Document Type : Research Article
In this research the irregular wave transmission from reshaping rubble-mound breakwaters have been investigated. Reshaping breakwaters are recent development in breakwater design, which their initial profiles are changed to a (s) shaped after wave impact. Therefore, the usual relations for transmission coefficients on conventional breakwaters cannot be used for this type of structure.
A comprehensive experimental research was carried out for many sections of reshaping breakwaters with three different slopes in SCWMRI wave flume equipped with a DID wave generation system.
The hydraulic responses of wave transmissions were investigated by changing the wave parameters such as significant wave height, mean and peak wave period and storm duration on three seaward slopes (respectively 1:1.25, 1:2.0, 1:2.5). JONSW AP wave spectrum was used in all experiments. The armor layer materials were used in three grading class (Dn85A/Dn15A=1.14, 1.44, 1.82) and a range of structural permeability, Pe(1£Dn50A/Dn50c£20). IN order to change structural geometry, wave properties and other variables, 100 tests were carried out with 1000 to 6000 waves.
The experimental results showed the relation between transmission coefficients and the new parameter R*. An improved and new relation was achieved using multiple linear regressions.