TESTS OF BORED AND DRIVEN PILES IN CRETACEOUS MUDSTONE AT PORT ELIZABETH, SOUTH AFRICA

Three specially constructed test piles were loaded to failure to determine design values for shaft adhesion and end bearing in pile sockets in mudstone. The loading test results were related to strength tests on the rock. Cross-jacking tests in the pile sockets and crushing tests on mudstone cubes correlated well with the pile test results, indicating an ultimate end bearing capacity of nine times the undrained shear strength and an average shaft adhesion factor z=0.2. Unconfined compression tests on cylindrical core specimens appeared to underestimate, and point-load strength tests to overestimate, the mudstone strength. Subsequently some piles were driven into the same mudstone. A loading test on a test pile indicated adequate bearing capacity with much smaller depth of penetration into the mudstone than required for the bored piles. The test showed that the grouted anchor cables developed an adhesion factor z of at least 0.4. (a). This paper forms part of the second geotechnique symposium in print: "piles in weak rock". For the covering abstract of the symposium see IRRD abstract no.220250. /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:
  • Wilson, L C
• Publication Date: 1976-3

Language

• English

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 5-12
• Serial:
  • GEOTECHNIQUE
  • Volume: 26
  • Issue Number: 1
  • Publisher: Thomas Telford Limited
  • ISSN: 0016-8505

Subject/Index Terms

• TRT Terms: Adhesion; Bearing capacity; Bridges; Clay; Conferences; End bearing piles; Load tests; Loads; Mudstones; Pile driving; Rocks; Sediments; Shale; Strength of materials; Structural tests; Support piles; Tests; Undrained shear strength
• Geographic Terms: South Africa
• Old TRIS Terms: Bored pile; Pile tests
• ITRD Terms: 3085: Bearing capacity; 3455: Bridge; 4177: Clay; 8525: Conference; 5567: Load; 3399: Pile; 4154: Rock; 4190: Sediment; 4168: Shale; 8103: South Africa; 6255: Test
• Subject Areas: Bridges and other structures; Construction; Geotechnology; Highways; I53: Construction of Bridges and Retaining Walls;

Filing Info

• Accession Number: 00138921
• Record Type: Publication
• Source Agency: Transport and Road Research Laboratory (TRRL)
• Files: ITRD, TRIS
• Created Date: Oct 26 1976 12:00AM