Critical Temperature Evaluation for a Steel Frame with Joint Stiffness Decreasing in Fire

• Autorzy: Maślak M. , Pazdanowski M. , Snela M.

Identyfikatory

DOI

10.7862/rb.2018.27

• Języki publikacji: EN

Abstrakty

EN

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.

Słowa kluczowe

EN

steel bearing frame; fire; critical temperature; joint stiffness; moment-rotation relationship; weakest link

• Wydawca: Oficyna Wydawnicza Politechniki Rzeszowskiej
• Czasopismo: Czasopismo Inżynierii Lądowej, Środowiska i Architektury / Journal of Civil Engineering, Environment and Architecture
• Rocznik: 2018
• Tom: z. 65, nr 2
• Strony: 91--101
• Opis fizyczny: Bibliogr. 8 poz., rys., tab.

Twórcy

autor

Maślak M.

• Cracow University of Technology, Faculty of Civil Engineering, Chair on Metal Structures, Warszawska 24, 31-155 Cracow, phone: [phone]

autor

Pazdanowski M.

• Cracow University of Technology, Faculty of Civil Engineering, Institute for Computational Civil Engineering, Warszawska 24, 31-155 Cracow, phone: [phone]

autor

Snela M.

• Lublin University of Technology, Faculty of Civil Engineering and Architecture, Department of Structural Engineering, Nadbystrzycka 40, 20-618 Lublin, phone: [phone]

Bibliografia

• [1] EN 1993-1-1, Eurocode 3: Design of steel structures, Part 1-1: General rules and rules for buildings.
• [2] Autodesk, Robot Structural Analysis 2010. User manual.
• [3] EN 1993-1-2, Eurocode 3: Design of steel structures, Part 1-2: General rules - Structural fire design.
• [4] EN 1990, Eurocode: Basis of structural design.
• [5] Maślak M., Snela M.: Critical temperature of steel frame with joint stiffness decreasing in fire, Scientific Papers of Rzeszów University of Technology, No 283, 2012, Series „Civil and Environmental Engineering”, Vol. 59 (3/12/II), pp. 241-248 (in Polish).
• [6] Maślak M., Snela M.: Moment - rotation relationship in fire conditions for a steel beam-to-column joint of known pliability, Building and Architecture, 12 (2), 2013, pp. 237-244 (in Polish).
• [7] Maślak M., Snela M.: Flexibility of a steel end-plate beam-to-column joint when exposed to a fire - two different, nonequivalent approaches to evaluate, Proceedings of the Eighth International Conference on Advances in Steel Structures (ICASS 2015), Lisbon, Portugal, July 21-24, 2015, paper 131, CD + pen-drive, 9 p.
• [8] Maślak M., Snela M.: Influence of increasing joint flexibility on critical temperature of steel frame in fire, Zbirnik Naukowych Prac Ukrainskogo Institutu Staliewych Konstrukcij imieni W. M. Szimanowskogo, Wipusk 9/2012, Wydawnictwo “Stal”, Kiev, Ukraine, pp. 204-217.

Uwagi

Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2019).