Ice actions for hydraulic structures of primary flood defense Afsluitdijk - “Applying ISO 19906 at home”

The Afsluitdijk is one of the Dutch Delta programme landmarks. Afsluitdijk is a 32 km long primary flood defense, separating lake IJsselmeer from the Wadden Sea and protecting large areas of the Netherlands against flooding. Over the period spanning 2018 - 2022 the levee will be upgraded by the consortium Levvel (BAM, Van Oord and Rebel). Ice resistance is one of the aspects that is part of the engineering scope of the project. A detailed study on ice actions that apply to the various exposed structural elements is performed, specifically for the hydraulic structures that are integrated in the levee. Dutch regulations with respect to ice actions do specify some levels for ice actions but are not very specific regarding their range of applicability. Ice engineering experience from projects abroad is integrated with Dutch temperate winter conditions, to derive fit-for-purpose ULS and ALS ice actions. The analysis procedure is scenario-based, following the ISO 19906 (2nd ed) limit-stress, limit-force, limit-momentum based approach. This paper describes the study approach and the main results that are obtained.