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combined with the structure's confi guration and defl ection under load,
will generate the resulting applied ultimate moment, ultimate shear, ulti-
mate vertical force, and ultimate torsion at each elevation investigated or
at critical points along the pole. The pole's capacity along the length of
the pole shaft shall exceed the combined effect of these values.
All poles shall be designed to withstand the ultimate controlling load
cases as specifi ed.
4.2 Cracking Strength
All poles shall be designed to withstand fi rst crack and crack re-
opening load cases as specifi ed.
4.3 Below Grade Reinforcement
If the pole strength is initially determined by groundline moment, the
Manufacturer shall make certain that suffi cient reinforcing is included in
the portion of the structure that is below grade to resist the increase in
both moment and shear due to specifi ed loads.
4.4 Analysis Assumptions
4.4.1
Free standing poles
: Free standing pole analyses generally will
result in the maximum moment occurring at the groundline, unless
a different point of fi xity is supplied by the Purchaser. The pole
designer must account for the additional P-Delta load when the
Purchaser requires design parameters allowing the pole to translate
and/or rotate in the foundation.
4.4.2
Guyed poles
: In the design of guyed poles, the poles shall be con-
sidered as indeterminate structures and shall be designed as such,
taking the strength and material properties of the poles and guy
wires into account as an integral part of the structure. In making the
analysis for guyed structures, the maximum load applied to the guy
wires shall not exceed 90% of its rated breaking strength or as speci-
fi ed by the Purchaser. The Manufacturer shall advise the Purchaser
if any guy wire sizes initially specifi ed are inadequate.
4.4.2.1 Guyed in one plane: Structures that are guyed in one plane
only shall be treated as free-standing cantilevers in the plane 90°
to the guyed direction and shall have the P-Delta effect consid-
ered in that direction.
4.4.2.2 Guyed on the bisector: For structures guyed on the bisector
or in two directions, a three-dimensional stiffness analysis or
fi nite element analysis shall be made to account for the combined
effects of the various load applications.
4.4.2.3 Guyed structures are plumb: All guyed structures are
assumed to be plumb (no vertical eccentricity in the longitudinal
centerline of the pole) when installed and in service.
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