Imaginología por resonancia magnética y la determinación de cloruro y sodio en mortero de cemento Pórtland

Abstract

CORROSION OF THE REINFORCEMENT IS ONE OF THE MAIN CAUSES OF DETERIORATION OF CONCRET ESTRUCTURES. CHLORIDE PENETRATION INTO CONCRETE DUE TO EITHER DIFFUSION OR ABSORPTION IS AN IMPORTANT CONTRIBUTOR TO THE CORROSION OF EMBEDDED STEEL IN CONCRETE. IN NORTHERN COUNTRIES, DEICING SALTS ARE A MAJOR FACTOR IN THE DETERIORATION OF HIGH WAYS AND IN ALL COUNTRIES, CHLORIDES FROM SEA WATER EXACERBATE THE DETERIORATION PROCESS. IN ORDER TO ASSESS THE CHLORIDE PENETRATION, DESTRUCTIVE, LOW SPATIAL RESOLUTION AND TIME CONSUMING METHODS ARE ROUTINELY USED. THE SPRITE MAGNETIC RESONANCE IMAGING IS A NON DESTRUCTIVE TECHNIQUE THAT HAS DEMONSTRATED TO BE SUITABLE TO IMAGE MATERIALS POSSESSING SHORT LIFETIME SIGNALS IN CLUDING PÓRTLAND CEMENT BASED MATERIALS. THIS PAPER WILL DEMONSTRATE THE ABILITY OF SPRITE MRI TO DETERMINE THE DISTRIBUTION OF CHLORIDES IN MORTAR DURING NACL SOLUTION CAPILLARY ABSORPTION OR DIFFUSION. IN ADDITION, PRELIMINARY EXPERIMENTS INDICATE THAT THE TECHNIQUE CAN BE USED TO IMAGE THE DISTRIBUTION OF CHLORIDES IN CONCRETE/MORTAR CONTAINING NORMAL PORTLAND CEMENT, WHICH MAKES IT POSSIBLE TO STUDY THE PENETRATION OF CHLORIDES IN CORES TAKEN FROM FIELD CONCRETE.