THE INFLUENCE OF CARBONATION ON DEICER SCALING RESISTANCE OF BLAST FURNACE SLAG CONCRETE (BFSC)

Author(s): Egüez, H. E., De Belie, N. and De Schutter, G.
Paper category: Conference
Book title: XIII International Conference on Durability of Building Materials and Components - XIII DBMC
Editor(s): Marco Quattrone, Vanderley M. John
Print ISBN: none
e-ISBN: 978-2-35158-149-0
Publication year: 2015
Pages: 126-133
Total Pages: 8
Language: English

Abstract: Blends of BFS/OPC concretes with slag binder ratios (s/b = 0, 0.5, 0.7) were initially wet cured and stored for 7 days at 20˚C and RH > 95%, followed by 21 days dry storage at 20oC and 65% relative humidity. Afterwards, several samples were exposed to accelerated carbonation under 10% CO2 and 60% R.H. while others were kept in laboratory controlled condition and natural CO2 exposure. Carbonated concretes were exposed to freeze and thaw cycles under deicing salt according to CEN/TS 12390-9 standard. Samples were analysed utilizing optical and scanning electron microscopy to determine the structure left after carbonation and associate its influence in concrete‟s de-icing resistance. The carbonation front was determined by spraying phenolphthalein on a freshly split surface. Open porosity of samples were determined after drying at 40oC and 105oC according to NBN B05-201. Optical microscopy shows an irregular arrangement of tiny bright calcium carbonate minerals spread in the concrete paste for the BFS concrete. This pattern was also observed by SEM, a technique which shows more details of what is believed to be a porous leached paste zone co-existing next to a calcium salt enriched deposition sector. OPC concrete remains insensitive to carbonation maintaining the same scaling resistance with time, while carbonation in the blended concretes increases and scaling resistance decreases with higher BFS content.

Online publication: 2015
Publication Type: full_text
Public price (Euros): 0.00