TEKNIK DERGI, cilt.31, sa.3, ss.9941-9966, 2020 (SCI-Expanded)
Variations in mean water level such as tides, seasonal variations, wave set-up/set-down, storm surge and sea level rise due to global warming are directly related to design and performance evaluation of rubble-mound coastal structures. The highest water level is generally considered as the most critical water level for this type of structures. However, Coastal Structures Planning and Design Manual [1] states that the most critical water level can be observed in between the lowest water level and the highest water level. In this study, the effects of different approaches used in selecting design water level on the mass of the armor stone and the free crest height are investigated. Three project sites are selected in the Black Sea, Aegean Sea and the Mediterranean Sea, and the mass of armor stones and the free crest height are calculated at each water level that might be observed during the economic lifetime of these structures. For the selected projects, up to 60% of bigger mass of armor stones are found at lower water levels compared to higher water levels. The results of this study examplifies that the most critical water level can be observed in between the lowest water level and highest water level. In addition, the relation of the most critical water level and the calculation methods of the mass of armor stones are discussed, and it is suggested to assess all the water levels that might occur during the economic life of the structure.