Rebar corrosion monitoring using novel embedded filament mini-sensors

摘要

The prediction and assessment of corrosion initiation at reinforcement is a key consideration in evaluating the service life of corroded concrete structures.This paper deals with the development,testing and use of novel calibration-free mini-sensors for the evaluation of rebar corrosion initiation in concrete members.By such “watch dog”-sensors,consisting of several parallel arranged,0.065 to 0.5 mm thin iron filaments,the penetration of the depassivation front into concrete can be monitored depth-dependently.Main advantages of the filament-sensors are the simple design and measuring principle.Also a subsequent sensor installation into boreholes with a filling grout is viable.Several series of lab investigations in corrosive solutions and at small concrete members as well as first practical tests on concrete members using filament-sensors were conducted.Here,starting with the state-of-theart-review of corrosion monitoring,the results and the experience made with the types of embedded sensors are presented and briefly discussed.