Tough, Ductile, and Strong Hard-Soft Cementitious Composite Enabled by Multi-Material Additive Manufacturing.
Aimane Najmeddine1, Shashank Gupta1, William Makinen1
1Department of Civil and Environmental Engineering, Princeton University, NJ, USA.
Advanced Materials (Deerfield Beach, Fla.)
|April 10, 2026
Summary
This study introduces a novel multi-material additive manufacturing (MMAM) technique to create tough, ductile architected cementitious composites (ACC). These novel materials demonstrate significantly enhanced fracture resistance and ductility compared to traditional monolithic cementitious materials.
Area of Science:
- Materials Science and Engineering
- Additive Manufacturing
- Composite Materials
Background:
- Monolithic cementitious materials are inherently brittle and lack fracture resistance.
- Current additive manufacturing for cement-based materials is limited to single constituents.
- Architected designs offer potential but require multi-material approaches for enhanced properties.
Purpose of the Study:
- To develop a novel multi-material additive manufacturing (MMAM) technique for creating tough and ductile architected cementitious composites (ACC).
- To investigate the mechanical performance of layered hard-soft architected cement-based composites inspired by natural structures.
- To establish a coupled experimental-numerical design approach for optimizing ACC properties.
Main Methods:
- Utilized a novel multi-material additive manufacturing (MMAM) technique to create layered hard-soft composites (mortar with silicone or polyurethane).
- Employed a coupled large-deformation phase-field-cohesive-zone (PF-CZM) framework for numerical simulations.
- Conducted experimental fracture analyses using digital image correlation (DIC) and acoustic emission (AE).
Main Results:
- Layered mortar-silicone composites showed 3.9- and 8.8-fold increases in fracture toughness and 11.7- to 12.4-fold increases in ductility compared to monolithic mortars.
- Numerical simulations predicted significant improvements in work-of-fracture with optimized soft-layer thickness and stiffness.
- Mortar-polyurethane composites achieved 82- to 187-fold higher fracture toughness and 22.6-fold higher ductility, with comparable flexural strength to monolithic mortar.
Conclusions:
- The proposed MMAM technique and layered hard-soft architecture enable the creation of damage-resilient architected cementitious composites.
- Synergistic mechanisms including crack arrest, bridging, and re-nucleation contribute to the enhanced mechanical performance.
- This fabrication-design-mechanics approach opens new avenues for next-generation resilient and multi-functional concrete structures.
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