RESISTANCE OF CONCRETE TO FROST AND DEICING SALT

FROST- UND TAUSALZBESTAENDIGKEIT VON BETON

THE AIM IS TO OBTAIN MORE IN-DEPTH KNOWLEDGE OF THE REAL FACTORS WHICH CAUSE DAMAGE WHEN FROST AND DEICING SALTS ACT ON CONCRETE. THE EMPHASIS IS ON THE DESCRIPTION OF THE STRUCTURE OF THE CONCRETE, PARTICULARLY WITH RESPECT TO INDIVIDUAL STRUCTURE CONSTITUENTS (AGGREGATES, CEMENT PASTE, AIR VOIDS, CRACKS, OTHER STRUCTURAL DEFECTS ETC), AND WITH RESPECT TO THEIR MUTUAL ORIENTATION, BONDING ETC. THESE PROPERTIES OF THE CONCRETE ARE TO BE EXAMINED IN PARTICULAR IN RELATION TO DISTANCE FROM THE SURFACE OF THE CONCRETE AND TO TYPE OF CONCRETE MANUFACTURE. BY MEANS OF AN IMAGE DATA ANALYSER (QUANTIMET) STEREOLOGICAL MEASUREMENTS CAN ALSO BE CARRIED OUT, SUCH AS FOR EXAMPLE DETERMINATION OF VOIDS DISTRIBUTION OR CRACK ORIENTATION. THE STUDIES ARE BEING CARRIED OUT IN CLOSE COOPERATION WITH EMPA (SWISS FEDERAL MATERIALS TESTING INSTITUTE) IN DUEBENDORF AND WITH THE CEMENT INDUSTRY.