scholarly journals PERFORMANCE BASED COUPLED CFD-FEM ANALYSIS OF 3-BAY HIGH INDUSTRIAL HALL UNDER NATURAL FIRE

2016 ◽  
Author(s):  
Michal Malendowski ◽  
Adam Glema ◽  
Wojciech Szymkuc
Keyword(s):  
Heat Exposure ◽  
Fem Analysis ◽  
Structural Elements ◽  
Fire Load ◽  
Natural Fire ◽  
Standard Fire ◽  
Complex Approach ◽  
Main Emphasis ◽  
Low Probability ◽  
And Performance

In this paper, the main emphasis is put into showing differences between standard fire design of structural elements and performance based approach, that takes into account analysis of structure under natural fire. The exemplary structure is a 3-bay 65,0x110,0 m in plane and 22,0 m high industrial hall with heavy cranes. Because of the significant volume with respect to fire load, there is a low probability that the fully developed fire can occur, nonetheless regarding technological process, a significant local fire could take place and affect the neighbour structure. The most complex approach used in this work is based on coupled CFD-FEM analysis of influence of local fire onto structure.Fire exposure of structural elements is calculated by the coupling scripts, taking into account real heat exposure of section by using adiabatic surface temperature approach.

scholarly journals Temperature of Steel Columns under Natural Fire

10.14311/642 ◽  
2004 ◽  
Vol 44 (5-6) ◽  
Author(s):  
F. Wald ◽  
P. Studecká ◽  
L. Kroupa
Keyword(s):  
Mechanical Load ◽  
Fire Regimes ◽  
Structural Elements ◽  
Structural Behaviour ◽  
Fire Load ◽  
Natural Fire ◽  
Steel Columns ◽  
Standard Fire ◽  
Frame Building ◽  
Temperature Development

Current fire design models for time-temperature development within structural elements as well as for structural behaviour are based on isolated member tests subjected to standard fire regimes, which serve as a reference heating, but do not model natural fire. Only tests on a real structure under a natural fire can evaluate future models of the temperature developments in a fire compartment, of the transfer of heat into the structure and of the overall structural behaviour under fire.To study overall structural behaviour, a research project was conducted on an eight storey steel frame building at the  Cardington Building Research Establishment laboratory on January 16, 2003. A fire compartment 11×7 m was prepared on the fourth floor. A fire load of 40 kg/m2 was applied with 100 % permanent mechanical load and 65 % of imposed load. The paper summarises the experimental programme and shows the temperature development of the gas in the fire compartment and of the fire protected columns bearing the unprotected floors.

Vulnerability of Drop Ceilings in Roadway Tunnels to Fire-Induced Damage

2021 ◽  
pp. 036119812110266
Author(s):  
Ziyan Ouyang ◽  
Qi Guo ◽  
Spencer E. Quiel ◽  
Clay J. Naito
Keyword(s):  
Fire Hazard ◽  
Heat Exposure ◽  
Element Analysis ◽  
Passive Protection ◽  
Cooling Period ◽  
Flexural Response ◽  
Standard Fire ◽  
Significant Damage ◽  
The Finite Element Analysis ◽  
Simultaneous Loss

Roadway tunnels often include a reinforced concrete drop ceiling that is hung from the liner to create a plenum that facilitates ventilation and houses utilities. Drop ceiling panels are lightweight compared with the much thicker tunnel liner and can experience significant damage from a fire on the roadway below. This paper examines the flexural response of drop ceiling panels in two representative tunnels to standard fire curves as well as several realistic fires due to vehicular accidents. Standard fire demands as per the Rijkswaterstaat and ASTM E1529 fire curves are uniformly applied to the ceiling panels, and heat exposure contours for typical vehicle fires with heat release rates of 30, 100, and 200 MW are generated from the software CFAST. The finite element analysis software SAFIR is used to evaluate the thermo-mechanical behavior of the ceiling panels when subjected to various thermal demands from the fire below. The analysis results indicate that drop ceiling panels are highly vulnerable to fire-induced damage and potential collapse both during a fire’s active heating phase (from simultaneous loss of capacity and restraint of thermal expansion) and during the subsequent cooling period (from tension that develops when the permanently deformed panel thermally retracts). The potential for fire-induced damage or collapse of the drop ceiling panels can be mitigated by reducing the fire hazard, removing the drop ceiling, or enhancing the fire resistance of the panels via the application of passive protection or structural hardening.

