Instrumentation calibration for model conductors and piles

1. Home
2. Publications
3. Online Library
4. Instrumentation calibration for model conductors and piles

Model piles and conductors have been used for a long time to observe the behaviour and to develop
design methods for different loading systems and soil types. Different levels of instrumentation have been used,
including full bridge strain gauges, shear stress cells, total stress cells and pore pressure cells. This paper details
the instrumentation and the procedures employed to calibrate in the laboratory strain gauges, miniature total stress
cells and pore pressure cells, for vertical and lateral load tests (assessment of bending moment). The sensors were
installed in a 178 mm (7-inch) diameter, 12 mm thick, 6-meter-long steel conductor (open ended pile), embedded
within the pile wall, due to the constraint of keeping internal space enough for the installation of a mud motor. A
special pore pressure device was developed, allowing saturation of the filter to be kept while the conductor has
not yet penetrated in the saturated soil. The constants obtained from calibration after installation of the sensors
in the conductor have been compared with the nominal constants, which are regularly used in practice.
Differences in the range of -7% to +5% were obtained in the case of the strain gauges and -15% to +11% in the
case of the total stress cells and pore pressure cells.

5th International Symposium on Frontiers in Offshore Geotechnics (ISFOG2025)

10 - Jacket pin piles design: capacity, long-term cyclic loading, seismic loads