Computationally efficient, discrete mechanical models of grid-reinforced cement-based composites

Thin-walled structures made of concrete, or other forms of cement-based composites, are common within the civil infrastructure.In many situations, such structures experience out-of-plane loading, which can lead to various forms of distributed cracking depending on the boundary conditions.Discrete mechanical models are appropriate for simulating such cases of distributed fracture.However, their applications toward modeling the out-of-plane behavior of thin-walled structures are few.One main difficulty involves the large computational expense associated with three-dimensional discretizations of the structure, which are typically needed to capture crack propagation through the wall thickness.In this research, an extension of the Voronoi-cell lattice model (VCLM) is proposed to simulate the behavior of planar structural elements subjected to out-of-plane loading.Based on a two-dimensional network of nodes, a layered assembly of the element cross-sections provides a three-dimensional description of section behavior.With sufficiently fine discretization of the planar structure, this layered VCLM is shown to be elastically uniform for combined membrane and flexural loadings.Compared to corresponding three-dimensional discretizations, computational expense is greatly reduced, thus extending the range of modeling applications.Other capabilities of the layered VCLM, and the consequences of mesh resolution of the lattice structures, are demonstrated through elastic stress analysis and fracture analyses of grid-reinforced cement-based composites.