Analysis of elastic properties of symmetrically laminated beams in bending

Formulae for the bending stiffness, the static moment and the bending and shear stresses in symmetrically laminated beams are proposed. These beams are made of m different materials arranged in a total number of n layers. Such structures are designated (m, n) laminates. The particular case of bi-material laminates is presented as an example, and it is shown that synergistic effects may occur for the beam stiffness. The occurrence of these effects depends on the number of layers, the volume fractions of the materials and their modulus ratio. Intimate mixture of the materials yields a simple rule-of-mixtures behaviour.