Abstract
This paper focuses on the coupling between the microcracking and shrinkage in the secondary creep of concrete in bending under a high sustained load. Based on an interaction between the cracking and the diffusion of moisture, microcracks can drive the growth of a crack in concrete at high stress level. This effect has been modeled in a simplified poromechanical model in the framework of continuum damage mechanic. The proposed model has been implemented in a discrete lattice code which uses Voronoi discretization for the conduit elements and Delaunay triangulation for the dual mechanical elements. The model has been validated against recent experimental tests on creep of fiber reinforced concretes in bending.