A peridynamic approach to sulfate attack chemistry in cementitious materials: a 1D diffusion–reaction model with multiple species

The chemical–physical deterioration process referred to as sulfate attack can affect the cementitious materials, typically inside massive structures, over decades of their service life. Due to the difficulties in coupling chemistry and materials mechanics, exacerbated by the lack of experimental data, the mathematical modeling of the sulfate attack represents a challenging topic. In this paper, a one-dimensional (1D) diffusion–reaction model, based on a peridynamic approach, is proposed to simulate this deterioration process exclusively from the chemical point of view, emphasizing the interactions between two aluminate phases and the sulfate ions. Parametric analyses are carried out to assess the effect on this process of the sulfate concentration at the boundary, of the aluminate concentration within the sample, of the reaction rate constants depending on the temperature and on the activation energy. Peridynamic simulations, carried out in a MATLAB® platform, have been critically compared to the available theoretical solution and to the finite element predictions provided by COMSOL Multiphysics®. The numerical results obtained in the present 1D scenario confirm the capability of the proposed model to describe the sulfate attack as a diffusion–reaction problem with multiple species, which is of crucial interest to improve the engineering design of new concrete infrastructures and to plan the maintenance interventions for the existing ones.