Numerical solutions for chloride diffusions using stochastic inputs

  1. Enrico Zacchei 1
  2. Caio G. Nogueira 1
  1. 1 Universidade Estadual Paulista
    info

    Universidade Estadual Paulista

    São Paulo, Brasil

    ROR https://ror.org/00987cb86

Actas:
Proceedings 3rd International Conference on Recent Advances in Nonlinear Design Resilience and Rehabilitation of Structures
  1. Helena Barros (ed. lit.)
  2. Carla Ferreira (ed. lit.)
  3. José M. Adam (ed. lit.)
  4. Norb Delatte (ed. lit.)

ISBN: 9789892098371,  9789892098388

Año de publicación: 2019

Páginas: 293-301

Congreso: 3rd International Conference on Recent Advances in Nonlinear Design Resilience and Rehabilitation of Structures (16-18 October 2019, Coimbra)

Tipo: Aportación congreso

GOOGLE SCHOLAR

Resumen

Corrosion damage of reinforcement in concrete elements due to chloride attack is amajor problem for long term durability of Reinforced Concrete (RC) structures and, if unvalued,it can put the whole or part of the structural system at risk, including the environment andpeople’s lives. The diffusion of the chloride ions in RC structures varies in time (days, years)and space (two dimensions and three dimensions) and depends on many uncertain factors, suchas the composition of the concrete and its properties, temperature, aging and humidity.Moreover, each of these factors have a several uncertain intrinsic sub-factors that are difficultto be defined. In this work two aspects have been studied: the content of chloride ions inconcrete and the fluctuation of the diffusivity. The first aspect by using stochastic randomnessparameters helps to estimate the service life of the structure, whereas the second one callsattention to the fact that the real nature of the diffusion process is random. Numerical analyseshave been carried out. The governing equations were modified to account for the non-constantdiffusion coefficient in hardened cement paste under non-steady-state condition. This paper’saim is to develop a new probabilistic analysis. Results show that the expected time for corrosioninitiation is around of 40 years, whereas the more probability of failure is around 50 years.Finally, the fluctuation of the diffusivity in 2D/3D model is carried out showing a reduction ofthe chloride content.

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