ASSEMBLY AND ERECTION OF CONCRETE POLE STRUCTURE FOR TRANSMISSION LINES (AS ADVICED on IEEE Std 1025-1993)

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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