Impact of Routine Quality Assurance on Reliability of Bored Piles
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 132, Issue 5
Abstract
Quality assurance (QA) tests, such as integrity tests, are routinely conducted to ensure the safety of pile foundations. QA tests provide additional information and result in changes in estimated reliability of pile foundations. This paper aims to formalize a procedure to quantitatively evaluate the impact of routine QA tests on the reliability of pile foundations. Three cases of reliability analyses based on interface coring of large-diameter bored piles are studied; namely, no toe debris detected, toe debris detected without repair, and toe debris detected and repaired. The prior information of the occurrence probability and thickness of toe debris is established based on a practice survey and accumulated QA data. The Bayesian approach is then applied to update the occurrence probability and the mean toe debris thickness based on outcomes of on-site QA tests and remedial actions taken after these QA tests. Subsequently, the reliability of the piles can be updated. The updated reliability can be significantly higher than that before the QA tests. The degree of reliability improvement depends on the pile specifics, the outcomes from the QA tests, and the remedial actions taken after the QA tests.
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Acknowledgments
This research was substantially supported by a grant from the Research Grants Council of the Hong Kong Special Administrative Region (Project No. HKUST6035/02E). The writers would like to thank Mr. Eric Y. W. Wong, MPhil Research Assistant, for conducting the practice survey on quality assurance for bored piles.
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Information & Authors
Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 132 • Issue 5 • May 2006
Pages: 622 - 630
Copyright
© 2006 ASCE.
History
Received: Feb 8, 2005
Accepted: Oct 27, 2005
Published online: May 1, 2006
Published in print: May 2006
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