Eurocodes applied to fire scenarios From a fire scenario to dimensioning [email protected]

Eurocodes applied to fire scenariosFrom a fire scenario to dimensioning

[email protected]

What are the Eurocodes?

A series of textbooks

containing recommendations

for calculating

the stability

of building structures

Redaction started in 1975, the Eurocodes were written on a voluntary base (by professional associations) with the support of the C.E.C., then a mandate was given to CEN in 1989.

Eurocodes (circa 1990)

prENV

ENV (circa 1995) + National Application Documents

prEN

EN (circa 2000-2005) +National Annexes

On a voluntary baseBecause of a contract

Because of a law

Requirements


Because of a law

Utilisation of the Eurocodes

Fire resistance = ….

Which law?

Basis norms• Annex 2 (low rise buildings)• Annex 3 (middle rise buildings)• Annex 4 (high rise buildings)• Annex 6 (industrial buildings)

Regional decrees

Etc

Requirements

Because of a law


Because of a law

Requirements


Because of a law


Fire resistance = ….

Which law ?

Pour l'évaluation de la résistance au feu d'éléments de construction, on peut utiliser: soit un essai selon NBN 713-020 soit une méthode de calcul, agréée par le Ministre de l'intérieur selon la procédure et les

conditions qu'il détermine. Pour utiliser cette méthode de calcul, il peut être tenu compte de: a) l'examen de scénarios d'incendie naturels (vient ensuite la description des conditions auxquelles les calculs de ce type doivent répondre) b) l'examen de scénarios d'incendie conventionnels.

Article 2 of Annex 1 of Basis Norms.

Because of a law


The fire resistance of a building element can be demonstrated,1. either by a fire test (used to be NBN 713-020, now EN’s)2. or by a calculation method approved by the Ministry of Interior.

As of today (October 2010), there is no approved method.

The following situation might be adopted:Approved method = Eurocodes For tabulated data, calculation can be made by the person responsible of the stability under room temperature. For simple calculation models: either the designer is approved, or the calculation is checked by an approved organisation. For general calculation models (F.E.) or utilisation of any natural fire curve: Derogation Commission.

8

En cas d’exposition à la courbe température-temps (NBN EN 1363-1), les éléments structurels de type II ne peuvent pas s’affaisser pendant une durée de temps qui équivaut à la durée de temps équivalente te,d (selon EN 1991-1-2:2002) dans laquelle q1 est déterminé sur la base du risque d’échec acceptable d’effondrement égal à 10-3 par an.

De structurele elementen type II mogen bij een blootstelling aan de standaard temperatuur-tijdkromme (NBN EN 1363-1) niet bezwijken binnen een tijdspanne gelijk aan de equivalente tijdsduur te,d (bepaald op basis van de norm EN 1991-1-2:2002), waarbij q1 bepaald is op basis van een aanvaardbare faalkans van instorting gelijk aan 10-3 per jaar.

Article 3.1 of Annex 6 of Basis Norms.

Which law ?

Because of a law


Eurocode number Ambient canditions Fire conditions

Basis of design EN 1990 -

Actions EN 1991-1-1 EN 1991-1-2

Concrete structures EN 1992-1-1 EN 1992-1-2

Steel structures EN 1993-1-1 EN 1993-1-2

Composite steel-concrete structures EN 1994-1-1 EN 1994-1-2

Timber structures EN 1995-1-1 EN 1995-1-2

Masonry structures EN 1996-1-1 EN 1996-1-2

Geotechnical design EN 1997 -

Earthquake resistance EN 1998 -

Aluminium alloy structures EN 1999-1-1 EN 1999-1-2

From fire scenario to dimensioning: general layout

Fire Scenario

T = f(x,y,z,t)

