Gentle Driving of Piles (GDP) at a sandy site combining axial and torsional vibrations: Part II - cyclic/dynamic lateral loading tests

Gentle Driving of Piles (GDP) is a new technology for the vibratory installation tubular (mono)piles. Its founding principle that both efficient and low noise emission can be achieved by applying to pile combination axial torsional vibrations. Preliminary development demonstration proposed are main objectives GDP research programme. To this end, onshore medium-scale tests in sand have been performed on piles installed using impact driving methods (including GDP). While results presented Tsetas et al. (2023), work focuses post-installation performance GDP-driven under sequence slow/large-amplitude (cyclic) faster/low-amplitude (dynamic) load parcels. The field data point out influence unsaturated soil conditions, which result complex cyclic stiffness trends due interplay pile–soil gapping soil’s fabric changes. small-amplitude vibrations strongly correlated with previous response large cycles, noticeably frequency-dependent cycles period lower than 1 s. Overall, appears satisfactory, encourages further at full scale.