About quality of dissertations, or this strange GOST

2021 ◽  
pp. 65-75
Author(s):  
Yu.V. Kazakov ◽  
Keyword(s):  
Graduate Students ◽  
System Approach ◽  
Scientific Methodology ◽  
Structural Elements ◽  
Academic Degree ◽  
Practical Guide ◽  
Classical Methodology ◽  
And Performance

Examined is relevance of a subject of work is caused by the continuing deterioration of dissertation works. Therefore, article purpose is to define the system reason of deterioration of training of the top skills by the analysis of contents and structure of theses. The main shortcomings of dissertations, and understanding of their structural elements by applicants of an academic degree by communication with them in the course of preparation and carrying out preliminary protection of these were analyzed. Results of the analysis were compared to requirements of classical methodology and to interpretation of these requirements in the methodical managements and in publications. The essential system reason of decline in quality of dissertation works is in their traditional unsystematic structure, whith investigation withdrawal from scientific methodology and particular leveling of motivation to the analysis of a condition of a question and the received results of researches and also to system approach to the thesis, need of strengthening of methodological training of graduate students according to the uniform nation-wide program providing system approach to the organization of researches for all scientific specialties, and processing’s of the “Thesis and Abstract of the Thesis” standard according to classical requirements of scientific methodology and the system approach to dissertation work Is shown. The system scheme of the thesis, which can make a manual basis is the practical guide to organization and performance of dissertation work for training of graduate students and applicants is offered.

scholarly journals Some Techniques for Translator’s Text Processing Skills Development

2020 ◽  
Vol 7 (3) ◽  
pp. 51-63
Author(s):  
L.V. Enbaeva
Keyword(s):  
Foreign Language ◽  
Text Analysis ◽  
Text Comprehension ◽  
Reading Skills ◽  
Text Processing ◽  
Human Perception ◽  
Skills Development ◽  
Structural Elements ◽  
Foreign Language Reading ◽  
And Performance

Translator’s professional skills development occurs in many respects due to cognitive processes development. The study of their formation within professional tasks performance caters to the needs of its effectiveness enhancement. The existing research of human perception and text processing skills can provide a framework for translation guidelines and translation-oriented text analysis guidelines, but is rarely employed for the sake of text analysis techniques development. The aim of this study is to work out a set of techniques which simultaneously addresses text processing skills and development of translator’s competencies, connected with source text comprehension. The resulting set of techniques was motivated by postmodernist approach to translation and its idea of text semantics instability. A few techniques employed the design of Münsterberg experiment on attention and Schulte tables which are used to identify the attention selectiveness, concentration and performance capacity. The succession of techniques in a set is built according to the three-step strategy of foreign language reading skills development that comprises before-reading, while-reading and after-reading phases. The paper presents an example set of tasks for one text; they include author’s communicative aims identification, anticipation, predicative structures and multilevel semantic links eliciting, textual semantic field identifying, analysis of alternative and invariant structural elements as imposed by the conventions of the genre.

scholarly journals Practical method to predict the axial capacity of RC columns exposed to standard fire

2018 ◽  
Vol 9 (4) ◽  
pp. 266-286 ◽  
Author(s):  
Salah F. El-Fitiany ◽  
Maged A. Youssef
Keyword(s):  
Concrete Strength ◽  
Practical Method ◽  
Simple Method ◽  
Rc Columns ◽  
Content Type ◽  
Natural Fire ◽  
Rc Structures ◽  
Axial Capacity ◽  
Standard Fire ◽  
Structural Engineers

