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Coastal Engineering: Theory and Practice
Fig. 8.21 Latéral movement of fender piles due to impact force from berthing
ship (a) Single free-headed pile (b) Group of fixed-headed piles.
8.9 Problems
Problem I
Estimate the wave force and moment on the vertical wall of height 4.5 m
in a water depth of 3 m due to the incident wave height of 1.5 m and the
wave period of 6 sec or 10 sec.
Solution
Given: Wall height, b — 4.5 m; water depth, d = 3 m; wave height, Hi =
1.5 m; wave period, T = 6 sec or 10 sec.
For T = 6 sec,
d
hÈ = 05 Hi .
1,5
3
’ gT2
9.81 x 62
= 0.0043
HFrom Fig. 8.4, for —= 0.0043,
gT
ho
= 0.66,
h0 = O.GQHi = 1.0 m
yc — d 4- h0 +
1+Ær\
2 J Hi = 5.5 m (as Kr is taken as 1)
yt — d + ho —
Hi = 2.5 m
2