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Corrosion Induced Cracking: Analytical and Non-Linear Fracture mechanics Modelling. OSTRAVA 10-02-2005 Institute of Structural Mechanics Faculty of Civil Engineering University of Technology, Brno Florentina Pernica, Drahomír Novák. Introduction.
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Corrosion Induced Cracking: Analytical and Non-Linear Fracture mechanics Modelling OSTRAVA 10-02-2005 Institute of Structural Mechanics Faculty of Civil Engineering University of Technology, Brno Florentina Pernica, Drahomír Novák
Introduction • The aim:to develop NLFM computational model for the corrosion induced cracking and compare the results with one obtained from analytical model. • Analytical model for corrosion induced cracking in RC structures. • Computational model that was prepared using software ATENA 2D.
Analytical model for corrosion • The deterioration mechanism: corrosion of reinforcement. • Two processes may lead to depassivation of steel: • - carbonatio of concrete • - chloride ingress. • An analytical model for corrosion induced cracking in RC structures has been derived based on the concepts of fracture mechanics and smeared cracks.
The computational model • Was done using software ATENA 2D based on non-linear fracture mechanics. • Was developed mainly for the realistic simulation of RC structures, realistic modelling of cracking in quasi-brittle materials. • The corrosion problem was solved as 2D plane stain.
Concrete E (Gpa) ft (MPa) fc (MPa) Gf (MN/m) 3D NonLinCementitious 2 3.032E+04 2.3 -23 4E-05 Alternative 1 Modelling of the entire concrete circle: mesh, boundaries conditions and applying shrinkage Evolution of cracks at peak load
Concrete E (Gpa) ft (MPa) fc (MPa) Gf (MN/m) 3D NonLinCementitious 2 3.032E+04 2.3 -23 4E-05 Alternative 2 2 1 Quarter of concrete circle 1- the values of stress were taken 2-the values of crack width were measured Graphs stress vs. crack width
Concrete E (Gpa) ft (MPa) fc (MPa) Gf (MN/m) 3D NonLinCementitious 2 3.032E+04 2.3 -23 4E-05 3D NonLinCementitious 2 weaker 2.5E+04 1.8 -18 1.5e-05 Alternative 3 1 Evolution of cracks in first steps Evolution of cracks at peak load
Conclusions • FEM computational model was developed. • The trends of stress vs. crack width curves of both experimental and numerical results were similar. • The differences:due to insufficient previous material parameters calibration and due to comparing linear with non-linear solution.