MODELLINGS OF CHLORIDE ION TRANSPORT IN MORTARS CONSIDERING ELECTROKINETIC BEHAVIORS AT PORE WALLS

Author(s): Yuya Takahashi, Yogarajah Elakneswaran and Tetsuya Ishida
Book Title: RILEM International Symposium on Concrete Modelling - CONMOD 2014
Editor: Kefei Li, Peiyu Yan and Rongwei Yang
ISBN: 978-2-35158-139-1
e-ISBN: 978-2-35158-140-7
Publisher: RILEM Publications SARL
Publication year: 2015
Pages: 343-350
Total Pages: 8
Language: English

Abstract: This study aims to provide reasonable models which can simulate the chloride ion transport in cement hydrates which contain admixtures based on nm-scale phenomena. Focusing on the electrokinetic properties of pore walls, equations for thickness of adsorbed chloride layer, effective length of electric double layer and the size of transport unit of chloride ion are formulated and installed to the models in the thermodynamic analytical system, DuCOM. With the proposed transport model and existing pore structure model, different threshold radii for chloride movement due to different characters of hydrates can be calculated. Experimental results of salt water immersion test with mortar specimens are used for the verifications of the proposed model. Chloride ion profiles of mortars using blast furnace slag and/or fly ash are measured and compared with the analytical results. As a result, proposed model well simulate not only the shapes and penetration depths of only ordinary Portland cement cases, but also the shape of chloride ion profile under the usage of different admixtures.

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