Load transfer ustar (U*) calculation in structures under dynamic loading

To satisfy the requirements of high stiffness and lightweight structures, it is necessary to imagine the figure of an entire structure from the viewpoint of load transfer. A parameter Ustar (U*), which is independent of stress and strain, has been introduced by the authors for expressing load transfer under static loading. In the present study, we extend the definition of U* to dynamic loading. Three points: a loading point A, a support point B, and an arbitrary point C are the representative points in a structure for the conventional definition of U*. We introduced additional points D ₁, D₂, D₃,... for the expression of inertial forces under dynamic loading. New internal stiffness tensors are introduced to account for the effect of inertial forces. We find that a new internal stiffness can be expressed by the conventional internal stiffness, which implies that the high-speed computational algorism of the conventional U* is still applicable. Although the present method is intended to be applied to vehicle bodies under collision, the simple case for the plate is calculated here to verify the effectiveness of the method.