Secondary language: |
English |
Secondary title: |
Simplified calculation methods for the fire design of RC beams |
Secondary abstract: |
This thesis presents simplified calculation methods for evaluating the fire resistance of reinforced
concrete (RC) beams in accordance with the SIST EN 1992-1-2:2005 standard. The methods presented
are the 500°C isotherm method and the zone method. With both methods, the fire analysis is divided
into two mathematically separate steps: thermal and mechanical. Thermal analysis is used to predict
temperature development in the beam, taking into consideration the relevant heat source and
temperature-dependent thermal and mechanical properties of materials. This step of the analysis is the
same for both simplified methods. In the second part of the fire analysis, the axial and bending
resistance of the characteristic cross section of the RC beam is determined, taking account of the
reduced cross section and the strength reduction of reinforcing bars. The 500°C isotherm method
determines the reduced dimensions of cross sections, based on the 500°C isotherm. Using the zone
method, the size of the affected area is calculated by dividing the cross section into several zones, for
which the temperature conditions are evaluated. The zone method is more accurate than the 500°C
isotherm method. In the calculation example, the fire resistance of the simply supported RC beam
located over the living space in a single-family house is evaluated using the two methods. It is
established that the fire resistance results acquired by both methods differ only marginally. |
Secondary keywords: |
graduation thesis;fire resistance;simplifield calculation methods;RC beam;temperature; |
File type: |
application/pdf |
Type (COBISS): |
Bachelor thesis/paper |
Thesis comment: |
Univ. v Ljubljani, Fak. za gradbeništvo in geodezijo |
Pages: |
XV, 54 str. |
Type (ePrints): |
thesis |
Title (ePrints): |
Simplified calculation methods for the fire design of RC bears |
Keywords (ePrints): |
požarna odpornost;poenostavljene računske metode;AB nosilec;temperatura |
Keywords (ePrints, secondary language): |
fire resistance;simplified calculation methods;RC beam;temperature |
Abstract (ePrints): |
V diplomski nalogi predstavimo poenostavljeni računski metodi za oceno poţarne odpornosti
armiranobetonskih (AB) nosilcev skladno s standardom SIST EN 1992-1-2:2005. To sta metoda
izoterme 500°C in metoda območij. Pri obeh metodah je poţarna analiza razdeljena v dva
matematično nepovezana dela, na temperaturni del in mehanski del. S temperaturno analizo določimo
razvoj temperature v nosilcu glede na merodajni toplotni vpliv in ob upoštevanju temperaturno
odvisnih toplotnih in mehanskih lastnosti materialov. Ta del analize je enak pri obeh poenostavljenih
metodah. V drugem delu poţarne analize ob upoštevanju zmanjšanega prečnega prereza in reduciranih
trdnosti armaturnih palic določimo osno-upogibno odpornost karakterističnega prečnega prereza AB
nosilca. Pri metodi izoterme 500°C reducirane dimenzije prereza določimo na podlagi poteka izoterme
500°C. Pri metodi območij širino poškodovanega območja izračunamo s pomočjo razdelitve prečnega
prereza na več območij, za katere ocenimo temperaturne pogoje. Metoda območij je natančnejša od
metode izoterme 500°C. V računskem primeru s predstavljenima metodama ocenimo poţarno
odpornost prostoleţečega AB nosilca, ki se nahaja nad dnevno bivalnim prostorom v enodruţinski
stanovanjski hiši. Ugotovimo, da se poţarni odpornosti po obeh metodah minimalno razlikujeta. |
Abstract (ePrints, secondary language): |
This thesis presents simplified calculation methods for evaluating the fire resistance of reinforced
concrete (RC) beams in accordance with the SIST EN 1992-1-2:2005 standard. The methods presented
are the 500°C isotherm method and the zone method. With both methods, the fire analysis is divided
into two mathematically separate steps: thermal and mechanical. Thermal analysis is used to predict
temperature development in the beam, taking into consideration the relevant heat source and
temperature-dependent thermal and mechanical properties of materials. This step of the analysis is the
same for both simplified methods. In the second part of the fire analysis, the axial and bending
resistance of the characteristic cross section of the RC beam is determined, taking account of the
reduced cross section and the strength reduction of reinforcing bars. The 500°C isotherm method
determines the reduced dimensions of cross sections, based on the 500°C isotherm. Using the zone
method, the size of the affected area is calculated by dividing the cross section into several zones, for
which the temperature conditions are evaluated. The zone method is more accurate than the 500°C
isotherm method. In the calculation example, the fire resistance of the simply supported RC beam
located over the living space in a single-family house is evaluated using the two methods. It is
established that the fire resistance results acquired by both methods differ only marginally. |
Keywords (ePrints, secondary language): |
fire resistance;simplified calculation methods;RC beam;temperature |
ID: |
8311998 |