Figure A13. Spur with templates removed
The Hudson formula is:
wr H 3
W=
(A8)
K D ( Sr - 1) cotθ
3
where
W = weight of armor material (N)
wr = unit weight of the armor material (N/cu m)
H = design wave height (m)
θ = angle of the structure
K D = stability coefficient of the armor material
S r = specific gravity of the armor material and can be written as
S r = wr / ww , where ww is the unit weight of the water (N/cu m)
To scale for physical modeling purposes, the relationship:
Nwr N H 3
Nw =
(A9)
N KD N( Sr -1)3 Ncot θ
A16
Appendix A
Stability Analysis of a Submerged Spur, North Jetty, Grays Harbor, WA