Abstract
A new method based on the boundary element inverse analysis was developed to improve the accuracy and efficiency of AC impedance method for monitoring corrosion of a rebar in a concrete structure. In this method, the potential in the concrete domain is described with the Laplace's equation, the validity of which was verified experimentally by using a concrete block specimen. The potential in the concrete domain is calculated by solving the Laplace's equation using the boundary element method, and an inverse analysis is carried out to estimate the location and the complex impedance of the corroded part on the surface of a rebar from a small number of potential data measured on the surface of a concrete structure. The cost function to be minimized in the inverse analysis is a function of the difference between the measured and calculated values of potential. An example using a prismatic concrete block with an embedded piece of rebar was presented to demonstrate the accuracy and efficiency of the proposed method.
