Interpretation of augered cast in place pile capacity using static loading tests

Abstract

Abstract Instrumented static loading tests present an effective tool for appropriate engineering of piled foundations. Whether instrumented or not, considerable effort can be expended to determine the interpreted failure load developed during the loading test, and the determination of an appropriate capacity is often subject to regulatory review and discussion, which may be complicated by the large number of interpretation methods available and the large range in interpreted capacities that could result. This paper focuses on the differences in the interpreted failure load for augered cast in place (ACIP) piles and seeks to determine which methods are suitable and which methods are inappropriate for the interpretation of ACIP piles. First, a review of various capacity interpretation methods is provided with emphasis on those methods cited in the International Building Code (). Then, an ACIP pile case history database used to illustrate differences in interpreted capacity is described, followed by the presentation of the resulting differences. Recommendations for and against the use of several failure load interpretation methods are made. This paper emphasizes the importance of both the interpretation of the failure load as well as the consequence of a particular methodology on displacement – a critical performance measure.