Bidirectional Seismic Energy Input to an Isotropic Nonlinear One-Mass Two-Degree-of-Freedom System

The test results obtained for reinforced concrete columns by several studies have revealed that the peak displacement and cumulative hysteresis energy are important parameters evaluating damage of under horizontal bidirectional unidirectional loading. Therefore, seismic related to nonlinear with regard input should be investigated. In this study, an isotropic one-mass two-degree-of-freedom system was evaluated. First, a dimensionless parameter ?, which controls low-cycle fatigue effect, formulated as function two (the maximum momentary total energy) (ductility normalized absorption during half cycle). Then, were evaluated according ground motion characteristics (Fourier coefficient components) properties. Finally, ? on basis energy. can properly using parameters.