chapter
8 Pages

Risk of stress corrosion cracking of prestressing steels in contact with galvanized components

J. Mietz, A. Burkert & J. Lehmann G. Eich

ABSTRACT: In order to clarify under which practical conditions real risks for hydrogeninduced stress corrosion cracking of prestressing steels in contact with galvanized constructional elements exist laboratory investigations in aqueous solutions and in concrete as well as tests with stressed prestressing steels were carried out. While different distances between steel and zinc (cathode and anode) showed only a negligible influence on the polarization of the steel a significant dependence on the area ratio steel/zinc was observed. A critical area ratio of 10:1 can be defined above which polarization of the steel to hydrogen evolution potentials is unlikely. The results obtained in the laboratory concerning the critical area ratio were confirmed by on-site investigations in a precasting plant.