PILING IN CHALK. SOME PROBLEMS ENCOUNTERED DURING THE CONSTRUCTION OF LARGE DIAMETER BORED CAST IN SITU PILES AT BRIGHTON

The author discusses some of the problems encountered during the construction of large diameter bored cast in situ piles at the site of the new conference and multi-purpose centre at Brighton. The close proximity of adjacent property precluded the use of driven pile foundation methods, and the contractors decided to adopt the following construction technique: open boring of the hole down to just above standing water level, insertion of an approximately full length casing using a casing vibrator, drilling out under water kept artificially high by additional pumping, placement of concrete by the tremie technique and finally the extraction of the casing again using vibration. All the piles had 3 M long nominal starter bars inserted after the casing had been withdrawn, except those piles which carried the main columns: they contained nominal full length cages of longitudinal steel. The boring operations had to be revised when it was observed that during the concreting of a 750 mm dia. pile the volume of concrete being placed (18 cu M) prior to the casing being removed far exceeded the theoretical volume (7.6 cu M). Investigative and remedial measures to overcome concrete slumping during tremie operations are discussed. The author concludes that these problems emphasize the need for very close control over the volume of placed concrete compared to the theoretical volume, and the necessity of using a rich high slump concrete when using the tremie technique. /TRRL/

  • Availability:
  • Corporate Authors:

    Foundation Publications Limited

    7 Ongar Road
    Brentwood CM15 9AU, Essex,   England 
  • Authors:
    • Rennie, I A
    • McDonald, C M
  • Publication Date: 1976-4

Language

  • English

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 14-18
  • Serial:
    • GROUND ENGINEERING
    • Volume: 9
    • Issue Number: 3
    • Publisher: EMAP CONSTRUCT LIMITED
    • ISSN: 0017-4653

Subject/Index Terms

Filing Info

  • Accession Number: 00142127
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Report/Paper Numbers: Analytic
  • Files: ITRD, TRIS
  • Created Date: Jul 19 1977 12:00AM