Experimental Set-up of the Toroid and Hemi-ball Penetrometers

Abstract

The toroid and hemiball penetrometers described in this paper are new site investigation tools that have been developed to measure pipe-soil interaction parameters in situ, at shallow depth in the seabed. This paper reports an experimental program using the new in situ penetrometers, and also a conventional pipe segment, which was conducted at the University of Western Australia. The testing campaign included tests carried out under 1 g and 25 g centrifuge conditions. The 1 g testing were performed on the basis that self-weight effects are essentially negligible for the sliding failure that accompanies axial pipe movements or torsion. The centrifuge toroid testing is considered to provide the most reliable and valuable data to support the deployment of the new penetrometers. The testing was developed to provide data that spans the ranges of toroid/pipe in-service behaviour – including toroid/pipe laying, consolidation after overloading is applied and toroid/pipe axial movement. The focus of the testing program described in this paper was on the further examination of the functionality of the new penetrometer, and to illustrate how much shallow penetrometers could be used for assessing the interaction between pipeline and the seabed.