AWARD OF MERIT: Special Projects Category

STRENGTHENING OF TUBULAR CENTRIFUGED POSTS

Sao Paulo, Brazil

Submitted by Degussa Construction Chemicals Latin America

The main objective of this repair project was to strengthen reinforced concrete poles. This project was necessary to correct the original design deficiencies that caused a total of eight collapsed concrete telephone poles to date in Brazil. In each of the known collapses, the failure occurred within the development length between the first module (fixed to the ground) and the second module.

Before the companies involved in the project—the repair contractor and the project engineer—learned about this predicament, several posts were removed and replaced by metallic towers. After investigation, the aforementioned team decided to present the owners with an alternative approach: the carbon fiber-reinforced polymer (CFRP) concept, as an ideal solution for their particular case.

The structural solution employed, which was used on 150 poles, was to apply an average of 540 square ft (50 square m) of CFRP system to each pole to be repaired. The heights of these concrete poles varied incrementally from 60 to 197 ft (20 to 60 m).

On average, the rehabilitation cost is approximately 1/3 of the value of the removal and replacement of the post by a metallic tower. This provides an attractive option for the companies in this business both in time and repair costs. It also provides a solution to the design of any additional new concrete poles to be installed in the future, instead of losing the market to metal poles.

Owner
Telesp Celular (VIVO)
Sao Paulo, Brazil

Project Engineer/
Designer
Paula Machado Engenharia de Projectos
Belo Horizonte, Brazil

Repair Contractor
PhDesign Concreto, Construcao e Reabilitacao Ltd.
Sao Paulo, Brazil

Material Suppliers/
Manufacturer
Degussa Construction Chemicals Brazil
Sao Paulo, Brazil