Method for evaluating stable rust layer of weather-proof bridge steel in high-salinity marine atmospheric environment

Abstract

The invention discloses a method for evaluating a stable rust layer of weather-proof bridge steel in a high-salinity marine atmospheric environment. The method comprises the following steps: 1) taking samples for later use; (2) carrying out an alternate immersion corrosion test on the groups of weather-proof bridge steel rust layer samples; (3) measuring a capacitance value C0 and a capacitance value Ct of the weather-proof bridge steel rust layer samples before and after the cyclic immersion corrosion test; 4) calculating the absorption rate alpha of a rust layer; 5) preparing the same weather-proof bridge steel rust layer samples after test into a sheet, putting the sheet into a potential testing device, and measuring a potential difference E when the concentration ratio of different solutions is x by a potentiometer; (6) drawing a test result by E-x to obtain a curve slope which is an obstruction factor beta of the weather-proof bridge steel rust layer samples to marine environment corrosive ions; and 7) calculating an evaluation value K, and evaluating the corrosion resistance of the weather-resistant bridge steel rust layer sample according to the value K. The method can be used to effectively evaluate the corrosion resistance of the weather-resistant bridge steel in the high-salinity marine atmospheric environment, and is short in test period and simple and convenient to operate.

Description

technical field [0001] The invention relates to the technical field of stable rust layers of weather-resistant bridge steels, in particular to an evaluation method for stable rust layers of weather-resistant bridge steels in high-salinity marine and atmospheric environments. Background technique [0002] Bridge steel is exposed to the natural environment for a long time, and different degrees of corrosion will cause different degrees of corrosion damage to steel structural parts, thus affecting its safety, reliability and durability. In the atmosphere, the rust layer formed on the surface of carbon steel is loose, with a large number of microcracks and cavities, so it cannot play a very good protective role. The surface of weathering steel will form a dense rust layer, which can prevent the entry of corrosive media, and its anti-atmospheric corrosion performance has obvious advantages compared with carbon steel. Bare installation is the most prominent advantage of weather-r...

AI Technical Summary

Problems solved by technology

[0004] At present, the evaluation methods for evaluating the stability of weather-resistant bridge steel rust layer mainly include visual inspection method, tape adhesion test method, and weekly immersion corrosion test method. These methods are used to evaluate the surface properties of weather-resistant bridge steel rust layer, and the calculated corrosion rate is more The corrosion rate of the matrix with many reactions, for different corrosion environments, especially the marine environment, cannot directly judge the protection ability against Cl- and evaluate the excellent corrosion resistance of the rust layer

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