Performance of parking steel column damaged by fire

2019 ◽  
Vol 10 (2) ◽  
pp. 138-154
Author(s):  
Farshid Masoumi ◽  
Ebrahim Farajpourbonab

Purpose The primary purpose of this research was to expand the knowledge base regarding the behavior of steel columns during exposure to fire. This paper presents the numerical study of the effect of heat on the performance of parking steel column in a seven-story steel building under cyclic loading. Design/methodology/approach In this research, the forces and deformations developed during a fire are estimated by using detailed 3D finite-element models. The analyses are in the form of a coupled thermo-mechanical analysis in two types of loading: concurrent loading (fire and cyclic loading) and non-concurrent loading (first fire and then cyclically), and the analyses have been conducted in both states of the fire loading with cooling and without cooling using the ABAQUS software. Further, it was investigated whether, during the fire loading, the specimen was protected by a 3-cm-thick concrete coating and how much it changes the seismic performance. After verification of the specimen with the experimental test results, the column model was investigated under different loading conditions. Findings The result of analyses indicates that the effect of thermal damage on the performance of steel columns, when cooling is happening late, is more than the state in which cooling occurs immediately after the fire. In this paper, thermal–seismic performance of parking steel columns has been specified and the effect of the fire damage has been investigated for the protected steel by concrete coating and to the non-protected steel, under both cooling and non-cooling states. Originality/value This study led to recommendations based on the findings and suggestions for additional work to support performance-based fire engineering. It is clear that predicting force and deformation on steel column during fire is complex and it is affected by many variables. Here in this paper, those variables are examined and proper results have been achieved.

Author(s):  
Xiangyong Ni ◽  
Shuangyin Cao ◽  
Hassan Aoude

This study examines the influence of cross-section shape on the seismic behaviour of high-strength steel reinforced concrete shear walls (HSS-RC) designed with Grade HRB 600 MPa reinforcement. As part of the study, two flexure-dominant walls with rectangular and T-shaped cross-sections, are tested under reversed cyclic loading. Seismic performance is evaluated by studying the failure characteristics, hysteretic curves, energy dissipation, ductility and reinforcing bar strains in the two walls. As part of the numerical study, two-dimensional (2D) and three-dimensional (3D) finite element modelling (FEM) are used to predict the seismic response of the rectangular and T-shaped walls, respectively. The test results show that compared to the rectangular wall, the flange in the T-shaped HSS-RC wall increased strength, energy dissipation and stiffness, but decreased ductility. The analytical hysteretic curves calculated using 2D and 3D FEM analyses show good agreement with the experimental test results.


2019 ◽  
Vol 11 (2) ◽  
pp. 167-187
Author(s):  
Andrei Kervalishvili ◽  
Ivar Talvik

Purpose This paper aims to reliability analysis of axially loaded steel columns at elevated temperatures considering the probabilistic features of fire. Design/methodology/approach The response function used in the reliability analysis is based on the non-linear FEM calculations. The stochastic variability of temperature is integrated with the procedure similar to the parameters of loading and material properties. Direct Monte Carlo simulations (MCSs) are implemented for probabilistic analysis. Computational costs are reduced by polynomial approximation of the response function of the column. Findings A design method for practical applications in the common Eurocode format is proposed. The proposed method can be used to estimate the failure probability of a steel column in fire conditions. If standard reliability criteria are applied, the results of the steel column buckling capacity in the fire according to the proposed procedure deviate from the Eurocode results in certain parameter ranges. Originality/value The proposed method for design calculations makes use of the advantages of MCS results, while the need for the tedious amount of calculations for the end user are avoided as the predefined factors are implemented in the procedure of Eurocode format. The proposed method allows better differentiation of the fire probability in the capacity assessment compared to the existing design methods.


2013 ◽  
Vol 302 ◽  
pp. 347-354
Author(s):  
Ze Feng Ma ◽  
Zhou Dao Lu ◽  
Jiang Tao Yu ◽  
Zi Hong Cai

In order to research seismic behavior of flat columns under bilateral cyclic loading with different angles, pseudo-static tests are conducted, which includes three 1:2 scaled flat columns. The height-width ratio of the column section is 5. And the loading directions are 00, 250 and 450 respectively. By observation of the test phenomenon and analysis of the data, the seismic performance of the columns including stiffness, skeleton curves, hysteresis curves, ductility and energy dissipation are obtained. Moreover, finite element program ANSYS is employed to simulate the bearing capacity of specimens. The research shows that with the loading angles increasing from 0 to 45, the strength of the flat column decreased gradually, while the ductility and energy dissipation capacity increase, and the failure mode changed from compression-shear to compression-bending. P-Δ effect becomes evident at lager values of loading angle. The compression-shearing curve of flat column complies with a heart-shape curve.


2017 ◽  
Vol 8 (3) ◽  
pp. 300-323 ◽  
Author(s):  
Jean-Marc Franssen ◽  
Thomas Gernay

Purpose This paper aims to describe the theoretical background and main hypotheses at the basis of SAFIR®, a nonlinear finite element software for modeling structures in fire. The paper also explains how to use the software at its full extent. The discussed numerical modeling principles can be applied with other similar software. Design/methodology/approach Following a general overview of the organization of the software, the thermal analysis part is explained, with the basic equations and the different possibilities to apply thermal boundary conditions (compartment fire, localized fire, etc.). Next, the mechanical analysis part is detailed, including the time integration procedures and the different types of finite elements: beam, truss, shell, spring and solid. Finally, the material laws are described. The software capabilities and limitations are discussed throughout the paper. Findings By accommodating multiple types of finite elements and materials, by allowing the user to consider virtually any section type and to input the fire attack in multiple forms, the software SAFIR® is a comprehensive tool for investigating the behavior of structures in the fire situation. Meanwhile, being developed exclusively for its well-defined field of application, it remains relatively easy to use. Originality value The paper will improve the knowledge of readers (researchers, designers and authorities) about numerical modeling used in structural fire engineering in general and the capabilities of a particular software largely used in the fire engineering community.


