Transmission of wave energy through and overtopping of the Long Beach, California breakwater : hydraulic model investigation

Continued)Concern over the resulting wave conditions existing in the channel predicated an agreement between the City of Long Beach,Calif ., and the U. S .Army Engineer Waterways Experiment Station (WES) to conduct two-dimensional wave flume tests to experimentally determine the resulting wave climate in the channel for a range of wave periods and wave heights at different tidal elevations .The experimental breakwater was subjected to this range of wave conditions and the amount of wave energy transmission through and overtopping of the breakwater was recorded at specific locations within the channel .Results are presented in both graphical and tabular form .As part of the U. S. Army Engineer sponsored study of the Los Angeles-Long Beach Harbor compl ex, deepwater wave characteristics approaching the area were propagated numerically into shallow water (to the breakwater) and the effects of refraction and shoaling were determined .The transmission coefficients obtained from this experimental study then were applied to these data, and estimations of the magnitude and duration of specific waves occurring in the channel were developed.Conclusions reached from the study include : a .A physical model of the Long Beach breakwater should be constructed at a scale larger than about 1/40 for the range of vrave characteristics deemed significant in order to eliminate potential scale effects .The scale chosen (1/36) was sufficiently large to eliminate any scale effects in the measured data .