摘要
为探明压实黄土中管桩的承载变形特性,开展了不同类型管桩极限承载力试验和单桩承载力模型试验,获得了不同类型管桩压应力-压缩应变关系曲线、荷载-沉降曲线、桩身轴力和桩侧摩阻力的变化规律。结果表明,管桩压应力-压缩应变关系曲线呈应变软化型,填芯管桩抗压强度较未填芯管桩增加了52.42%,开孔管桩抗压强度较常规管桩损失了7.04%~14.11%;管桩S-Q曲线随荷载增加呈增长趋势,其S-lgQ曲线符合指数函数发展规律;在相同荷载作用下,螺纹管桩沉降量最小,常规管桩次之,开孔管桩最大,螺纹管桩的极限承载力为常规管桩和开孔管桩的1.20和1.35倍;桩身轴力随深度呈“上大下小”分布特征,荷载越大,桩身轴力越大;桩侧摩阻力随深度呈中间大、两边小的“单峰”形特征,开孔管桩桩侧摩阻力最小,常规管桩次之,螺纹管桩桩侧摩阻力最大。研究结果可为压实黄土中管桩的选择和应用提供依据。
To investigate the bearing and deformation characteristics of pipe piles in compacted loess,ultimate bearing capacity tests for different types of pipe piles and model tests on the bearing capacity of single piles were conducted.The variation laws of the compressive stress-compressive strain relationship curves,load-settlement curves,pile axial forces and lateral friction resistance of diverse pipe piles were obtained.The research findings reveal that the compressive stress-compressive strain relationship curves of pipe piles exhibit the strain softening type.Compared with unfilled-core pipe piles,the compressive strength of filled-core pipe piles increases by 52.42%.Meanwhile,in contrast to conventional pipe piles,the compressive strength of perforated pipe piles decreases by 7.04%~14.11%.The S-Q curves of pipe piles demonstrate an upward trend as the load increases,and their S-lgQ curves comply with the development law of the exponential function.Under the same load,the settlement of threaded pipe piles is the smallest,followed by that of conventional pipe piles,and the settlement of perforated pipe piles is the largest.The ultimate bearing capacity of threaded pipe piles is 1.20 times and 1.35 times that of conventional pipe piles and perforated pipe piles respectively.The axial force of the pile body presents a distribution characteristic of being larger at the top and smaller at the bottom with the increase in depth,and the greater the load is,the larger the axial force of the pile body will be.The lateral friction resistance features a“single-peak”shape,with a relatively large value in the middle and smaller values on both sides as the depth increases.The lateral frictional resistance of perforated pipe piles is the smallest,followed by that of conventional pipe piles,and the pile side frictional resistance of threaded pipe piles is the largest.The research results can provide a basis for the selection and application of pipe piles in compacted loess.
作者
邱明明
王法帝
孙苛喆
方涛
段君义
QIU Mingming;WANG Fadi;SUN Kezhe;FANG Tao;DUAN Junyi(School of Civil Engineering and Architectural,Yan’an University,Yan’an 716000;School of Infrastructure Engineering,Nanchang University,Nanchang 330031,China)
出处
《延安大学学报(自然科学版)》
2025年第2期115-120,共6页
Journal of Yan'an University:Natural Science Edition
基金
国家自然科学基金资助项目(52208348)
陕西省教育厅科研计划资助项目(21JC035)
延安大学十四五中长期重大科研项目(2021ZCQ011)
国家级大学生创新创业训练计划项目(202410719004)。
关键词
压实黄土
管桩
模型试验
荷载传递
承载特性
compacted loess
pipe-pile
model test
load transfer
bearing characteristics
