...
Significant axial-force discrepancy between adjacent columns expected to demonstrate similar response indicates excessive c K K j damping contribution. This effect will magnify with shorter columns because their axial stiffness, and K j value, is larger. Given a dynamic loading condition, the cyclic bending of concrete sections will generate axial velocity. As cracking and the ratcheting of yielding tensile rebar increase axial extension, velocity can become significant. This will cause improper damping to further effect impact results.
Given such an instance, users should reduce stiffness-proportional damping in column elements through the following process:
...