Overtopping

Mound breakwater overtopping is conditioned by the crest elevation of the structure, the slope exposed to the wave action, the type of piece that forms the main armor unit and its porosity.

Specific overtopping tests have been used to obtain Cubipod armor roughness coefficients.

Yf= 0.46 for single layers

Yf= 0.44 for double layers

The lower the roughness coefficient, the less the overtopping, which also means the crown walls are subjected to lower forces.

Rebase

A Cubipod breakwater crest can be designed using the following equation to calculate the overtopping:

Q =
1 / gH3m0
= 0.2 x exp( 0.53 x lrp - 3.27 x
Ac / Rc
-
2.16 / Yf
x
Rc / Hm0
)

Where Q is the dimensionless overtopping discharge, Rc/Hm0 is the dimensionless freeboard, q [m3/s/m] is the overtopping unit discharge, Hm0 is the significant wave height, Irp = (2Tp /3)/(2πHm0/g)0.5 is the Iribarren number using Hm0 and the peak period (Tp =1/fp ), Rc and Ac are the crown wall and armor elevations, and Yf is the roughness factor. This equation is valid within the range 0.40<Ac/Rc<0.65 for single-layer Cubipod armors, and 0.58<Ac/Rc<0.80 for double-layer Cubipod armors and overtopping 10-6<Q<10-3.