2-D Analysis of a Building Frame under Gravity Load and Fire

摘要

A two-dimensional finite-element model is developed that provides some insight into the behavior and collapse of high-rise steel buildings with open web floor systems. For one prescribed temperature distribution that corresponds to a two-story, quarter-span fire, the diagonals of the heated trusses buckle inelastically, causing considerable sag in the fire floors. This behavior puts a high tension demand on the truss connections to the perimeter column, which remains at moderate temperatures in this model and does not experience buckling. Our analysis is based on temperatures and material properties that were selected for illustrative purposes. Therefore no claim is made as to its applicability to any specific structure.