stability As the mast approaches a vertical position,
the permanent guys are fastened to the guy anchors
installed before erection.
Erection, without a davit or gin pole, may be
accomplished by the assembly of the individual
members piece by piece, as the tower is erected. As
assembler, you climb inside the tower and work with the
lower half of your body inside the previously assembled
construction. You then build the web of the tower section
around you, as you progress upward. As each member
is bolted in place, you should tighten all of the
connections immediately so that at no time are you
standing on or being supported by any loose member.
Temporary guying of steel towers is always
necessary where more than one tower section is
erected. Under no circumstances should the tower be
advanced more than two sections without guying.
Permanent guys are to be installed before the
temporary ones are removed.
Several materials, including stranded wire, wire
rope, and fiber line, are all acceptable for temporary
guying. New manila line is the most suitable because
of its strength and ease of handling. The size of the
guyed material required is determined by the height
and weight of the structure to be guyed and by weather
conditions at the installation site.
Secure the temporary guys to the permanent guy
anchors to temporary type anchors or to any nearby
structure that provides the required supporting
strength. Leave the temporary guys in place until the
structure is permanent y guyed and plumbed.
Antenna structures are permanently guyed with
steel cables or fiber glass sections to pre-positioned
anchors according to the installation plan.
Figure 8-37 shows two methods of guying
triangular steel towers. Guys A, B, and C are secured
to a single anchor, while guys D, E, and F are secured
to individual anchors. Both arrangements are
satisfactory. However, the anchor that terminates guys
A, B, and C must be capable of withstanding much
greater stresses than the individual guy anchor
arrangement. Triangular tower guys are arranged so
Figure 8-37.Tower-guying arrangements.
that three guys are spaced 120 degrees apart at each
level of guying (fig. 8-36). Square towers require four
guys spaced 90 degrees apart at each level of guying
(fig. 8-37). Square towers require four guys spaced
90 degrees apart at each guying level. The following
general elevation requirements apply to guy
attachments for towers:
SINGLE-GUY LAYER The cable attachments
are placed in position at approximately two thirds of
the tower height.
TWO-GUY LAYERS. For towers with two-guy
layers, cable attachments are placed in positions at
approximately 30 and 80 percent of the tower height.
THREE-GUY LAYERS. For towers with
three-guy layers, cable attachments are placed in
positions at approximately 25,55, and 85 percent of
the tower height.
Tower Guy Tension
Setting guy tension and plumbing a tower are done
at the same time and only when wind forces are light.
Guy tension adjustment and tower plumbing are done
INITIAL TENSION. All of the guys should be
adjusted gradually to the approximate tensions
specified in the antenna installation details. If tensions
are not specified, guy tension should be adjusted to 10
percent of the breaking strength of the strand of the