Quantification of Tafel coefficients according to passive/active state of steel carbonation‐induced corrosion in concrete

Abstract

Statistical quantification of Tafel coefficients is investigated in this study for isolated steel rebar embedded in concrete. The survey is supported by a wide experimental campaign carried out earlier to characterize the passive and active states of carbonation‐induced corrosion of steel. Electrochemical measurements (polarization resistance, corrosion potential, Tafel coefficients) and gravimetric estimations of iron loss were regularly conducted over 417 days on 108 concrete specimens. The statistical analysis reveals that the mean value of Tafel coefficients, both cathodic and anodic, is higher under active corrosion, which seems to contradict the general tendency found for chloride‐induced corrosion, while their coefficient of variation is smaller. The statistical inference was based on the first step of distributions fitting the experimental data and then on the second step of goodness‐of‐fit tests. The most suitable of the distributions proposed were the Burr, Rayleigh, and Gamma distributions. A similar analysis was made for the corrosion potential and polarization resistance. The findings of the study will be valuable for probabilistic approaches to corrosion where probabilistic distributions are required.

Electrochemical corrosion parameters for active and passive reinforcing steel in carbonated and sound concrete

“…However, Duprat et al [ 19 ] reported a mean value of of 868 mV/dec in carbonated samples, these values are very high considering the active corrosion state of steel rebars. The geometry of the samples in the case of Duprat et al [ 19 ] was very different than what is employed in this study. They reported the parameters on steel rebar embedded in block samples, such geometry does not allow for uniform polarization of the whole steel surface.…”

“…Hence, electrochemical corrosion parameters are expected to be dissimilar. Duprat et al [ 19 ] reported the corrosion parameters in carbonated and noncarbonated concrete. The mean values of and , were 868 and 473 mV/dec for active steel in carbonated concrete, respectively, whereas, for the passive steel, the values were 637 and 218 mV/dec, respectively.…”

Indirect Galvanostatic Pulse in Wenner Configuration: Numerical Insights into Its Physical Aspect and Its Ability to Locate Highly Corroding Areas in Macrocell Corrosion of Steel in Concrete

“…β ), and the rebar potential E [48,49]. The oxygen concentration was not implemented in the Butler-Volmer equation as its reduction is suspected to be the rate-determining step only when all dissolved and gaseous O 2 is depleted within concrete, which occurs only after a long period under permanent saturation [50,51].…”

“…Without knowing the charge-transfer coefficients, an error will be introduced during calculation of the corrosion rate. However, according to experimental values of β a and β c in the literature [5,48,49,88,89], this error should be a factor of 10 at most when the charge-transfer coefficients are unknown.…”

Steel Corrosion Evaluation of Basalt Fiber RPC Affected by Crack and Steel-Concrete Interface Damage Using Electrochemical Methods

“…Monzon et al [ 32 ] studied the corrosion rate of reinforced concrete by linear polarization method and electrochemical impedance spectroscopy (EIS) and analyzed various electrochemical parameters by partial least squares. Duprat et al [ 33 ] studied the statistical quantification of the Tafel coefficient of steel bars in concrete. Chang et al [ 34 ] evaluated the corrosion rate and Tafel parameters of three types of steel bars in concrete, new steel bars, and corroded steel bars in seawater.…”