riprap stone does not exist in the Arctic(McDonald
Riprap and armor stone
McDonald (1988) discussed the use of quarry
1988). This may be attributed to lack of quarries
stone for slope protection in the northern environ-
and transportation systems along the Beaufort Sea
ment. He cites two examples where stone was used
coast. McDonald (1988) discussed the damage
for slope protection, both in Nome, Alaska. The
caused by the buoyant uplift of submerged ice fro-
first example is the 1067-m- (3500-ft-) long seawall,
zen to stones. He mentioned that loss of stone due
constructed in 1950. It has been overtopped by
to buoyancy of ice is not common and is usually
wind-driven, first-year ice many times without
restricted to small-size stones.
sustaining any damage. The seawall contains
Collins (1988) reviewed the behavior and per-
125,000 tons of granite stone, ranging in size up to
formance of large concrete units for arctic slope
6 tons. The second example is that of jetties built
protection, and found that there is little knowledge
for the Nome Harbor in 1920. These jetties were
of their expected performance in thick ice. He com-
protected with stone, which suffered damage from
mented that the experience of slope protection in
the Great Lakes, Gulf of Labrador, and Gulf of Fin-
storms and ice. These were replaced with steel
sheet pile and concrete jetties in 1939.
land cannot be extrapolated to high Arctic condi-
Experience with the action of multiyear ice on
tions.
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