Nonlinear Modeling of Flat-Plate Systems

Analytical and experimental studies were undertaken to assess and improve modeling techniques for capturing the nonlinear behavior of flat-plate systems using results from shake table tests of two, approximately one-third scale, two-story reinforced concrete and posttensioned concrete slab–column frames. The modeling approach selected accounts for slab flexural yielding, slab flexural yielding due to unbalanced moment transfer, and loss of slab-to-column moment transfer capacity due to punching shear failure. For punching shear failure, a limit state model based on gravity shear ratio and lateral interstory drift was implemented into a computational platform (OpenSees). Comparisons of measured and predicted responses indicate that the proposed model was capable of reproducing the experimental results well for an isolated connection test, as well as the two shake table test specimens.