Negative stiffness elements in a lumped system allows high damping. Columns with press-fit ends provide stiffness and the capability of snap-through hysteresis. Analysis shows optimal material damping to minimize oscillation after impact. Small amplitude oscillation experiments reveal column buckling gives rise to giant damping only for the end tilt condition, not the pin end or built in conditions. Large hysteresis occurs in post-buckling provided flat end rods can tilt so contact goes from surface to edge. Negative incremental stiffness in these systems occurs in the post buckling regime. Use of columns with flat ends, free to tilt, allows high damping combined with high stiffness equal to that of parent material, shown in experiment. Stable steel modules based on this concept exhibit high stiffness and high damping as shown in experiment. Effective tan delta exceeds 1.9 in tuned systems. Effective modulus tan delta product exceeds 200 GPa in tuned systems. |