Study of a different carbonation intensity on the internal surface of cracks and inside concretes with dense aggregate and concrete recyclate

The paper focuses on the experimental physical - chemical analysis of different carbonation intensity by TG/DTG and FTIR method on the selected surfaces of concretes with aggregate and with concrete recyclate, with and without polymer and steel fibres. By means of thermal analysis and infrared spectrometry, carbonation intensity from the specific amount of calcium carbonate and portlandite was tested on specimens scratched from the internal surface of cracks and on specimens from the inside of concrete. It seems that bending macrocraks do not significantly accelerate the process of carbonation in the depth of concrete. But they bring various corrosion agents to concrete. As regards the evaluation of carbonation intensity of different concrete samples, fibre concretes with concrete recyclate are more suitable for structural purposes than fibre concretes with dense aggregate. (paper)