Development of a mini vibro-driver for pile testing in the centrifuge

Using vibro-installation to fully install monopiles for offshore wind turbines (OWT) has the potential to mitigate pile run, significantly reduce noise emissions to the marine environment, and decrease project costs. However, due to the inherent complexity of vibro-installation and the limited quantitative data available in the public domain, the mechanisms underpinning vibro-driving are not fully understood. This results in uncertainties in engineering predictions of vibro-drivability and the post-installation performance of monopiles. To address these issues, an innovative mini vibro-driver, designed specifically for use in a geotechnical centrifuge, was developed to study vibro-installation and the lateral loading response of monopiles in sand after installation. The paper outlines the challenges addressed in the design of the vibro-driver, its working principles, and its capabilities. Following this, the results from vibro-driven pile installation tests are discussed and provide an indication of the type and quality of data obtained. These data can contribute to improving the understanding of vibro-driving mechanisms and thereby improve future engineering predictions.