The effect of site practices on the integrity of large diameter bored piles

G.C. Fanourakis, P.W. Day, G.R.H. Grieve

In the proceedings of: GEO2011: 64th Canadian Geotechnical Conference, 14th Pan-American Conference on Soil Mechanics and Geotechnical Engineering, 5th Pan-American Conference on Teaching and Learning of Geotechnical Engineering

Session: Deep Foundations

ABSTRACT: In South Africa, concrete in large diameter bored piles is generally placed by discharging a high flow concrete mix directly from the truck mixer and allowing the concrete to fall freely to the base of the pile hole. While certain site practices have been used by piling contractors for years, many engineers are not convinced of their acceptability. This paper discusses the results of an investigation which assessed the effect of site practices on the integrity of cast in-situ bored piles. Such practices include the method of concrete placement and the amount of water and/or loose spoil in the pile hole at the time of casting. The results of this investigation dispel the myth that the free fall placement of concrete in clean, dry pile holes has a detrimental effect on the degree of compaction and compressive strength of the concrete.

RÉSUMÉ: En Afrique du Sud, le béton dans les pieux forés de grand diamètre est placé en renvoyant directement de haut un du pieu. Pendant que certaines methodes ont étées utilisées des années durant par des entrepreneurs, beaucoup d'ingénieurs ne sont du reste pas convaincus de leur acceptabilité. Cet article discute de resultats d'une enquête menée pour évaluer les effets pratiques sur l'intégrité de couler in-situ le béton dans les pieux forés. De telles pratiques incluent forage. Les résultats de cette enquête dissipent le mythe selon lequel le placement par chute libre du béton dans les pieux forés, propres et secs, a un effet préjudiciable sur le degré de compaction et sur la force de compression du béton.

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Cite this article:
G.C. Fanourakis; P.W. Day; G.R.H. Grieve (2011) The effect of site practices on the integrity of large diameter bored piles in GEO2011. Ottawa, Ontario: Canadian Geotechnical Society.

@article{GEO11Paper275,author = G.C. Fanourakis; P.W. Day; G.R.H. Grieve ,title = The effect of site practices on the integrity of large diameter bored piles,year = 2011}