R&D highlights edition 2019

Delta infrastructure 51 R&D Highlights 2019 H ydraulic structures - locks, weirs and storm surge barriers in the main water system and/or the main waterway network of the Netherlands - are important elements for asset managers (such as Rijkswaterstaat and water authorities). These hydraulic structures were built in an era dominated by robust design. In the coming decades, a large number of these hydraulic structures will reach the end of their theoretical design lifespan. Asset managers are therefore facing a future that will be dominated by the replacement and/or renovation of existing structures. The task faced by asset managers is enormous. Logically, options for extending the lifespan of the hydraulic structures, or parts of them, are being studied. Since 2016, Deltares has joined forces with MARIN, TNO and Rijkswaterstaat in themultiyear Knowledge Programme on Hydraulic Structures. The first aim of this research programme is to develop tools that will allow asset managers to use the residual lifespan of hydraulic structures as efficiently as possible. An accurate assessment of the safety of existing hydraulic structures is usually more complex than designing a new robust structure. It requires appropriate analyses of situations involving major uncertainties about future loads, strength variations or rates of strength degradation. The behaviour of a corroded sheet pile wall, including the enlarged soil-structure interaction, was used as a case for expanding the toolbox of the engineer with probabilistic and other methods to deal with these uncertainties. In addition, the programme provides openings for research looking at innovative solutions for new hydraulic structures. Research topics include the validation of Computational Fluid Dynamics for the prediction of the impact on bed protection of an increased propeller outflow, the sensitivity of a valve to vibrations, the discharge coefficient of a weir and the interaction between a vessel and water when the vessel enters a lock. AGING INFRASTRUCTURE: REPLACING HYDRAULIC STRUCTURES EFFECTIVELY AND EFFICIENTLY Since 2016, Deltares has been working with MARIN, TNO and Rijkswaterstaat in themultiyear Knowledge Programme on Hydraulic Structures to develop tools that will enable asset managers to manage the enormous task of replacing and renovating aged hydraulic structures. The research results are available through the programme website. t Sheet pile walls at the construction site of the Sint Andries lock in the 1930s (source: RWS Beeldbank, inventaris nr. RWS-0848) Result of CFD analysis of the sensitivity of a valve to vibrations Measure to prevent excessive salt intrusion through the Krammer­ jacht lock (source: RWS Beeldbank, inventaris 38 Proefvaart Krammerjachtensluis, bellenschermVolkerak-Zoommeerzijde (2)) Finally, the research is focusing on linking the replacement and/ or renovation of hydraulic structures to spatial developments or functional/network adaptation of the infrastructure. The aim is to allow for a well-founded assessment of when an asset manager should proceed with which type of intervention. Efforts have focused on areas such as improving the schematisation of hydraulic structures in networkmodels, the efficient modelling of salt intrusion through locks, supporting guidelines for improved regional analysis and more accurate tools for the assessment of the functional end-of-life of a hydraulic structure. The research results are being made available to the public through the programme website. Contact: Joost Breedeveld, Joost.Breedeveld@deltares.nl , t +31 (0)6 2303 5982 Tom O’Mahoney, Tom.OMahoney@deltares.nl , t +31 (0)6 4691 4637 Further reading : www.nattekunstwerkenvandetoekomst.nl