A 4D investigation of model pile installation

ABSTRACT: Offshore wind turbines are typically fixed to the seabed via open-ended (OE) pile foundations. The risk and cost associated with OE pile installation may be reduced by performing field-scale tests to ensure adequate in-service capacity, as well as gain understanding of installation characteristics for equipment specification. However, to do so is often expensive and in most cases, highly impractical. Instead, 1g small-scale model tests can be used, in part, to study mechanistic behaviour which can aid in validating numerical methods which are capable of scaling to field conditions. In this paper, 1g pile model tests are undertaken in both sand and soft rock and the differing in-situ mechanisms are revealed through novel in-test X-ray techniques with time-resolve enabling a 4D study. The tests presented here are facilitated using a new compact multi-axis loading frame which is operable from within a CT bay.