Scale effects and variability in wave-in-deck type of impact loading more insights into the results of the Breakin JIP

To quantify the loading due to breaking waves, model tests are currently the option of choice. However, it is suspected that scale effects lead to an overestimation of the prototype loading. As such, a typical question in impact load assessment is how conservative load measurements are. To understand how realistic model testing is in this respect, it is necessary to quantify scale effects in the measured loading due to breaking waves as well as to investigate to which extent entrapped air in the wave and during the wave impact is involved. To do so, the BreaKin Joint Industry Project was started in 2016. The objective of the BreaKin JIP was to get more insight into scale effects involved in wave-in-deck model tests and to take first steps towards linking wave kinematics with measured impact loads. During this JIP wave-in-deck model tests were carried out in MARIN’s Depressurized Wave Basin (DWB) at two scales (25 and 50) in atmospheric and depressurized condition. In previous work, a summary overview of these model test results was presented [1]. The current paper provides more in-depth insights into possible sources of scale effects involved in wave-in-deck type of loading, based on further analysis of the existing model test data. It includes a detailed review of a.o. local loads in correlation to the variability of measured (global) impact loads between repeat measurements.