Print Email Facebook Twitter Influence of irregularities in the rock underlayer on the stability of XblocPlus Title Influence of irregularities in the rock underlayer on the stability of XblocPlus Author van den Berg, Ileen (Dutch Process Innovators; Student TU Delft) Hofland, Bas (TU Delft Hydraulic Structures and Flood Risk) Reedijk, Bas (Delta Marine Consultants) Date 2020 Abstract Many rubble mound breakwaters are nowadays made with an armour layer consisting of single layer interlocking elements. The stability of these armour layers could well be influenced by the irregularity of the rock underlayer, as that influences the degree of interlocking. Especially for the new types of regularly placed armour, this might be an important factor for the stability. However, this aspect has not been studied widely yet. Therefore, this paper investigates the influence of irregularities in the underlayer on the stability of a type of single layer breakwater elements. Model tests have been conducted in which the irregularities in the underlayer were systematically varied. The irregularities in the underlayer and the orientations of breakwater elements were measured with 3D-scanning. The breakwater armour unit used in the tests is the XblocPlus. A new failure mechanism, not previously observed for breakwater elements, was found to initiate damage. Causing the armour to be pushed outward by a combined effect of the weight of the upper armour and the excessive hydraulic pressure of the remaining water under the armour layer. Especially large-scale convex (i.e. protruding outwards) undulations in the cross-shore direction influenced the stability of the armour layer. This influence has been quantified. Subject Armour layer stabilityBreakwaterPlacement irregularitySingle-layer unitsXblocPlus To reference this document use: http://resolver.tudelft.nl/uuid:939dc18b-ec8c-482c-8f65-c977e7601890 DOI https://doi.org/10.1016/j.coastaleng.2020.103637 Embargo date 2022-02-01 ISSN 0378-3839 Source Coastal Engineering, 157 Bibliographical note Accepted Author Manuscript Part of collection Institutional Repository Document type journal article Rights © 2020 Ileen van den Berg, Bas Hofland, Bas Reedijk Files PDF 2020_Ileen_vd_Berg_ea_Und ... lus_CE.pdf 13.41 MB Close viewer /islandora/object/uuid:939dc18b-ec8c-482c-8f65-c977e7601890/datastream/OBJ/view