Lateral Pile-Group Interaction Factors for Free-Headed Pile Groups in Sand from Full-Scale Experiments

Abstract

In order to analyze foundations supported by groups of vertical, pin- headed, laterally loaded piles, it is necessary to include in some rational way the effect of pile-soil-pile interaction, or the increase in pile-head flexibility that occurs in each pile in a group in comparison with an isolated pile. A study was undertaken to measure experimentally pile-head flexibility reduction (interaction) factors in a full-scale pile group in sand. The measurements were accomplished by testing individual piles within a pile group of nine piles cyclically at varying magnitudes of applied ground line shear, two-pile subgroups and three-pile subgroups. The response of certain unloaded piles was also monitored during these individual-pile and small-group tests. Analysis of the results indicated a significant effect of position on flexibility reduction in a two-pile group (leading or trailing) for piles spaced 3 diameters on center and loaded in line and a lesser effect for piles loaded side-by-side. A consistent set of interaction factors was developed from the experiments and applied to the analysis of deflection and shear load distribution in the full nine-pile group, which had been tested earlier on the same test site, through the use of simple matrix techniques.

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1988
Accession Number
ADA197363

Entities

People

  • Mauricio Ochoa
  • Michael W. O'neill

Organizations

  • University of Houston

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Acquisition
  • Actuators
  • Bending Moments
  • Civil Engineering
  • Cone Penetration Tests
  • Data Acquisition
  • Diameters
  • Engineering
  • Engineers
  • Grain Size
  • Internal Friction
  • Load Cells
  • Measurement
  • Mechanics
  • Shear Strength
  • Soils
  • Test And Evaluation

Readers

  • Geotechnical Engineering.
  • Mechanical Engineering/Mechanics of Materials.
  • Organizational Psychology.

Technology Areas

  • Space