Computed tomography (CT) Image-based analysis of concrete microstructure using virtual element method

The analysis of actual concrete microstructure is challenging because the microstructure has various length scales associated with small voids and various sizes of aggregate particles. To efficiently and effectively analyze complex microstructure like concrete, the image-based virtual element method (VEM) is presented. Concrete microstructure is reconstructed using the complementarity of X-ray and neutron computed tomography (CT) images with the morphological filtering. Based on the reconstructed microstructure, a VEM mesh is generated through integrating microstructural and homogeneous meshes. A microstructural mesh is directly obtained from the reconstructed microstructure, while a homogeneous mesh is employed to control the level of accuracy in the computational simulation. Then, the mesh refinement in the image-based VEM is easily performed through increasing the number of elements in a homogeneous mesh. Computational results converge to the reference solution of strain error under mesh refinement while capturing local stress and strain concentration.