Nonlinear seismic response calculation model of multi -ribbed composite slab structures

The multi-ribbed composite slab structure is constructed with multi-ribbed composite wall and latent frames. The ribbed-beam and ribbed-column of multi-ribbed composite wall is made of two different concrete materials. In this paper, a nonlinear macro-model is proposed to simulate the behavior of the multi-ribbed composite slab structure. The structural model is achieved using a combination of concentrated plasticity at member ends and a distributed flexibility rule that accounts for the spread of plasticity based on the variation of the contraflexure point during dynamic response. The inelastic behavior of components is monitored using a new hysteretic model that utilizes a nonsymmetric four-linear envelope and permits the modeling of stiffness degradation strength deterioration, and pinching, respectively. The structural parameters, such as moment-curvature envelopes, etc., required for the inelastic seismic response analysis are computed, using mechanical models and empirical equations that emerge from identification studies. Calculations are carried out by the IDARC nonlinear program. The calculated curves agree well with the experimental ones. The analysis shows that the macro-model is practicable.