Abstract
Computational investigation on composite materials like concrete is challenging because of complex and uncertain microstructure characteristics. For example, the compositions, sizes, shapes, and arrangements of the various phases of distinct properties, present in concrete, constitute its microstructure. To accurately reconstruct concrete microstructure, the complementarity of X-ray and neutron computed tomography images is employed. Void, aggregate, and cement paste phases are successfully captured down to the images’ spatial resolution, even though the aggregate consists of multiple minerals. The reconstructed complex microstructure is efficiently and effectively analyzed using the virtual element method (VEM) although the microstructure has various length scales associated with small voids and various sizes of aggregate particles. Furthermore, the interfacial fracture energy between aggregate particles and cement mortar is firstly measured using three-point bending tests. The measured interfacial fracture energy was about 7 ~ 10% of the mortar fracture energy in this study while being validated by predicting crack pattern and load-displacement relations with cohesive zone modeling, which accounts for crack branching and coalescence.
Bio
Kyoungsoo Park is a Professor in the Department of Civil & Environmental Engineering at Yonsei University (Korea). Dr. Park’s educational background includes a B.S. Degree in Civil Engineering from Hanyang University in Seoul, Republic of Korea, and a M.S. and Ph.D. degrees in Civil Engineering from The University of Illinois at Urbana-Champaign with emphasis in cohesive fracture models for the fracture analysis of quasi-brittle materials. He joined the School of Civil and Environmental Engineering at Yonsei University in 2011, worked as an Assistant Professor, and has been a professor since 2022. Professor Park focuses on computational and experimental mechanics to investigate nonlinear material failure behavior in relation with material microstructure. For instance, he studies concrete microstructure reconstruction using computed tomography images while developing computational methods associated with cohesive zone modeling, virtual element methods, and stress recovery. He has been an editor of the International Journal of Concrete Structures and Materials since 2015, an associate editor of the Journal of Civil Engineering (KSCE) since 2013.
