Bearing Capacity Characteristics of Deep Foundations in Homogeneous Soil under Lateral Loads

横向荷载作用下均质土深基础承载力特性

基本信息

批准号：
03660249
负责人：
KOUMOTO Tatsuya
金额：
$ 1.09万
依托单位：
Saga University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1991
资助国家：
日本
起止时间：
1991 至 1992
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-03660249/
关键词：
Clay Sand Lateral load Rigid pile Flexible pile Deflection Bearing capacity FEM analysis たわみ性杭均一地盤杭水平荷重地盤反力係数たわみ性相対剛性

项目摘要

The deflection and bearing capacity characteristics of model piles (deep foundations) under lateral loads in homogeneous clay and sand have been investigated theoretically and experimentally.Both two-dimensional and three-dimensional model piles which have various flexural rigidity EP (E: elasticity of pile, I: inertia of sectional area of pile) were used for lateral loading tests to obtain the load (P)-horizontal deflection at the free top of piles (y) relationship and the strain distribution on the pile shafts, and to observe the deflection behavior of pile axis under lateral loads.According to the experiment, the Broms's plastic hinges were observed and the places of them approached to the ground surface with decreasing in the value of EI. In the case of clay, when Vesic's dimensionless length betaL which indicated the relative flexural rigidity was less than about 2, piles were considered rigid (short piles), while betaL being greater than about 2, piles were considered flexible (long piles). On the other hand, in the case of sand, when Rifaat's dimensionless length etaL which indicated the relative flexural rigidity as in clay was less than about 2, piles were considered rigid (short piles), while etaL being greater than about 4, piles were considered flexible (long piles).In the region of the plastic deformation, P/D (D:breadth of pile)-y relationships were expressed as straight lines on the double logarithmic plots as expected by the FEM analysis in which the soil was considered elastic. The experimental values of ultimate lateral bearing capacity for both short and long piles in clay and sand were in good agreement with the calculated values by the Broms's theory.

已经在理论上和实验中研究了模型桩（深层基础）的偏转和轴承能力特性（深层基础）。二维和三维模型桩都具有各种弯曲的刚度EP（E：桩的弹性，桩：桩的弹性，i：桩的截面区域的惯性）用于横向加载测试，以获得荷载（p） - 荷叶底挠度（horizontal挠度）在桩的自由顶（y）关系（y）关系和桩轴上的应变分布，并观察挠度根据实验，观察到勃罗姆的塑料铰链，并在EI的值下降时，桩轴的行为。在粘土的情况下，当Vesic的无量纲长度亮键板表明相对弯曲的刚性小于2个时，桩被认为是刚性的（短桩），而Betal大于大约2个，而betal被认为是柔性的（长桩）。另一方面，在沙子的情况下，当rifaat的无量纲长度etal表明相对弯曲的刚度与粘土相对刚性小于2，而堆被认为是刚性的（短桩），而et块则大于4，而堆则大于4被认为是柔性的（长桩）。在塑性变形的区域，p/d（d：堆的广度） - y关系表示为双线在双对数图上的直线，如FEM分析所预期松紧带。粘土和沙子中短桩和长桩的最终侧向轴承能力的实验值与Broms理论的计算值非常吻合。