Analytical and numerical approaches to modeling of reinforcement corrosion in concrete

abstract

English

Corrosion of reinforcing steel in concrete is one of the most influencing factors causing the degradation of reinforced concrete structures, conducting to cracking and spalling. The detrimental effect of corrosion is due to the fact that a rust product has a volume 2-6 times larger than the original steel Consequently, the rust products exert an expansive stress on the surrounding concrete whose tensile strength is usually low. This paper attempts at the application of an analytical and numerical approaches to simulation of concrete cracking due to corrosion of reinforcement. At first, a combination and detailed analysis of two analytical models proposed is presented. Four distinct phases of the corrosion process are identified and a detailed guide through the mathematical development is described. in the next, numerical computations obtained with nonlinear finite element code are presented. The model features the state-of-the-art in nonlinear fracture mechanics modelling and the heterogeneous structure of concrete is modeled via spatially varying parameters of the constitutive law. The crack growth in concrete induced by corrosion of steel reinforcement is modeled with the crack band model combined with a suitable damage law. Finally, the results of the analytical studies are compared to numerical computations obtained with the nonlinear finite element code and the paper concludes with a real-life numerical example.

Degradatiuon, reinforced concrete, corrosion, analytical and numerical modeling, random fields

MATESOVÁ, D.; VOŘECHOVSKÝ, M.

10. 9. 2007

Cape Town, South Africa

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