Influences of the Reinforcement and Surface Layers on the Apparent Concrete Resistivity by Using a Four-Electrode-Probe

摘要

Concrete resistivity is a significant parameter to evaluate the durability of reinforced concrete structures. It can be determined non-destructively by using a four-electrode setup. However reinforcement bars as well as layers with different resistivities have a significant influence on the readings. In the case of a four-electrode measurement the apparent resistivity is commonly determined on the base of a semi-spherical distribution of the current in the concrete which does not fully reflect the real situation. For surface layers a cylindrical approach is presented to describe this phenomenon analytically. The influences of reinforcement bars are more complex to specify. Fundamental investigations are made experimentally in solution and by numerical simulations.