Residual Force. Revisiting Hunter and Davisson (1969)-PPT Presentation

PPT Presentation

Pdf Summary

Bengt H. Fellenius revisits the 1963 full-scale pile tests conducted for Arkansas River Lock and Dam 4 and their analysis by Hunter and Davisson (1969), an influential early study of instrumented pile behavior.<br /><br />The presentation explains how residual forces—locked-in forces remaining in a pile after installation and unloading—can distort measured load-transfer profiles and apparent pile capacity. It distinguishes the “false” force distributions recorded in tests from the “true” response corrected for residual force, and outlines how push and pull test sequence and incomplete mobilization of shaft resistance affect that correction.<br /><br />Fellenius reanalyzes the original test records, comparing the published interpretations with revised force distributions and load–movement curves. The analysis suggests that residual forces alter the apparent shaft and toe contributions to capacity and can affect interpretations of pile response. It also compares impact-driven, vibrated, and jetted piles. Hunter and Davisson had concluded that vibratory installation produced lower shaft resistance than impact driving; Fellenius argues that the available test records do not support this conclusion.

Keywords

Bengt H. Fellenius

pile tests

Arkansas River Lock and Dam 4

Hunter and Davisson

residual forces

load-transfer profiles

pile capacity

shaft resistance

vibratory installation

instrumented pile behavior