UFC 4-152-01
28 July 2005
connected together by chocks and wales. A rubber fender unit is mounted
between the wale and the berthing structure. A series of diagonal chains from
the structure to the waler completes the system. Tight-fitting joints between
chocks, wales, and pile head, with proper tension splices that provide
compression and tension continuity along the face of berth must be provided.
Ships may be berthed either directly against fender piles or by using additional
fenders or camels between the ship and the fender piles. When camels are
used, the fender piling must be sized to resist the resulting bending. In the
working stress range, there is an approximate linear relationship between
reaction force and deflection. When used with floating camels, which tend to
cock between the ship and the piles, the ship's energy may become concentrated
on just one or two piles. Hence, unless the floating camel is tightly secured to
the piles (guided by piles), the system will not work well and frequent damage will
occur. The pile-rubber system is not recommended for solid and other types of
piers and wharves where full deflection of the piles within the working range will
be inhibited. When this system is employed throughout the length of berth, the
rubber fender units should be sized for direct berthing of ships (without the use of
camels).
5-3.2.1
Timber Fender Piles.
Timber fender piles have historically been the system of choice. Although timber
fender piles are still in use, environmental concerns coupled with advances in
other fender pile material, have led to a trend in replacement of this type of
system.
5-3.2.2
Steel Fender Piles.
Steel HP sections, wide flange sections and pipes have been used for fender
elements. These pile sections are typically epoxy coated and incorporate a
cathodic protection system. Steel fender piles are typically limited to use with
foam-filled or hydro-pneumatic fenders since they have a limited range of elastic
deflection. The typical steel system is comprised of steel HP sections driven
vertically and connected to a steel wale. The wale is attached to the supporting
structure by a system of rubber fenders and chains. Steel fender systems have
been successfully used. However, due to the additional costs of maintenance
and the cathodic protection systems, their use has been somewhat limited when
compared to other systems. Plastic coated steel pipe has been used for fender
systems in circumstances where large deflections are not anticipated. (Marine
Fender Systems.)
5-3.2.3
Concrete Fender Piles.
Concrete fender piles are the most prevalent system in use. Square prestressed
concrete fender piles have been tested and proven to have high-energy
absorption fendering capabilities and greater strain energy at collapse than either
timber or steel fender piling. They are typically 18- to 24-in2 (1161 to1548 mm2)
prestressed concrete and have served well as primary fender piles for berthing
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