Abstract

The assumptions of frame supports being fully rigid and distributed masses and deformations of the columns being neglected are frequently taken into consideration in dynamic analysis of plane frames. In practice, however, column bases of frames may usually rotate and translate a little due to seismic effects. In this case, support behavior can be modeled using elastic springs at the column bases of frames. Besides, columns, in fact, are not massless, and have distributed mass and stiffness. In this study, the support of the frame modeled as Timoshenko column is modeled by elastic springs against rotation and translation. The generalized equation of motion is obtained by Lagrange equation using energy relations of the system, the dynaimc response is computed for different elastic spring coefficients using incremental Newmark-β method, and response spectra are obtained using ground accelerations of 1999 Izmit earthquake.