Asia's economic growth has prompted development of the market---composite material, whose value has surpassed 18 billion Euros, with average annual growth rate 8% year by year. Moreover, aerospace and wind energy market develop at double-digit speed. Therefore, composite material has made a better life for us. Composite material is made from two or more materials with different nature, which mainly composed of reinforced materials and basic materials. Not only have they maintained the merits of reinforced and basic materials, but also they have excellent performance by complementation and connection of these parts. With the features of great strength, high stiffness, good anti-fatigue property, anisotropy and design ability of material property, composite materials access to significant weight-loss benefits and improve structure and properties in aerospace. Design of composite materials co-structure is design for ply number of layers, ply thickness and ply angle. Composite materials excellent performance could not put into full play just adopted by replacement design (constant stiffness, constant strength), quazi-network design and so on. In analysis of composite structure, finite element numerical simulation analysis has been widely used, whose basic principle is the same as isotropic materials in nature except for discrete methods and constitutive matrix. Discretization in composite finite element method is twofold, which includes discretization of structure and each layer, and this method can make mechanical properties of ply, ply orientation and ply form reflected directly into stiffness matrix. Making every layer as a unit, finite element analysis software compounds enhanced materials and body together, discussing structure of macroscopic mechanical behavior. Therefore, micro-mechanical behavior led by composite multi-dimensionality can be neglected.
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