This paper presents the outcomes of a post-installation study performed for the vibrohammer installation of a monopile at a platform located in the Dutch Sector of the North Sea. The monopile diameter was 4.7 m with a length of 40.5 m. The target penetration depth was 31.5 m below seafloor (BSF). The subsoil consisted of very dense fine to medium sands locally with few thin strata of silty sand and sandy silt. During the installation of the monopile, early pile refusal was encountered. The pile installation was subsequently completed using an impact hammer. This paper aims to highlight the importance of monitoring during pile installation and to review key parameters affecting the vibratory driving installation process.
A. Holeyman, V. Whenham, P. Peralta, J.-C. Ballard and S. Chenicheri Pulukul
Keywords: monitoring, vibratory driving, hammer installation, monopile
Publisher: DFI