Virtual Tests on Axially and Rotationally Restrained Steel Column Under Fire

Abstract

During a fire, some additional forces are imposed on columns due to varied thermal deformations in the neighboring structural components. Axial and rotational restraints can produce substantial loadings, which together with thermally reduced stiffness, can lead to its premature buckling and reduction of the column fire resistance. The paper presents a study on numerical modeling of steel columns subjected to prescribed axial and rotational restraints and time dependent temperatures. The problem is investigated using nonlinear finite element simulations carried out using the general purpose program LS-DYNA®. The paper focuses on model development and its verification and validation. Several modeling options and strategies for modeling thermal and mechanical boundary conditions have been considered. A numerical prediction of structural response during heating is compared with published experimental data.

Comparative Study of Calculation Models for the Fire Resistance of Hollow Steel Columns Filled with Concrete

“…Also, according to Kwasniewski et al [24], the main difference's sources between numerical and experimental results, particularly in the post-buckling phase, are due to simplified numerical material model and complexity of actual mechanical support conditions. Kwasniewski et al [21] also found that the postponed buckling observed during tests is due to non-uniform temperature distribution along the columns tested. Their study [21][22][23][24] shows *: % reinforcement < 1.5 % according to the Canadian standards 1.5 % ≤ ρ ≤ 5 %; +values obtained by linear interpolation;…”

“…Kwasniewski et al [21] also found that the postponed buckling observed during tests is due to non-uniform temperature distribution along the columns tested. Their study [21][22][23][24] shows *: % reinforcement < 1.5 % according to the Canadian standards 1.5 % ≤ ρ ≤ 5 %; +values obtained by linear interpolation;…”

“…This hypothesis is not consistent with the real conditions observed during laboratory tests. According to Kwasniewski et al [21], the temperature distribution along the columns tested is not uniform due to the heat transfer at the partially insulated furnace openings.…”

Random Parameters and Sources of Uncertainty in Practical Fire Safety Assessment of Steel Building Structures

“…Presentation and summary of results of numerical investigation of an axially loaded steel column, subjected to axial and rotational restraints of supports and elevated temperature, simulating fire actions, was included by Kwaśniewski, Król and Łącki in [30]. The paper discusses the outcomes of the parametric study, taking into account uncertainties arising from variability of the steel material model, the size of geometric imperfections and the variation of temperature field along the length of the column.…”

Effect of thermal expansion on three-dimensional reinforced concrete frames under high temperature

“…9 Kwasniewski investigated the entire response of structures in the event of a fire from all angles. 10 Few studies have been done on load distribution in structures after a fire. 11 The influence of masonry infill walls in reinforced concrete structures to prevent progressive collapse was demonstrated by Eren et al 12 It was also observed that the masonry infill walls present in the structures will help in energy dissipation and prevent the structures from deficient damages.…”