EXPLICIT FORMULAS FOR ELASTIC MODULI AND STIFFNESS MATRICES OF THE COMPOSITE LATTICED PLATES

In this paper a new approach is presented to identify the stiffness matrices and elastic moduli of composite latticed plates versus angle of helical ribs and other geometrical variables. This approach introduces explicit equations in order to compute the moduli of elasticity and Poisson’s ratio of 3-ribbed latticed plates. By computing the stiffness matrix of composite latticed plates, [A], [B] and [D] matrices are easily computable for a laminate which comprises these latticed plates. Also using the stiffness matrix of these plates, their elastic moduli are attained as the functions of structural variables. The three models were realized in a computer code using symbolic computation. Numeric verification of the mathematical models is performed with a finite element analysis package. Finally, the variations of the elastic moduli of a composite latticed plate with respect to the rib's angle are presented using a general-purpose computation package.