Test Research Of The Linear Polarization Method For Inspecting Corrosion Of The Rebar In Concrete

Corrosion of the rebar in concrete is an important factor for the health of the reinforced concrete structures. Linear polarization method is an important electrochemical non-destructive technique, getting the corrosion rate for evaluating the corrosion degree in future. However, the method is seldom used on site projects and with so large differences. It is difficult to use the measurement result for practical maintenance and repair planning of the concrete structure. In addition, there is lack of calibration methods for these non-destructive techniques.This paper is study in using of the linear polarization device GECOR 6. Concrete specimens were made in lab and accelerated for corrosion, making the different corrosion degree. Using the device inspected all of the specimens with different corrosion degree and different corrosion rate. Inspecting all the specimens during the the test periods and found out the method make all the corrosion parameters getting from the device to be stabilization. Get the corrosion parameters in the all test period finding that the logarithm relationship between the corrosion potential and the corrosion rate and the exponential relationship the electrical resistance and the corrosion. Specially, In the end of the test, losing weight is used to calibrate the corrosion rate, finding that there is some error between the non-destructive test and the destructive test and using the corrosion potential modify the corrosion rate can getting the well result and give the experience formula for the future work.Corrosion of the rebar is influenced by so many factors, so the corrosion area and the corrosion depth is a random variable. This paper tries to find the random distribute law of the corrosion area and the corrosion depth. "Gumbel" distribution can meet them well.Research the relationship between half-cell potential measurements and the linear polarization. Get the corrosion rate by the experience formula from the half-cell potential.The GECOR 6 is used in field project. According the experience result from this paper give the evaluation and suggesting for the corrosion of the rebar in concrete columns.This paper give the reference for the detecting the corrosion of the rebar in concrete using linear polarization, specially, for the GECOR 6 is correct used and give the right suggest depend on the result of the corrosion parameters. Specially, the paper is a prework for the recommendation of the inspecting of the corrosion by the linear polariztrion.