3D microstructure modeling of stone masonry walls

We currently study the complex 3D microstructure geometry of stone masonry walls as well as their properties when stones and mortar layers are explicitly identified. The ultimate goal is to reach a deeper understanding of the mechanical behavior of stone masonry walls using detailed 3D microstructures. This project shall give us more details about the in-plane, out-of-plane, and leaf-separation behaviors as well as the interaction among them. This study begins with the generation of realistic microstructures by designing a ‘virtual mason’ algorithm that is able to mimic real masonry building techniques and produce morphologically realistic walls. The current algorithm is able to generate a wide spectrum of stone masonry walls that spans from the rubble stone masonry walls to brick masonry walls that are commonly found around Europe.

The 3D microstructures can be used to generate both bidimensional (2D) and tridimensional representative volume elements (RVEs) that can be used for homogenization and multi-scale numerical techniques (as illustrated by the following figure). In this project, the microstructures will be exploited in modeling the mechanical behavior by means of the finite element method (FEM) combined with fracture and contact mechanics. Such numerical approaches need to be fed with extensive material parameters defining the constitutive laws and resemble real material properties of the stone-mortar composite. Currently, we are working on identifying the strength of the in-between interfaces between the stones and mortar layers by investigating the stones’ surface roughness using the complex-valued spherical harmonics basis as a priori to run full 3D and 2D models.

Illustration of microstructure generator for 3D stone masonry walls by Shaqfa & Beyer (2022).