THE INFLUENCE OF ELECTRO-OSMOSIS ON METALLIC PILES IN CLAY

The stress field around a metallic friction pile in clay can be modified quite drastically by applying a modest, direct current electrical potential across the system with the pile as one electrode. The resistance to penetration of a cathodic pile shaft can be reduced by a factor of at least three and, conversely, that of an anodic pile doubled. Once the pile has been installed, continued application of electro-osmosis appears to increase permanently its load capacity. There is also some evidence, from small scale tests, that, even if the DC potential is disconnected after installing the pile, its load capacity is eventually greater than that of the untreated pile, irrespective of the initial polarity. Although some of these phenomena have been demonstrated previously, at both small and large scale, they have received very little systematic study. In order to obtain reliable experimental data, a series of small field-scale pile tests has been performed in which an elaborately instrumented steel pile was jacked into a clay soil under a variety of applied DC potentials. Load cells measured the stresses acting on the pile while it penetrated the clay both with and without electro-osmosis. The results are presented along with an interpretation of them based on recently published research into the basic mechanism of electro-osmotic (EO) soil consolidation. In addition to investigating the effect of EO during pile driving, further tests were performed to examine its effect some time after installation. These results are also discussed.(a) (TRRL)

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/00168505
• Corporate Authors:

  Institution of Civil Engineers

  One Great George Street, Westminster
  London,   United Kingdom  SW1P 3AA
• Authors:
  • BUTTERFIELD, R
  • JOHNSTON, I W
• Publication Date: 1980-3

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 17-37
• Serial:
  • GEOTECHNIQUE
  • Volume: 30
  • Issue Number: 1
  • Publisher: Thomas Telford Limited
  • ISSN: 0016-8505

Subject/Index Terms

• TRT Terms: Bearing capacity; Clay; Clay soils; Consolidation; Direct current; Electroosmosis; Friction; Metals; Penetration resistance; Pile driving; Piles (Supports); Reduction (Chemistry); Soil stabilization; Soils; Stresses; Tests
• Uncontrolled Terms: Soil consolidation
• Old TRIS Terms: Electroosmotic consolidation; Metal piles; Reduction; Stress conditions
• ITRD Terms: 4177: Clay; 5791: Consolidation (soil); 5785: Electroosmosis; 5452: Friction; 3399: Pile; 5575: Stress (in material); 6255: Test
• Subject Areas: Geotechnology; Highways; I51: Earthworks and Soil Drainage;

Filing Info

• Accession Number: 00315283
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• Files: ITRD, TRIS
• Created Date: Oct 27 1980 12:00AM