Lifecycle vacuum engagement in suction caissons: penetration, preloading, and preservation

Objective

With the EU targeting over 300 GW of offshore wind capacity by 2050 under the Offshore Renewable Energy Strategy, the development of efficient, reliable, and sustainable foundation systems for diverse marine environments has become an urgent priority. Suction caissons (or anchors), steel hollow cylinders installed by applying vacuum, offer rapid installation, high flexibility, and low environmental footprint, positioning them as highly promising solutions for both fixed-bottom and floating wind farms. However, their full engineering potential remains underexploited due to unresolved challenges in vacuum-soil-caisson interactions across the caisson installation, plug consolidation, and long-term service. This Postdoctoral Fellowship (V-CAISSON) aims to unlock the lifecycle vacuum engagement in suction caissons by investigating how vacuum-induced seepage flow reduces penetration resistance and plug stability, developing and evaluating active vacuum preloading techniques for post-penetration plug enhancement, quantifying the contribution and safe limits of passive vacuum pressure to uplift resistance, and assessing caisson resilience under extreme cyclic and seismic loading. The research bridges geotechnical and structural engineering, soil physics, and fluid mechanics, combining analytical advances with cutting-edge numerical simulations and centrifuge physical modelling. The expected outcomes will deliver a new performance framework for suction caisson foundations that integrates both active and passive vacuum effects, reducing design conservatism and improving deployment confidence. By generating validated models, predictive tools, and design guidelines, V-CAISSON will accelerate the adoption of cost-effective and environmentally friendly foundation systems and strengthen Europe's global leadership in offshore renewable infrastructure, supporting the EU's Green Deal objectives and the transition toward climate-neutral energy.