2012 ◽  
Vol 193-194 ◽  
pp. 1405-1413 ◽  
Author(s):  
Zhu Ling Yan ◽  
Bao Long Cui ◽  
Ke Zhang

This paper conducts analysis on beam-column extended end-plate semi-rigid connection joint concerning monotonic loading and cyclic loading of finite element through ANSYS program, mainly discussed the influence of parameters such as the form of end plate stiffening rib on anti-seismic performance of joint.


2020 ◽  
Vol 36 (2_suppl) ◽  
pp. 288-313
Author(s):  
Juan M Mayoral ◽  
Gilberto Mosqueda ◽  
Daniel De La Rosa ◽  
Mauricio Alcaraz

Seismic performance of tunnels during earthquakes in densely populated areas requires assessing complex interactions with existing infrastructure such as bridges, urban overpasses, and metro stations, including low- to medium-rise buildings. This article presents the numerical study of an instrumented tunnel, currently under construction on stiff soils, located in the western part of Mexico City, during the Puebla-Mexico 19 September 2017 earthquake. Three-dimensional finite difference models were developed using the software FLAC3D. Initially, the static response of the tunnel was evaluated accounting for the excavation technique. Then, the seismic performance evaluation of the tunnel was carried out, computing ground deformations and factors of safety, considering soil nonlinearities. Good agreement was observed between predicted and observed damage during post-event site observations. Once the soundness of the numerical model was established, a numerical study was undertaken to investigate the effect of frequency content in tunnel-induced ground motion incoherence for tunnels built in cemented stiff soils. A series of strong ground motions recorded during normal and subduction events were used in the simulations, considering a return period of 250 years, as recommended in the Mexico City building code. From the results, it was concluded that the tunnel presence leads to important frequency content modification in the tunnel surroundings which can affect low- to mid-rise stiff structures located nearby. This important finding must be taken into account when assessing the seismic risk in highly populated urban areas, such as Mexico City.


Author(s):  
Joon Young Yoon ◽  
Seong Hwan Kim ◽  
Gwon Cheol Yu ◽  
Jung Kwan Seo ◽  
Bong Ju Kim ◽  
...  

The aim of this paper is to examine the effect of wind on the thermal diffusion characteristics of floating production storage and offloading (FSPO) topside models subject to fire. It is motivated by the need to identify the fire loads on FPSO topsides, taking into account the effects of wind speed and direction. The results of an experimental and numerical study undertaken for these purposes are reported here. This paper is part of Phase II of the joint industry project on explosion and fire engineering of FPSOs (EFEF JIP) [1]. An experiment was performed on a 1/14-scale FPSO topside model using a wind tunnel test facility. The locations of the heat source of the fire were varied, as were the speed and direction of the wind, and the temperature distribution was measured. Computational fluid dynamics (CFD) simulations using the ANSYS CFX program were performed on the test model, with the results obtained compared with the experimental results. It is concluded that wind has a significant effect on the thermal diffusion characteristics of the test model and that the CFD simulations are in good agreement with the experimental results. The insights developed in this study will be very useful for the fire engineering of FPSO topsides.


Author(s):  
Jeong Hyo Park ◽  
Bong Ju Kim ◽  
Jung Kwan Seo ◽  
Jae Sung Jeong ◽  
Byung Keun Oh ◽  
...  

The aim of this study was to evaluate the load characteristics of steel and concrete tubular members under jet fire, with the motivation to investigate the jet fire load characteristics in FPSO topsides. This paper is part of Phase II of the joint industry project on explosion and fire engineering of FPSOs (EFEF JIP) [1]. To obtain reliable load values, jet fire tests were carried out in parallel with a numerical study. Computational fluid dynamics (CFD) simulation was used to set up an adiabatic wall boundary condition for the jet fire to model the heat transfer mechanism. A concrete tubular member was tested under the assumption that there is no conduction effect from jet fire. A steel tubular member was tested and considered to transfer heat through conduction, convection, and radiation. The temperature distribution, or heat load, was analyzed at specific locations on each type of member. ANSYS CFX [2] and Kameleon FireEx [3] codes were used to obtain similar fire action in the numerical and experimental methods. The results of this study will provide a useful database to determine design values related to jet fire.


2011 ◽  
Vol 243-249 ◽  
pp. 1435-1438 ◽  
Author(s):  
Ming Chen ◽  
Yang Sun ◽  
Bing Qian Pi

The double C steel section is made of two C steels with gusset plate through bolts. A ridge joint of double C steel is studied through experiment under cyclic loading in this paper. Through the four specimens with different gusset-plate’s thickness and bolt spacing, we analyze the effect of the gusset-plate’s thickness and bolt spacing on stiffness, ductility and energy performance. At last we recommend the suitable gusset-plate’s thickness. The results can give a reference to the engineering application of cold-formed steel structure.


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