Research And Development Of Portbal Reinforcement Corrosion Rate Measuring Instrument

The corrosion and deterioration of reinforcement could directly affect the reliability and safety of project structures and large buildings. The evaluation of corrosion degree is the key factor to predict the durability and remaining service life of rebar structures. Quality control, maintenance and restoration of these structures require a rapid and nondestructive monitoring technique that could detect the corrosion condition at an early stage. Comparatively, on-site corrosion rate measurements are of great practical interest in controlling the effects of corrosion protection measures, predicting the residual life of a structure, and deciding when remedial measures have to be taken on a structure.The rebars'corrosion in concrete is an electrochemical process. Applying electrochemistry method to evaluate the corrosion of rebars has the advantages of rapid measurement, high sensitivity, continuous tracking, on-site assessment and nondestructive monitoring. It has been employed successfully to detect the corrosion state and rate of test samples in lab as well as monitor and detect the corrosion of steel in field recently.In the thesis, the development status, methods and characteristics of reinforcement corrosion measuring technique are researched. Relevant physical and chemical methods are discussed, characteristics and limitations of which are compared. By analyzing the theory of uniform polarization measurement and guard ring method based on linear polarization technique, the final measurement scheme of the instrument is determined. Measuring instrument's hardware structure and theory are introduced detailedly, as well as control programs accomplished with Assembly language and C coding. Through the parameters acquired by field simulative experiments, the veracity and reliability of measuring data are verified.During debugging, when parameters been set properly, the instrument's measurement data could indicate the corrosion degree of rebars in concrete, achieving the requirement generally. The designed instrument could be widely applied on many outdoor establishments such as architectures, bridges, road surfaces and so on.