Abstract
This paper presents the results of the evaluation, diagnosis and repair procedures of galvanized transmission towers localized in a very aggressive tropical marine environment (> C5 ISO 9223).
Initially, it shows an estimate of the damage in magnitude and extent of all the towers, after five years of construction, based on a detailed inspection of two of them and the inspection of a sample of the rest of them. The latter is based on a probabilistic analysis with 95% confidence. All this work allowed the towers with the highest amount of damage to be determined, being them the suggested to be repaired first. In the case of the fasteners, very important pieces to maintain the stability of the different elements of the tower, it was determined (with the same reliability of 95%) the quantity of fasteners to be replaced immediately because of their high degradation (bolts with total loss of the galvanized treatment and severe corrosion of the steel base). It is important to point out that this study quantified all the bolts that need to be replaced per tower, which at the present time is estimated to be over 20% per tower and more than 31% per trunk. Taking into consideration the previous analysis and the environmental data, it can be said that the area where these towers are located is very aggressive. Therefore, coated galvanized steel must be used instead of non-coated galvanized steel.
