ERDC/CHL CHETN-III-64
June 2002 (revised)
DAMAGE DESCRIPTION: The Shore Protection Manual (1984) provides damage as a
function of the marginal wave height exceeding the zero damage wave height. The Shore
Protection Manual damage D% was defined as the normalized eroded volume in the active
region, extending from the middle of the breakwater crest down to one wave height below the
still-water level. This design information is based on laboratory tests limited to monochromatic
nonbreaking waves impinging on long structure slopes. The background reports provide little
insight and no data.
Broderick and Ahrens (1982) provided a definition of damage that was not a function of cross-
sectional geometry. They defined damage to an armor layer by the normalized eroded cross-
sectional area
Ae
S=
(1)
2
Dn50
where
Ae = measured eroded cross-sectional area (Figures 1 and 2)
Dn50 = nominal armor stone diameter
Figure 1. Damaged section parameters
2
Previous Page
