Concrete poles are used in constructing transmission and
distribution line structures, and have found to be reliable in doing so. This
article covers the recommended assembly and erection procedures for concrete
pole structures as stated on IEEE Std 1025-1993.
The process will be divided into the following two main
categories:
a) Single-pole structures
b) Framed structures—two or more poles joined by rigid
members
The field assembly and erection methods chosen will be
influenced by such variables as line and structure design, line route, terrain,
climatic or seasonal weather conditions, the impact of any environmental
restrictions, line route access, schedule requirements, and the availability of
critical resources in both manpower and equipment.
Poles that consist of one or more sections are generally
assembled either at the structure site or in a marshalling yard and then
transported to the structure site.
Erection techniques vary greatly depending on the specific
job variables. An erection crane with a telescoping boom is an efficient method
for structure erection. If extensive preassembly is used, the time spent in
final erection is greatly reduced.
Preplanning of desired crane locations at the structure site
allows for any necessary grading work (building of ramps, soil stabilization,
etc.) to be accomplished during the foundation construction operations when
suitable equipment is available at the site. Caution should be used when
cutting into hillsides as this may precipitate slope failures.
Depending on soil conditions, additional bearing support may
be required under outriggers, tracks, and tires. All soil should be returned to
a condition acceptable to the owner after erection.
Aerial lifts can be effective in providing a safe-work
position for workers handling large connection bolts to make aerial
connections. The aerial lift can eliminate the need to install a variety of
either temporary or permanent rigging and climbing devices on each structure.
Whenever possible, efficient field procedures will include
attaching all insulator assemblies on the structure during erection. Stringing
travelers and finger lines installed during erection can greatly expedite the
wire stringing operation.
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