A Micromechanical-Based Semi-Empirical Model for Predicting the Compressive Strength Degradation of Concrete under External Sulfate Attack

Abstract

As one of the most harmful ions in the environment, sulfate could cause the deformation and material deterioration of concrete structures. Models that accurately describe the whole chemo–transport–mechanical process of an external sulfate attack (ESA) require substantial computational work and contain complex parameters. This paper proposes a semi-empirical model based on micromechanical theory for predicting the compressive strength degradation of concrete under an ESA with basic properties of the undamaged material and limited computational effort. A simplified exponential function is developed for the total amount of the invading sulfate, and a second-order equation governs the chemical reaction. A micromechanical model is implemented to solve the mechanical response caused by an ESA. The model is able to describe the compressive stress–strain behavior of concrete subject to uniaxial loading in good agreement with the experimental results. For the case of a sulfate-attacked material, the relationship between compressive strength and expansion is calculated and validated by the test results. Finally, the deterioration process of compressive strength is predicted with the test results of deformation.

Visão sistêmica sobre publicações relacionadas aos modelos de previsão do ataque por sulfatos em matrizes cimentícias

“…Nota: 1 com adição de cinza volante; 2 pavimentos estabilizados com cimento Portland; 3 com adição de rejeitos de mina desidratados; 4 com fibras de PVA, cinza volante, agente de expansão e redutor de água; 5 concreto de junta longitudinal de túnel de metro; 6 concreto de revestimento com sílica ativa e cinza volante; e 7 concreto permeável. CHEN et al, 2021;FU et al, 2021;HAN;LI;CHEN, 2021;HOU et al, 2021;SONG et al, 2021;JU, 2021;GU et al, 2022;MELARA et al, 2022). As modelagens empíricas de ESA também foram obtidas com dados baseados em ataque por sulfato de sódio (ZHOU et al, 2015a;SAHOO;MAHAPATRA, 2018;MIN et al, 2019;LIAO et al, 2020;YAO;YANG;CHEN, 2020), e em alguns trabalhos o modelo é desenvolvido com base em dados tanto de sulfato de sódio como de magnésio, como é o caso de Ouyang (1989), Santhanam, Cohen e Olek (2002) e Lee et al (2015).…”