Modelling of three-dimensional crack patterns in deep reinforced concrete structures

• We study numerically the cracks appearing in reinforced concrete structures.
• A continuum damage mechanics-based model is used at the global scale.
• A discrete model is used at the local scale.
• The modelling of rebars at the local scale is discussed.
• A predictive and quantitative 3D description of the crack pattern is obtained.

The analysis of the crack width variation within the depth of a reinforced concrete structure is difficult to perform. No experimental measurement can give a non-intrusive, three-dimensional and quantitative description of cracking. Moreover, most of the design codes cannot give a predictive measurement of the full cracking pattern. This paper applies a global/local computational strategy in order to quantify the cracking behaviour of reinforced concrete structures. A continuous damage model is used to perform a full resolution at the global scale. Then a reanalysis of the damaged zones is performed at the local scale with a discrete element model. This strategy has proved its efficiency for the study of cracking of small laboratory specimens made in concrete. The extension to massive reinforced structures is achieved here and numerical results on the influence of three-dimensional effects and rebars on cracking are given.