Resistance Mechanisms in RC Building Frames Subjected to Column Failure

Abstract

There is a damage potential for the columns of building frames due to either unexpected causes such as vehicle impact, boiler explosion, or terrorist attack, or due to design or construction deficiencies aggravated by an earthquake, severe wind, or excessive foundation movement. This paper investigates the redistribution paths of released forces resulting from a column failure and identifies the basic structural defense mechanisms developed in a damaged building frame. Extensive analytical studies revealed that the effect of a column failure is localized to the beams connected to the vertical axis of the failed column and to the adjacent columns. Although the load‐carrying capacity of the connected beams is far exceeded by the redistributed forces, the presence of even light architectural infill walls reduces the beam forces remarkably. It is observed and analytically demonstrated that a partially infilled building frame may survive a base‐column failure without any damage to the other members. Further, it is shown that the redistributed internal forces can be predicted with reasonable accuracy by employing basic structural analysis.