EVALUATION OF EXISTING AND FUTURE REPORTS ON THE DEMOLITION OF PRESTRESSED CONCRETE STRUCTURES WITH REFERENCE TO THE LONG TERM BEHAVIOUR OF PRESTRESSING STEELS

AUSWERTUNG VON VORHANDENEN UND ZUKUENFTIGEN BERICHTEN UEBER ABBRUCHARBEITEN VON SPANNBETONBAUWERKEN IM HINBLICK AUF DAS LANGZEITVERHALTEN VON SPANNSTAEHLEN

A COLLECTION AND SYSTEMATIC EVALUATION IS TO BE MADE OF THE RESULTS OF STUDIES ON PRESTRESSING STEELS WHICH HAVE BEEN MADE DURING DEMOLITION OF PRESTRESSED CONCRETE STRUCTURES. THE RESEARCH IS IN TWO SECTIONS: (A) TO COLLECT THE STUDY REPORTS CONTACT HAS TO BE MADE WITH THE FEDERAL MINISTRY OF TRANSPORT, THE FEDERAL ROAD RESEARCH INSTITUTE, THE STATE MINISTRIES OF TRANSPORT AND THE APPROPRIATE ROAD AUTHORITIES. (B) THE EVALUATION AND PREPARATION OF THE INFORMATION OBTAINED IS TO BE CLASSIFIED AS FOLLOWS: PRESTRESSING STEEL - DEGREE OF CORROSION, STATIC AND DYNAMIC COEFFICIENTS, RESIDUAL STRESSING, FAILURE; INJECTION MORTAR - POROSITY, MOISTURE CONTENT, CONTENT OF CORROSION-PROMOTING IONS; SLEEVE - DEGREE OF CORROSION, MATERIAL; SURROUNDING CONCRETE - AGE AND STRUCTURE. IN THE EVALUATION THE REASONS FOR ANY DEMOLITION ARE TO BE INCLUDED TOGETHER WITH DETAILS OF PARTICULAR STRESSES ON THE STRUCTURE DURING ITS LIFE.