Modelling of reinforced concrete with the discrete element method
The goal of the research project is to develop a discrete element model for reinforced concrete, which describes the bearing behaviour of reinforced concrete and the characteristic crack formation.
For the economic use of reinforced concrete structural components, the occurrence of cracks in the concrete is unavoidable, since the reinforcement only absorbs the tensile forces assigned to it after crack formation. However, depending on the crack width and type, these cracks can reduce the corrosion protection of the reinforcement and thus the lifetime of the reinforced concrete structural component. The crack pattern that occurs depends on many parameters, such as loads, arrangement of the reinforcement, concrete properties and the bond between the concrete and the reinforcement. The latter is also influenced by the processing of the concrete.
With the discrete element method it is possible to describe the bearing behaviour of reinforced concrete and the formation of cracks for different forms of the parameters mentioned above and to simulate the occurring cracks. With the completed and ongoing research projects within the Graduiertenkolleg 2075 of Mr. Ockelmann and Mr. Flack, a model for the description of concrete is already available. The concrete is composed of solid particles which are understood as aggregates. These particles are connected by spring-damper systems and a fracture condition, which are adapted to the macroscopic behaviour of the concrete. This model has to be extended with regard to the application for reinforced concrete. Furthermore, a model for the description of the reinforcement and the bond behaviour has to be developed. Starting from the mechanical model, it is possible to add different transport processes.
Additional literature :
F. Ockelmann. Modellierung und numerische Analyse von Beton sowie faserverstärktem Ultrahochleistungsbeton mit der Diskrete Elemente Methode. Diss. 2018.
C. Flack and D. Dinkler. Mehrfeldmodellierung von Beton mit der Diskrete Elemente Methode. In: Schneider J., Kiziltoprak N. (eds) Forschungskolloquium 2018 Grasellenbach. Springer Vieweg, Wiesbaden, 2018.