Electrochemical process for adjusting the steel-to-concrete bond strength and improving the sealing of the steel-concrete interface

摘要

If source of DC voltage, preferably in the range of 5 - 40 volts, is connected at its negative side to the embedded steel and at its positive side to an external distributed electrode formed on the surface of the concrete structure, (eg. a self-adherent electrolytic mass of moist pulp fiber, or a conductive coating), application of voltage to the structure and the resulting current flow between embedded steel and the external electrode initially results in a progressive reduction in the steel-to-concrete bond strength (useful in connection with pre-tensioned or post-tensioned structures) and continued application of the voltage results in a progressive increase in bond strength, ultimately reaching a maximum strength significantly above initial values. By reference to pre-established database values, the process may be easily controlled to realize targeted modifications in bond strength. Significant improvement can also be achieved in the sealing of the interface between steel and concrete, to prevent seepage of contaminating liquids or gases along the interface.