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 When poles are found to be structurally damaged and accompanied by
significant strength loss, repair alternatives versus replacement must al-
ways be considered. New state-of-the-art techniques, using epoxy resins,
fibers, and fillers can restore poles to their original strength [Figure (6)].
When cured, these epoxies are stronger than wood and can also be
drilled, sanded, painted or sawn and be applied to wet surfaces. When
applied in conjunction with preservative supplements for preventing fur-
ther deterioration, poles can be restored to original condition. When
site conditions make pole replacement prohibitively costly, pole restora-
tion can become a viable solution via cost reduction and prevention of
down time. Therefore this should become an available procedure in any
pole maintenance program.
Steel reinforcement splints are also available for restoring pole integrity.
Splints can also be utilized as a temporary repair procedure for emergen-
cy use when poles are mechanically damaged. Replacement or per-
manent repair can then be done during normal working hours rather
than via costly overtime work.
Screening is also available for use on poles that are continuously attack-
ed by woodpeckers, usually caused by territorialism. Territorial poles
may require screening to prevent continuing attack.
7.0 PRESSURE PRESERVATIVE TREATMENTS.
7.1 Introduction. Due to the limited availability and variation in
decay resistance of durable woods such as green heart, cypress, redwood
or cedar, the Navy is required to use relatively non-durable wood that is
treated with preservatives to protect from attack by decay fungi and in-
sects. Preservatives applied to wood by nonpressure processes usually
provide only superficial protection. For maximum protection, all wood
poles world-wide should be initially preservative treated by pressure
processes.
7.2 Incising.
7.2.1 Background. Preservative penetration in
hard-to-treat woods such as Douglas-fir, Western-fir, Western-hemlock,
redwood, and pines that contain a large amount of heartwood, is sig-
nificantly increased by incising wood before treatment [Figure (7)]. The
incisions are commonly 1/4 to 1/2 inch long and deep and about 1/8 inch
wide. For such woods, incising should be specified, non-incised
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