ABSTRACT
A series of nonlinear time history analyses were performed to simulate the seismic behavior of MRFs with SC column bases. Instead of a member-bymember model, a fishbone model was adopted for simulation to generalize the responses. Adopting the assumption that all lateral displacements and rotations at joints lying at each floor are identical and the inflexion points of all beams are located at mid span, all columns in each story were condensed to one representative column element, and all beams and panel zones at each floor level were condensed to one rotational spring element. To consider the effect of column base, a rotational spring was added at the base of the representative column element. All elements in the fishbone model were characterized to be nonlinear to capture their post-yielding behavior. The P-Δ effect was considered in simulation.
