ANDERSON LOCALIZATION PHENOMENON IN PERIODIC STRUCTURES

We study the occurrence in structures of a phenomenon similar to Anderson localization. This the vibration modes localization in structures composed. of several nominally identical lightly coupled modular substructures. In an ideal perfect model, the vibration modes are global in nature, spreading to the whole structure. In real structures there are no two completely identical segments. Constructive or loading imperfections generate slight variation of the dynamic characteristics of each module. As the level of disorder grows and coupling between modules becomes lighter, the resulting vibration modes change considerably. Vibration energy may become confined to a few segments. This is the Mode Localization Phenomenon. We present models of long modular planar trussed structures. Light coupling is considered between the initially identical modules. A certain degree of imperfection is introduced by adopting a slight variation in the loading of the modules. This will generate a small variation in the global stiffness of the system as the axial loads in the bars affect their Geometric Stiffness Matrices.