Abstract
This paper studies the elasto-plastic dynamic behaviors of steel cantilever columns with variable cross-section subjected to horizontal earthquake ground motion An analytical procedure based on the implicit time integration technique is developed for columns with multi-degrees of freedom The numerical results aimed at the collapse patterns of columns indicate the coupled behaviors between sway and vertical vibration as well as change of collapse patterns due to Pδ effects. It is concluded from the efficiency of the absorbed strain energy corresponding to cumulative plastic strain every cross-section that the favorable collapse pattern from a point of seismic design view is to restrict the plastic deformation within the lower cross-section of columns.