Purpose Existing analytical methods for the evaluation of fire safety of reinforced concrete (RC) structures require extensive knowledge of heat transfer calculations and the finite element method. This paper aims to propose a rational method to predict the axial capacity of RC columns exposed to standard fire. Design/methodology/approach The average temperature distribution along the section height is first predicted for a specific fire scenario. The corresponding distribution of the reduced concrete strength is then integrated to develop expressions to calculate the axial capacity of RC columns exposed to fire from four faces. Findings These expressions provide structural engineers with a rational tool to satisfy the objective-based design clauses specified in the National Code of Canada in lieu of the traditional prescriptive methods. Research limitations/implications The research is limited to standard fire curves and needs to be extended to cover natural fire curves. Originality/value This paper is the first to propose an accurate yet simple method to calculate the axial capacity of columns exposed to standard fire curves. The method can be applied using a simple Excel sheet. It can be further developed to apply to natural fire curves.

FEM Analysis of Cylindrical Structural Elements under Local Shock Loading

2014 ◽  
Vol 566 ◽  
pp. 499-504 ◽  
Author(s):  
Leopold Kruszka ◽  
Yu.S. Vorobiov ◽  
N.Yu. Ovcharova
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Strain State ◽  
Shock Loading ◽  
Dynamic Properties ◽  
Fem Analysis ◽  
Finite Deformations ◽  
High Rate ◽  
Structural Elements ◽  
Stress Strain

High rate deformations of structures cylindrical elements are considered 3D formulation. Elastic-plastic finite deformations and dynamic properties of material take into account. The problem become geometrically and physically nonlinear and finite element method is used. The numerical analyses of dynamics stress-strain state of real structures elements is executed.

scholarly journals Pipe-concrete columns of buildings and their fire-resistance determination

2018 ◽  
Vol 196 ◽  
pp. 02011
Author(s):  
Nikolay Ilyin ◽  
Nadezhda Kondratyeva ◽  
Vasily Zaiko
Keyword(s):  
Fire Resistance ◽  
Field Tests ◽  
Concrete Columns ◽  
New Method ◽  
Statistical Quality Control ◽  
Resistance Level ◽  
Natural Fire ◽  
Method Of Calculation ◽  
Standard Fire ◽  
Metal Pipes

The research recognizes the necessity of developing a new method of calculation of pipe-concrete columns fire-resistance. It is important for expending the area of their application in construction of buildings and structures; in unique structures as well. The authors apply a simplified mathematical description of the process of pipe-concrete columns resistance to the standard fire effect. This method helps to increase the accuracy of fire resistance level determination to expand these constructions use. If buildings materials are rationally combined, it is possible to produce reliable and sufficiently fireproof structures. Pipe-concrete columns which are, in fact, metal pipes filled with concrete can serve as an example of such structures. Nowadays, field tests are used to determine pipe-concrete constructions fire resistance. The authors introduce a methodology of theoretical determination of pipe-concrete columns fire resistance limit. The use of the proposed methodology makes it possible to reduce labor and economic costs while determining buildings resistance with the use of the pipe-concrete. It opens a possibility of pipe-concrete structures reasonable application in construction practice. The use of this new method allows us to determine pipe-concrete columns fire resistance without resorting to natural fire. It also increases the accuracy of statistical quality control and non-destructive tests. The calculations made in this study as well as previous tests conducted by other researches prove that there is no need for additional fire protection of pipe-concrete columns.

scholarly journals Pediatric Thermoregulation: Considerations in the Face of Global Climate Change

Nutrients ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 2010 ◽  
Author(s):  
Caroline J. Smith
Keyword(s):  
Climate Change ◽  
Ultraviolet Radiation ◽  
Global Climate Change ◽  
Global Climate ◽  
Heat Exposure ◽  
Environmental Stressors ◽  
Physiological Strain ◽  
Increased Risk ◽  
The Face ◽  
And Performance

