Patent ID: 8840980

Claim:
Stiffened structure, comprising: primary stiffeners ( 14 . 1 , 14 . 2 , 14 . 3 ) located on a panel ( 24 ); nodes ( 12 ) located where three primary stiffeners ( 14 . 1 , 14 . 2 , 14 . 3 ) of different directions intersect, with surfaces of the three primary stiffeners ( 14 . 1 , 14 . 2 , 14 . 3 ) being arranged in planes that are perpendicular to a same plane of the panel ( 24 ); at least one opening ( 26 ); peripheral stiffeners ( 40 ) located on the panel ( 24 ), each of the peripheral stiffeners ( 40 ) running in a same direction as a adjacent one of the primary stiffeners ( 14 . 1 , 14 . 2 , 14 . 3 ); and a hexagonal belt formed, at least in part, by the peripheral stiffeners ( 40 ), the hexagonal belt surrounding said at least one opening ( 26 ) and having an inside surface facing the one opening ( 26 ).