摘要：Mimicking the natural design motifs of structural biological materials is a promising approach to achieve a unique combination of strength and toughness for engineering *** this study,we proposed a 2D computational model,which is a two-hierarchy hybrid composite inspired by the ultrastructural features of *** model is composed of alternating parallel array of two subunits(A&B)mimicking‘mineralized collagen fibril’and‘extrafibrillar matrix’of bone at ultrastructural *** subunit-A is formed by short stiff platelets embedded within a soft *** subunit-B consists of randomly distributed stiff grains bonded by a thin layer of tough adhesive *** assess the performance of the bioinspired design,a conventional unidirectional long-fiber composite made with the same amount of hard and soft phases was *** finite element simulation results indicated that the toughness,strength and elastic modulus of the bioinspired composite was 312%,83%,and 55%of that of the conventional composite,*** toughness improvement was attributed to the prevalent energy-dissipating damage of adhesive phase in subunit-B and crack-bridging by subunit-A,the two major toughening mechanisms in the *** study exemplifies some insights into natural design of materials to gain better material performance.