PSI - Issue 79

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ScienceDirect

Procedia Structural Integrity 79 (2026) 259–265

© 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of IGF28 - MedFract3 organizers Abstract Concrete has an intricate internal structure exhibiting non-linear postpeak softening and quasibrittle fracture behavior. To accurately capture its mechanical and failure behavior, it is imperative to understand the interaction between major constituting phases of concrete. In this study, the effect of aggregate shape and volume fraction on mesoscale fracture of geometrically similar beams have been investigated. A two-dimensional mesoscale model consisting of mortar, aggregate and interfacial transition zone has been modelled using cohesive elements in finite element method. The models are subjected to three-point bending and the fracture behavior is governed by damage-based constitutive laws. A rigorous fracture characterization has been conducted for different aggregate packing percentages with circular, elliptical and polyhedron geometries. The findings highlight the role of mesoscale modelling for predicting the mechanical and fracture behavior in concrete mixes. 28th International Conference on Fracture and Structural Integrity - 3rd Mediterranean Conference on Fracture and Structural Integrity Effect of aggregate shape and volume on concrete fracture: A mesoscale modelling Mansi Gupta a , Sonali Bhowmik a * a National Institute of Technology Rourkela, India 1. Introduction Concrete is the commonly used construction material in infrastructures through the world. Albeit its extensive uses in construction, the cracking in concrete is most common problem which leads to ultimate failure under the action of loading (Zhu et al. (2024)). The concrete has a complex hierarchical structure, owing to its multiscale and multiphase structural properties that are difficult to analyze. For a thorough and precise understanding of structural performance of concrete, it is imperative to understand the fracture mechanisms happening at constituent phases. The fracture study of concrete initiated with the advent of linear elastic fracture mechanics (LEFM) and has attracted significant attention since then (Kaplan (1961)). However, the size effect behavior and the existence of fracture process zone (FPZ) shows that LEFM is unable to accurately capture the non-linearity in concrete (Kesler et al. (1972)). To address this limitation, the non-linear fracture mechanics has been greatly explored over the past decad es (Bažant and Oh (1983)). Despite the advances in fracture studies, the concrete fracture is itself an intricate process comprising of various toughening mechanisms such as crack branching, aggregate interlocking, crack bridging and coalescence (Bažant et al. (1998)). The experimental a nd numerical investigations in concrete fracture also hints at the role of concrete’s internal structure on the overall macroscopic properties. The aggregate shape, size, and roughness can Keywords: Concrete; Fracture; Mesoscale Modelling; Aggregate; Interfacial Transition Zone

* Corresponding author. bhowmiksonali@nitrkl.ac.in .

2452-3216 © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of IGF28 - MedFract3 organizers 10.1016/j.prostr.2025.12.332