68th Canadian Geotechnical Conference and 7th Canadian Permafrost Conference

FORMATION OF SOIL PLUGS WITHIN H-PILES DRIVEN IN STIFF CLAYEY PORT STANLEY TILL NEAR LONDON, ONTARIO

Session: Insitu Testing and Instrumentation II / Essais in situ et instrumentation II

Raymond Haché, Stantec Consulting Ltd. (Canada)
Simon Gudina, Stantec Consulting Ltd. (Canada)
Shaun Walker, Stantec Consulting Ltd. (Canada)
Greg MacNeill, Stantec Consulting Ltd. (Canada)

The formation of soil-setup soil plugs within H-Piles is demonstrated using the results of Pile Driver Analyzer (PDA) tests. Sixteen (16) PDA tests were carried out; six (6) on H-Piles driven continuously to 20 m and ten (10) driven after a 24 hours pause to accommodate pile splicing. Test results on piles continuously driven to 20 m demonstrated shaft resistances that agreed with the pre-construction static analysis and showed virtually no scatter in the measured pile resistances. Test results on all piles driven to further depths after welding demonstrated a severe loss of shaft resistance within the top 20 m indicating that a 24 hour delay provided sufficient soil-setup time for the formation of long soil plugs between the flanges which were subsequently dragged down leaving the upper portion of the pile with no reliable soil contact. This paper also demonstrates the use of PDA equipment to develop site specific soil setup functions for predicting long term resistances of friction piles and to investigate unanticipated pile-soil responses.