Coastal area concrete reinforcement erosion situation electrochemical test method

Abstract

The invention discloses an electrochemical test method of steel bar corrosion in the concrete of coastal area. The test method comprises the following steps: (1) under the concrete condition of the temperature of 0 to 50 DEG C and the relative humidity of 50 percent to 85 percent, the resistance rate R of the concrete is detected; if the estimated value of R is more than or equal to 20kilo-ohm, the passive film of the steel bar in the concrete is not damaged; if the estimated value of R is less than 20kilo-ohm, the second step is adopted; (2) a silver-silver chloride electrode is used for further determining the corrosion potential of the steel bar; if the estimated value of the corrosion potential of the steel bar is more than or equal to minus 119mV, the passive film of the steel bar in the concrete is not damaged; if the estimated value is less than 119mV, the passive film of the steel bar in the concrete is not damaged. The corrosion current density Jcorr of the steel bar in the concrete is further determined; the average corrosion depth and the average section loss rate of the steel bar are calculated. The guarantee rate of the estimated values is 95 percent. The electrochemical test method has the targeted characteristic and comprehensive criteria, and is in particular suitable for estimating the corrosion of the steel bar in the concrete structure without obvious cracking and rust on the surface.

Description

technical field [0001] The invention relates to a concrete steel bar evaluation technology, in particular to an electrochemical test method for the corrosion state of concrete steel bars, especially an electrochemical test method for the corrosion state of concrete steel bars in coastal areas. Background technique [0002] The steel bars in concrete will corrode after a certain number of years of use, and the concrete structures in coastal areas, such as breakwaters or building structures near the coastline, due to the harsh environment, high humidity and salt content, corrosion of steel bars in concrete is common, and The steel bars in some concrete structures are severely corroded. Therefore, the measurement and determination of the corrosion degree and rate of steel bars in concrete in coastal areas play a key role in the maintenance of buildings. [0003] At present, the commonly used determination methods include concrete resistivity test and steel corrosion potential. ...

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Problems solved by technology

[0007] However, the corrosion current density of steel bars cannot judge the early corrosion of steel bars, especially the judgment of the critical point of steel bar corrosion is not accurate enough, which is not as obvious as the potential method.

Moreover, the on-site test of steel corrosion current density is cumbersome, and its operability is not as good as that of concrete resistivity method and potential method.

[0008] Each individual electrochemical test method has its corresponding traditional criteria. In view of the special environmental conditions in coastal areas, it is found through simulation tests and field tests that the difference in test conditions will have a greater impact on test results. When traditional When the criterion is used, the results measured by different test methods sometimes have conflicts, which is not conducive to the accurate judgment of the corrosion status of steel bars.

It shows that the traditional criteria are not accurate enough for the environmental conditions in coastal areas, and the correlation between different test methods is poor, and a single electrochemical method cannot accurately judge the corrosion state of steel bars

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