Development and Implementation of an Instrumented Failing Drill for the Predetermination of Pile Bearing Capacity.

摘要

The investigation involved the development and modification of an instrumentation system for the Failing drill for the measurement of the translatory motion of the drill rod during driving,with subsequent data acquisition at selected field sites;and,the development of improved data interpretation procedures on the basis of the static and dynamic features of the drill-rod/soil interaction,with subsequent application to the acquired field data. As a consequence of the high inertial forces of the hammer-drill rod impact for the Failing drill,the lead-wire/attachment arrangement and possibly the motion sensor itself are susceptible to damage during driving. However,the application of a velocity meter for monitoring full-scale pile motion should yield useful information and involve minimal inconvenience when utilized. Procedures for the conversion and interpretation of field data,involving a data transfer from a magnetic tape unit to a PDP-8E computer via analog to digital convertors,were successfully developed and tested.