Abstract: The method of ascertaining fully grown passive film formation on steel rebar embedded in concrete utilizes electrochemical impedance spectroscopy (EIS) to determine, in situ, the degree of passive film formation on steel rebar embedded in concrete. A length of steel rebar and a counter electrode are both embedded in a concrete slab. A reservoir is supported on an external face of the concrete slab and filled with an electrolytic solution. A reference electrode is then positioned in the electrolytic solution, and the length of steel rebar, the counter electrode and the reference electrode are electrically connected an EIS test instrument to perform electrochemical impedance spectroscopy. The quality of passive film formation on the length of steel rebar is determined based on comparison of the electrochemical impedance spectroscopy results with known passive film formation data.

Abstract: The method of ascertaining fully grown passive film formation on steel rebar embedded in concrete utilizes electrochemical impedance spectroscopy (EIS) to determine, in situ, the degree of passive film formation on steel rebar embedded in concrete. A length of steel rebar and a counter electrode are both embedded in a concrete slab. A reservoir is supported on an external face of the concrete slab and filled with an electrolytic solution. A reference electrode is then positioned in the electrolytic solution, and the length of steel rebar, the counter electrode and the reference electrode are electrically connected an EIS test instrument to perform electrochemical impedance spectroscopy. The quality of passive film formation on the length of steel rebar is determined based on comparison of the electrochemical impedance spectroscopy results with known passive film formation data.