Thermal numerical analysis of steel and steel and concrete composite columns in a fire situation aimed at the evaluation of the simplified method of ABNT NBR 14323:2013

ABSTRACT: The design of steel and concrete composite columns in a fire situation is directly linked to the reduction strength stiffness, among other properties, which are manifested response rising temperatures. normative codes that deal with these elements under action consider thermal based on heating four faces column, an aspect does not cover most cases buildings due presence walls. In this context, given importance correct determination field for purposes, as well simplification adopted by codes, present work deals exclusively study basically aimed at obtaining representative purposes thermo-structural verification columns. With focus analysis differ from prescribed configurations standards, purely numerical models proposed, validated through experimental results, whose analyses show evident temperature column when encased concrete, even greater evidence additionally inserted into walls compartmentalizing element. To verify simplified method proposed ABNT NBR 14323: 2013, comparative between fields obtained standardized model were carried out cross sections. For isolated columns, expected, proved be consistent, but conservative it came relation results indicate need adjustment standards determining and, consequently, elements.