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CSI Software applies an elastic-perfectly-plastic force-deformation relationship throughout during analysis procedures. During time-history analysis, when stiff elements undergo inelastic behavior, additional measures . Users may need to be taken implement additional measures to capture the nonlinear response . This condition may be realizedof stiff elements which experience inelastic behavior during time-history analysis. Such a condition may occur, for example, when adjacent columns are expected to demonstrate comparable performance, but experience axial-force discrepancy. When initially-stiff columns are subjected to dynamic loading, inelastic cyclic bending will soften the elements through cracking and the ratcheting of yielding tensile rebar. Axial velocity and excessive c K K j damping contribution may then skew the results when generated through default settings.
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