15 August 2002
Marking Plates. Provide plates in dock structures marked with their exact
stationing in the dock to facilitate setting of keel and side blocking.
Composition and Marking
. Marking plates should
steel metal plates approximately 203.2 mm (8 in) long by 101.6 mm (4 in) wide set flush
with end anchored into the embedding concrete. Each plate shall be marked
appropriately with centerlines, and with respective distances to the graving dock
centerline and abutment. Figures should be 50.8 mm (2 in) high and permanent.
Location. Marking plates must be laid out accurately. Set marking plates
at the following points:
One on each coping at the drydock entrance.
In both copings at approximately 12.2 m (40 ft) intervals from the drydock
entrance toward head end.
One near the coping edge on the graving dock centerline, at the head end.
One several feet back from the coping edge on the dock centerline, at the
One in the dock floor, several feet to one side of the dock centerline,
sufficient to clear keel blocks, and at approximately 12.2 m (40 ft) intervals
from the drydock entrance coordinated with b) above.
Fenders and Chafing Strips. To protect masonry structures at a dock
entrance, or a caisson berth, provide fenders and/or chafing strips as required. Use
fenders as necessary to protect equipment (such as stairways, ladders, floodlights, and
service outlets) from being fouled by a vessel entering or leaving a dock. Generally,
treated timbers anchored by bolts are used as chafing strips and fenders, but suitable,
rotatable, pneumatic and rubber fenders may also be used. Refer to MIL-HDBK-1025/1
Piers and Wharves for design of fenders.
SHIP BLOCKING. Responsibilities for design and material specification
of ship blocking rests with the Naval Sea Systems Command (NAVSEA). The
information herein is basic guidance; Consult NAVSEA for criteria beyond the planning
Ship Supports. Provide means to keep a docked vessel far enough
above the floor to permit work on its keel, giving allowance for removal or installation of
sonar domes, rudders, propellers, and similar parts. Blocking arrangements are laid out
in the dock in accordance with the docking plan for each individual vessel.
Dog and Side Shores. Long overhangs of vessels are frequently
supported by shores. Shores are wedged against the ship bottom and/or its sides,
either against dock wall altars or against the dock floor.