The inspection and strength checking of old circular prestressed reinforced concrete pole

The capacity expansion of the old transmission lines will lead to an increase in the load level of exsiting prestressed reinforced concrete pole. In this work, the structural parameters of old pole were detected by X-ray imaging technology. The force conditions of the modified concrete pole under the design conditions and actual service conditions were analyzed by Midas/civil. And combined with the calculation of bearing capacity of the circular prestressed reinforced concrete section, the strength checking was conducted. The results showed that X-ray imaging technology can be used to detect the number of steel bars in pole. In addition, the reforming scheme that existing prestressed reinforced concrete poles were used and original LGJ70/10 conductors were replaced with LGJ95/15, still possess considerable safety factor under the actual maximum load conditions.