Validation of the Mixture Theory Based Model for Sulfate Attack in Concrete

Author(s): Chethan Gouder and Saravanan U
Paper category: Proceedings
Book title: Proceeding of the 71st RILEM Annual Week & ICACMS 2017
Editor(s): Manu Santhanam, Ravindra Gettu, Radhakrishna G. Pillai, Sunitha K. Nayar
ISBN:978-2-35158-195-7, 978-2-35158-190-2 (Set)
e-ISBN: 978-2-35158-191-9
Publisher: RILEM Publications SARL
Publication year: 2017
Pages: 443-450
Total Pages: 8
Language : English

Abstract: Concrete is the most widely used material for construction. When concrete comes in contact with sulfate carrying agents it reacts with them. Due to this chemical reaction, the chemical composition of concrete changes. This change in the chemical composition is known to manifest through physical changes like expansion, loss of stiffness and strength, cracking, spalling or a combination of these, resulting in failure of the concrete structure. Moreover, these chemical and physical processes are interdependent. Therefore, modeling sulfate attack involves capturing the coupling between chemistry and mechanics. In this paper, a model for sulfate attack in concrete based on the mixture theory framework is validated. Mixture theory can phenomenologically capture the chemistry and mechanics of the problem with their interdependencies. The coupling between the chemistry and mechanics of the problem comes about naturally in mixture theory. The model is validated by formulating, initial boundary value problems corresponding to unsteady state radial diffusion in cylinders until the diffusing front reaches the centre, and the resulting nonlinear governing differential equations are solved numerically using a finite difference scheme. Model calibration is done by comparing the concentration profiles with the Fick’s solution for pure unsteady diffusion and expansion for unsteady diffusion and reaction of the specimen with that determined experimentally. Changes occurring in concentration profiles and expansion to alterations in initial boundary conditions are discussed.

Online publication :2017
Publication type :full_text
Public price (Euros) : 0.00