H/d0.78. (14.36)TheShore Protection Manual(US Army, 1984) recommends a formula in
SI units for wave-breaking in shallow water as
H/db aH 0 /gT^2 (14.37)wherea4.46g(1 e^19 s) and b1.561/(1e^ 19.5s),sbeing the beach slope.
Three kinds of breakers, spilling, plunging and surging, as shown in
Fig. 14.9, are distinguished. As a guide, a dimensionless parameter
s/(H 0 /L 0 )0.5 (14.38)is related to the type of breaker (Fig. 14.9).
It is possible for normal approach to relate the wave height and the
depth of water at the location of wave breaking to the conditions upstream
without making detailed refraction calculations. As before, the waveform
at the instant of breaking is considered to be that of a solitary wave
WAVE BREAKING 589
Fig. 14.9 Breaking waves at the beach