An analytical model for the bio-inspired nacreous composites with interlocked “brick-and-mortar” structures

This paper establishes a closed-form analytical solution for the bio-inspired nacreous composites with interlocked “brick and mortar” (B-and-M) structure, with considering the influence of tension zones of the soft matrix, which was neglected in the classical tension-shear chain (TSC) model. It is found that vertical mortar layers have a significant effect on the mechanical properties of B-and-M structure in the state of plane strain. Parametric study shows that the deformation mechanism of the interlocked B-and-M structure is dependent on the length of vertical mortar layers and interlocking angle. On basis of this analytical solution, the influence of the interlocked structures on mechanical properties and deformation modes of nacreous composites is further evaluated, which shows that the mechanical properties of the nacreous composites can be optimized, with tuning of the length of the bricks and the interlocking angle. The results present a deep understanding of the deformation mechanisms of the bio-inspired nacreous composites with interlocked B-and-M structure and potentially provide guideline to the design and optimization of bio-inspired composites with high strength and high ductility.