Budownictwo i Inżynieria Środowiska
2018.027, DOI: 10.7862/rb.2018.27
CRITICAL TEMPERATURE EVALUATION FOR A STEEL FRAME WITH JOINT STIFFNESS DECREASING IN FIRE
Mariusz MAŚLAK, Michał PAZDANOWSKI, Małgorzata SNELA
Submitted by: Artur Szalacha
DOI: 10.7862/rb.2018.27
Abstract
A procedure to determine the critical temperature of a selected steel frame bearing structure is presented and discussed. This temperature, in case of fully developed fire, when the temperature of the exhaust gasses enveloping the structural members is equalized within the whole fire zone, may be considered as an impartial measure of safety. The obtained result does not depend on the heating progress but only on the static scheme and the load level in the considered structure. The quantitative and qualitative evaluation of the influence the joint stiffness decreasing in fire exerts on the resultant critical temperature constitutes the basic objective of the authors. It has been shown, that proceeding according to the recommended computational procedure does not necessarily result in an estimate fully unambiguous in interpretation. The critical temperature specified in a global mode, for the whole considered frame, is usually associated with a specific component of such frame, interpreted as the so called “weakest link”. Thus local loss of bearing capacity in such element is in this approach equivalent to the total destruction of the whole bearing structure. Indication, which of the components present in the considered frame should be treated as the critical one, because of its behaviour under fire conditions, seems to be a key to the forecast safety level warranted to the users of the structure. The authors show, that this association changes depending on the selected computational method, and this in turn substantially limits the reliability of the obtained estimate.
References
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About this Article
TITLE:
CRITICAL TEMPERATURE EVALUATION FOR A STEEL FRAME WITH JOINT STIFFNESS DECREASING IN FIRE
AUTHORS:
Mariusz MAŚLAK (1)
Michał PAZDANOWSKI (2)
Małgorzata SNELA (3)
AUTHORS AFFILIATIONS:
(1) Cracow University of Technology
(2) Cracow University of Technology
(3) Lublin University of Technology
SUBMITTED BY:
Artur Szalacha
JOURNAL:
Budownictwo i Inżynieria Środowiska
2018.027
KEY WORDS AND PHRASES:
steel bearing frame, fire, critical temperature, joint stiffness, moment – rotation relationship, weakest link
FULL TEXT:
http://doi.prz.edu.pl/pl/pdf/biis/1045
DOI:
10.7862/rb.2018.27
URL:
http://dx.doi.org/10.7862/rb.2018.27
COPYRIGHT:
Publishing House of Rzeszow University of Technology Powstańców Warszawy 12, 35-959 Rzeszow