POSSIBILITIES AND LIMITS OF THE USE OF NON-DESTRUCTIVE TEST PROCEDURES FOR CHECKING EXISTING CONCRETE STRUCTURES

MOEGLICHKEITEN UND GRENZEN DER ANWENDUNG ZERSTOERUNGSFREIER PRUEFVERFAHREN FUER DIE UEBERPRUEFUNG BESTEHENDER BAUWERKE AUS BETON

THE AIM OF THE WORK IS TO ESTABLISH THE POSSIBILITIES AND LIMITS OF USING NON-DESTRUCTIVE METHODS FOR UNDERTAKING SURVEILLANCE OF ENGINEERING STRUCTURES; THIS IS TO BE DONE BY MEANS OF A WORLD-WIDE STUDY OF THE LITERATURE AND QUESTIONS PUT TO RELEVANT INSTITUTES. SINCE IMPORTANT INFORMATION IS NOT PUBLISHED, THE SECOND PART OF THE WORK IS TO CONSIST OF VISITS TO ALL THOSE RESEARCH INSTITUTES AND SURVEILLANCE AUTHORITIES WHICH HAVE HAD PRACTICAL EXPERIENCE WITH A PROCEDURE WHICH SEEMS SUITABLE OR WHICH COULD BE FURTHER DEVELOPED. THE STUDY IS TO BE LIMITED TO METHODS WHICH CAN BE USED WITHOUT SPECIAL EQUIPMENT HAVING TO BE INCORPORATED INTO THE STRUCTURE AND WHICH ARE REASONABLY CHEAP. OF PARTICULAR INTEREST ARE THOSE METHODS BASED ON THE INTRODUCTION OF MECHANICAL OR ELECTROMECHANICAL VIBRATIONS AND MEASUREMENTS OF TIME, FREQUENCY OR DAMPING (OSCILLATION ANALYSIS, ULTRASONIC METHODS, MICROWAVE METHODS, HIGH-FREQUENCY CONDUCTIVITY, INDUCTION METHODS, X-RAYS, INFRARED METHODS ETC).