[2]ABDRABBO F M,ALIN A.Behaviour of Single Pile in Consolidating Soil[J].Alexandria Engineering Journal,2015,54:481-495.
[3]ERGUN M U,SONMEZ D.Negative Skin Friction from Surface Settlements in Model Group Tests[J].Canadian Geotechnical Journa1,1995,32(6):1075-1079.
[4]JEONG S,LEE J,LEE C J.Slip Effect at the Pile-soil Interface on Dragload[J].Computers and Geotechnics,2004,31(3):115-126.
[5]聂如松,冷伍明,魏丽敏,等.堆载对既有桥墩桩基础影响距离分析[J].水文地质工程地质,2017,44(1):64-70.
[6]黄伟达.堆载下被动桩与土体相互作用的FLAC三维分析[J].工程地质学报,2007,15(1):98-102.
[7]董亮,牛斌,谷牧,等.大面积单侧堆载对高速铁路桥梁墩台影响的数值分析[J].铁道建筑,2015,55(1):39-42.
[8]韩东亚,曹平,林杭,等.堆载和桩顶荷载组合作用下的桩土响应分析[J].中南大学学报(自然科学版),2017,48(1):177-183.
[9]杨敏,朱碧堂.堆载下土体侧移及对邻桩作用的有限元分析[J].同济大学学报(自然科学版),2003,31(7):772-777.
[10]盛志强,石玉成,孙军杰,等.基于ABAQUS的竖向荷载下三维桩土沉降变形分析[J].岩土工程学报,2013,35(增1):366-371.
[11]屠毓敏,王建江.邻近堆载作用下排桩负摩擦力特性研究[J].岩土力学,2007,28(12):2652-2656.
[12]杨庆,孔纲强,郑鹏一,等.堆载条件下单桩负摩阻力模型试验研究[J].岩土力学,2008,29(10):2805-2810.
[13]贺嘉,陈国兴.基于ABAQUS软件的大直径桩承载力-变形分析[J].地下空间与工程学报,2007,3(2):306-310.
[14]律文田,冷伍明,王永和.软土地区桥台桩基负摩阻力试验研究[J].岩土工程学报,2005,27(6):642-645.
[15]王波,王保田,张福海,等.膨胀土地基桥台桩基负摩阻力现场试验研究[J].河海大学学报(自然科学版),2006,34(4):447-450.