Lattice Discrete Particle Modeling for coupled concrete creep and shrinkage using Solidification Microprestress Theory

The macroscopic continuum creep simulation always neglect internal creep/relaxation at lower scales due to the internal self-equilibrated stresses. So far, a comprehensive model for concrete creep at the meso-scale level has been lacking. In this paper, such a shortcoming is over come by the explicit implementation of the solidification-microprestress (SM) theory within the Lattice Discrete Particle Model (LDPM). Aging effect is obtained using a global reaction degree of concrete obtained by a multi physics model evolving temperature, humidity and cement degree of reaction in full coupling over time and space leading to an elegant and simple implementation within the LDPM framework through an imposed eigenstrain. This leaves the features of the LDPM constitutive equation simulating material strength and toughness completely unaltered. To show the superiority of the proposed model, extensive calibration and validation of the model is pursued by numerical simulations of experimental data from literature.