Aggregate shape effect on the diffusivity of mortar: A 3D numerical investigation by random packing models of ellipsoidal particles and of convex polyhedral particles

•We simulate mortar diffusivity from a digital mesostructure by a lattice approach.•Aggregate particles are modeled as oblate and prolate ellipsoids and polyhedrons.•Shape effect for oblate ellipsoids is most pronounced comparing to prolate ellipsoids and polyhedrons.

This paper investigates the influence of aggregate shape on the diffusivity of mortar in three dimensions by random packing models of ellipsoidal and convex polyhedral particles. From a digital mesostructure and by a lattice approach, the diffusivity of mortar can be predicted. Simulations are compared with experimental results from literature and are discussed for mono-sized and multi-sized particle packing with and without interfacial transition zones (ITZ). It was found that the shape of aggregate has a significant effect on the diffusivity of mortar, and for oblate ellipsoids, the shape effect is most pronounced comparing to prolate ellipsoids and polyhedrons.