• Citer

3D mesoscale modeling of fracture in ultra-high performance cementitious composites: Unraveling the critical roles of fine aggregates, air voids and binder matrix

par Zhang, Bin Jia;Ehab Moustafa Kamel, Karim ;Massart, Thierry Jacques ;Snoeck, Didier ;Wang, Jianyun;Gao, Yun
Référence Engineering fracture mechanics, 345, 112445
Publication Publié, 2026-07-17

Article révisé par les pairs

• Accès en ligne
• Détails
• Contenu
• Statistiques

Résumé :

The fracture mechanism of ultra-high performance cementitious composites (UHPCCs) is rooted in their material heterogeneity associated with fine aggregates, air voids, and binder matrix. Herein, a 3D mesoscale modeling framework is developed to investigate the full fracture process of UHPCCs under uniaxial tension. This framework integrates an efficient representative volume element (RVE) generation algorithm, a representation method for binder matrix variability, and an advanced fracture simulation approach. Specifically, the level-set random sequential addition (LS-RSA) scheme is extended to construct 3D RVEs with realistic configurations of fine aggregates and air voids. The spatial variability of the binder matrix is explicitly incorporated using an X-ray computed tomography (XCT)-derived Gaussian random field. Phase-field fracture simulation is then implemented to reproduce the tensile fracture process. The results demonstrate that the predicted elastic modulus and tensile strength agree well with the tested values, with errors within 7%. Fine aggregates mainly regulate crack propagation by deflecting cracks and increasing crack tortuosity, whereas air voids act as dominant geometric defects controlling crack initiation. Increasing fine aggregate size reduces tensile strength by promoting earlier cracking, but moderates post-peak softening through increased crack tortuosity. Eliminating air voids increases tensile strength but causes more brittle failure due to suppressed pre-peak cracking and abrupt elastic energy release. Binder matrix variability is essential for realistic crack evolution. Neglecting this variability overestimates tensile strength and suppresses preferential pre-peak crack growth, while increasing its correlation length enhances weak-zone connectivity and promotes more gradual post-peak softening.