MIL-HDBK-1025/5
Anchorage of Covered Floating System.
d)
1) Dolphins are usually used instead of anchor piles.
2) If the water depth is significant, submerged structural
ties across finger ends well below the keel depth of the berthed craft are
sometimes used to strengthen a covered floating system. (See Figure 17.)
Approach Piers and Gangways
2.3.7
General Criteria.
These include the following:
2.3.7.1
Access to the berthing docks and slips from the basin shall be
a)
accomplished by a brow "fixed-pier approach" to a fixed berthing system and by
a hinged gangway to a floating-pier system.
Fixed-pier approach is an extension of the head walk to a
b)
landing on the bulkhead wall or an abutment at the shoulder of a sloping bank.
In floating systems, one end of the gangway shall be supported on floats. It
should be lightweight and only long enough to result in some predetermined
maximum slope (1 on 3) at extreme low water level. For slopes steeper than
1 on 3, a hinged staircase with self-leveling steps shall be provided.
Where the boat basin perimeter is appreciably higher than
c)
maximum high water, the brow shall be ramped down to 1 ft or 2 ft
(.31 - .61 m) above the elevation at its outer end to decrease the slope of
the gangway at low water.
The gangway may be narrower than either the approach pier
d)
(brow) or the main walk.
Length of gangways shall be such that the slope will not be
e)
greater than approximately 1 on 2-1/2 at maximum low water.
Weight of gangways shall be kept as small as possible.
f)
Gangway construction may be of timber, steel, aluminum,
g)
fiberglass, or a combination of these materials. A typical gangway is a pair
of steel or wood stringers with a plywood deck.
Gangways shall have handrails. A 3 ft (.91 m) width between
h)
handrails is the minimum, and 4 to 5 ft (1.2 - 1.5 m) is the minimum if the
pier has multiple berths or if the gangway traffic is heavy. Typical
construction is Warren-truss welded-pipe handrail.
Gangways shall be hinged at the top inside edge of a perimeter
i)
bulkhead wall. If the perimeter is a sloping bank, provide a short fixed-
approach pier to reduce the length and weight of the gangway. The hinge at
the upper end of the gangway shall be of rugged design.
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