An integrated approach to shape and laminate stacking sequence optimization of free-form FRP shells

Efficient use of fiber-reinforced polymer (FRP) composites in civil structures will require developing new forms that are conducive to their dominant in-plane mechanical properties. For this goal, an approach for the shape and stacking sequence optimization of free-form FRP shells was developed. The process was uncoupled into continuous- and discrete-variable problems and implemented in a two-level procedure: shape and laminate-property optimization followed by laminate stacking sequence optimization. Examples show the benefits of integrated shape and laminate optimization for FRP structures, and validate the method for the mixed variable problem and for different number of plies and intervals of ply orientations.