LONG-TERM EVAlLUATION OF EFFECTIVENESS AND DURABILITY OF CATHODIC PROTECTION SYSTEMS APPLIED TO RAILWAY PC GIRDER

Abstract

 The long-term effectiveness and durability of five different electrolytic corrosion protection systems aplied to railway prestressed concrete girders were investigated after 20 years of application. The evolution of the electric potential and of the depolarization value over time were monitored, and the results indicated that all of these methods continued to be effective in preventing corrosion. However, the improvement in corrosion environment around the internal steel was found to be different for each method. Additionally, areal distrib tion of the depolarization value were studied. In the case of the titanium grid method, the results are widely scattered, and even standard depolarization value was not fulfilled in some areas. Since, it was found that the titanium spraying method causes delamination of the anode material coating, this effect was evaluated and its cause was discussed.