Predicted global climate change, including rising average temperatures, increasing airborne pollution, and ultraviolet radiation exposure, presents multiple environmental stressors contributing to increased morbidity and mortality. Extreme temperatures and more frequent and severe heat events will increase the risk of heat-related illness and associated complications in vulnerable populations, including infants and children. Historically, children have been viewed to possess inferior thermoregulatory capabilities, owing to lower sweat rates and higher core temperature responses compared to adults. Accumulating evidence counters this notion, with limited child–adult differences in thermoregulation evident during mild and moderate heat exposure, with increased risk of heat illness only at environmental extremes. In the context of predicted global climate change, extreme environmental temperatures will be encountered more frequently, placing children at increased risk. Thermoregulatory and overall physiological strain in high temperatures may be further exacerbated by exposure to/presence of physiological and environmental stressors including pollution, ultraviolet radiation, obesity, diabetes, associated comorbidities, and polypharmacy that are more commonly occurring at younger ages. The aim of this review is to revisit fundamental differences in child–adult thermoregulation in the face of these multifaceted climate challenges, address emerging concerns, and emphasize risk reduction strategies for the health and performance of children in the heat.

EXPERIMENTAL STUDY ON STRUCTURAL BEHAVIOR OF FIRE PROTECTED DOUBLE CFT COLUMN SUBJECTED TO FIRE LOAD

2017 ◽  
Vol 4 (1) ◽  
Author(s):  
Kyung Soo Chung ◽  
Jae Sung Lee ◽  
Jong Eun Song ◽  
Woo Chul Kim ◽  
Heung Youl Kim ◽  
...  
Keyword(s):  
Fire Resistance ◽  
Fire Test ◽  
Failure Modes ◽  
Temperature Deformation ◽  
Fire Tests ◽  
Fire Performance ◽  
Fire Load ◽  
Standard Fire ◽  
Fire Endurance ◽  
Cft Column

New concrete filled double-tube (CFDT) sections consist of an inner and outer tube with fire protection mortar (FPM) filling the cavity between them and the inner tube also filled with concrete or not. An investigation into the fire performance of CFDT during the standard fire test is reported. Six full size FPM filled CFDT columns were designed for the fire tests. Detail failure modes of overall specimens and each component in the columns as well as temperature, deformation and fire endurance were presented. It showed that the fire resistance in the CFDT columns is significantly higher than that in concrete filled steel tubular (CFT) columns. Investigation into the fire performance of the columns reveals possible solutions to improve the fire resistance of CFT members.

Calculating Temperature Distribution in Concrete Encased H-Section Steel Column in Fires Using TFIELD

2012 ◽  
Vol 204-208 ◽  
pp. 3445-3449
Author(s):  
Yong Jun Liu ◽  
Ran Bi ◽  
Yan Wang
Keyword(s):  
Temperature Distribution ◽  
Construction Materials ◽  
Local Buckling ◽  
Steel Structure ◽  
Structural Members ◽  
Additional Advantage ◽  
Natural Fire ◽  
Standard Fire ◽  
Steel Members ◽  
Steel Column

Steel–concrete composite columns are used extensively in modern buildings in recent decades due to the benefits of combining two construction materials: reinforced concrete is inexpensive, massive, and stiff, while steel members are strong, lightweight, and easy to assemble. For concrete-encased composite structural members, an additional advantage is that the concrete used for encasing a structural steel not only increases its stiffness, but also protects it from fire damage and local buckling failure. Traditionally, the fire resistance of composite structural members has been determined in standard fire tests, with the temperature-time curves representing more severe heating conditions compared to that which occurs in many typical natural fire compartments. To design a concrete encased H-section steel structure safely and economically, it is necessary to calculate temperature distribution in composite steel-concrete columns under natural fire. In this paper, the program TFIELD written by first author is used to calculate the temperature distribution in a concrete encased H-section steel column under natural fire and ISO 834 fire. The calculating results under the standard ISO 834 fire and a natural fire have been compared which exhibit obvious differences.

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