Alternative methodology to consider damage and expansions in external sulfate attack modeling

• Published in: Cement and concrete research 2014-09, Vol.63, p.105-116
• Main Authors: Ikumi, Tai, Cavalaro, Sergio H.P., Segura, Ignacio, Aguado, Antonio
• Format: Article
• Language: English
• Subjects: Applied sciences; Building failures (cracks, physical changes, etc.); Buildings; Buildings. Public works; Concrete; Concrete (E); Concretes; Concretes. Mortars. Grouts; Construcció; Diffusion; Durability; Durability (C); Durability of constructions; Durability. Pathology. Repairing. Maintenance; Edificació; Estructures; Exact sciences and technology; General (composition, classification, performance, standards, patents, etc.); Materials; Materials de construcció; Materials metàl·lics de construcció; Mathematical models; Methodology; Modeling; Modeling (E); Pore size; Pore size distribution; Pore size distribution (B); Porosity; Strain; Strength of materials (elasticity, plasticity, buckling, etc.); Structural analysis. Stresses; Structures; Sulfate attack; Sulfate attack (C); Sulfates; Àrees temàtiques de la UPC
• ISSN: 0008-8846; 1873-3948
• DOI: 10.1016/j.cemconres.2014.05.011

A diffusion–reaction numerical model is proposed to simulate the response of concrete exposed to external sulfate attack. Diffusion properties are modified based on the strain reached and the ratio of porosity filled by ettringite. A direct and intuitive approach is proposed for the consideration of the diffusion in a cracked porous media based on the constitutive law of the material. A methodology to compute expansions based on a more realistic consideration of the concrete porosimetry is presented, by which it is possible to distinguish different strain contributions from different pore sizes. The described approach also allows the consideration of different capacities to accommodate expansive product for each pore size considered and the faster filling rate existent in small pores. Critical parameters of the numerical model developed are recognized and established. Expansions obtained by the new model are in good agreement with experimental data published in the literature.