Abstract:
This paper presents a methodology for the prediction of dam concrete instantaneous and long-term deformability properties using discrete element method (DEM) based on particle models (PM). The concrete mix, namely the content, size and distribution of the aggregates is explicitly taken into account. This type of concrete has large aggregate size and fraction volume. Due to the computational cost of the analysis of a large number of particles, dam concrete specimen is represented by an arrangement of mortar particles and of coarse aggregates particles. The overall behaviour is determined by the micro properties at each contact type, i.e., mortar-mortar, aggregate-aggregate, and aggregate-mortar which defines the interfacial transition zone (ITZ).
The proposed approach is to characterize and model both the mortar and the coarse aggregates separately and study their interaction in the heterogeneous model of concrete. For the mortar, a long-term analysis is required for modelling the aging viscoelastic properties. For the aggregates, an elastic analysis defines the contact micro properties in order to obtain the macro properties of the intact rock.
The numerical results obtained from the dam concrete particle model using DEM show a good agreement with the available experimental results for several loading ages.