ラティス円筒構造の座屈モードにおける局所回転の影響

抄録

Much attention is paid to lattice structures as effective structural elements for aerospace applications. Lattice structure has periodic system made of discrete beam-like ribs. Under compressive force, ribs may deform in the lattice plane as well as out of plane and cause local rotation in the unit cell. Though this local rotation can make a difference between the buckling modes of lattice and homogeneous shell structures, it has not been considered properly in the previous lattice design. This study focuses on the local rotation that is unique to lattice structures and clarifies its effects on buckling modes using finite element method (FEM). The buckling analysis of unit cell structure shows qualitative and quantitative correspondence with experimental and analytical results. This analytical model shows that the buckling load of whole structure with design values derived by the previous study which neglects local rotation is far below the target load. It clearly shows the defect of the previously proposed design procedure. Moreover, additional analyses with different design values provide unexpected buckling modes in which local rotation cannot be neglected. This suggests the importance of considering the effects of local rotation on buckling modes in the design phase.