DFI Journal - The Journal of the Deep Foundations Institute
Volume 14, Issue 1, April 2020
DOI: 10.37308/DFIJnl.20181008.189
All Journal papers are free to DFI members.
If you are a member, please click on the "Login" link at the top of this page to to download this paper.
Not a member? Join here to get access to all papers or click the purchase button below to access this paper only.
Analysis of Strain-Gage Records from a Static Loading Test on a CFA Pile
Article Type: Case Study
Fellenius, B. H. & Ruban, T.
Abstract
A static test was performed on a 610-mm diameter, 10 m long CFA pile installed through 3 m of clay and sand and into a thick deposit of lacustrine clay. The loading procedure included prolonged load-holding and an unloading-reloading event, which adversely affected the interpretations of the strain records and demonstrated the inadvisability of not performing a test with equal load-increments and equal load-holding durations and avoiding all unloading-reloading sequences. The pile was strain-gage instrumented at three levels and the recorded strains were used to calculate the pile axial stiffness and deter-mine the load distributions for the applied load. Back-calculations using effective stress analysis were fitted to strain-gage determined load distributions and were then used in simulating the measured pile-head load-movement of the test pile.
Keywords:
static loading test, CFA pile, strain-gage instrumentation, axial stiffness