Mechanical loadsin the fire situation

M, N, V

Design methodR = x minutes

Thermal calculationMechanical calculation

Eurocode number Ambient canditions Fire conditions

Basis of design EN 1990 -

Actions EN 1991-1-1 EN 1991-1-2

Concrete structures EN 1992-1-1 EN 1992-1-2

Steel structures EN 1993-1-1 EN 1993-1-2

Composite steel-concrete structures EN 1994-1-1 EN 1994-1-2

Timber structures EN 1995-1-1 EN 1995-1-2

Masonry structures EN 1996-1-1 EN 1996-1-2

Geotechnical design EN 1997 -

Earthquake resistance EN 1998 -

Aluminium alloy structures EN 1999-1-1 EN 1999-1-2

From fire scenario to dimensioning: general layout

Fire Scenario

T = f(x,y,z,t)

Mechanical loads

M, N, V

Design methodR = x minutes

F0F0

F0

F0

F0F0

F0

F0

F0F0

F0

F0F0F0

F0

F0

F0F0F0F0F0

F0F0F0F0F0

F0F0

F0

F0F0F0

F0

F0

F0F0F0

F0F0 F0F0 F0F0 F0F0 F0F0

F0F0

F0

F0


F0F0

F0

F0

F0F0 F0F0 F0F0

X Y

Z

Diamond 2009.a.5 for SAFIR

FILE: bat

NODES: 1077

BEAMS: 520

TRUSSES: 0

SHELLS: 0

SOILS: 0

BEAMS PLOT

IMPOSED DOF PLOT

Beam Elem ent

From fire scenario to dimensioningMethod 1: Tabulated data

ISO fire

T = f(x,y,z,t)

Pd,fi = Gk

+ 0.5 qk,1

Load ratio mfi = pd,fi / pd

Tabulated dataElement by element

R = x minutes

F0F0

F0

F0

F0F0

F0

F0

F0F0

F0

F0F0F0

F0

F0

F0F0F0F0F0

F0F0F0F0F0

F0F0

F0

F0F0F0

F0

F0

F0F0F0


F0F0

F0

F0


F0F0

F0

F0

F0F0 F0F0 F0F0

X Y

Z


FILE: bat

NODES: 1077

BEAMS: 520

TRUSSES: 0

SHELLS: 0

SOILS: 0

BEAMS PLOT

IMPOSED DOF PLOT

DISTRIBUTED LOADS PLOT

Beam Elem ent

T = f(t)

Pd,fi = Gk

+ 0.5 qk,1

M, N ,V at t = 0

Simple calculation modelElement by element

R = x minutes

From fire scenario to dimensioningMethod 2: Simple calculation model

ISO fire

F0F0

F0

F0

F0F0

F0

F0

F0F0

F0

F0F0F0

F0

F0

F0F0F0F0F0

F0F0F0F0F0

F0F0

F0

F0F0F0

F0

F0

F0F0F0


F0F0

F0

F0


F0F0

F0

F0

F0F0 F0F0 F0F0

X Y

Z


FILE: bat

NODES: 1077

BEAMS: 520

TRUSSES: 0

SHELLS: 0

SOILS: 0

BEAMS PLOT

IMPOSED DOF PLOT


Beam Elem ent

X Y

Z

5.0 E+04 Nm


FILE: bat

NODES: 1077

BEAMS: 520

TRUSSES: 0

SHELLS: 0

SOILS: 0

BEAMS PLOT

My BENDING MOMENT PLOT

TIME: 4 sec

T = f(x,y,t)

Pd,fi = Gk

+ 0.5 qk,1

M, N ,V at t = 0

From fire scenario to dimensioningMethod 3: Advanced calculation model

Any fire

Advanced calculation modelFor the whole structure

R = x minutes

F0F0

F0

F0

F0F0

F0

F0

F0F0

F0

F0F0F0

F0

F0

F0F0F0F0F0

F0F0F0F0F0

F0F0

F0

F0F0F0

F0

F0

F0F0F0


F0F0

F0

F0


F0F0

F0

F0

F0F0 F0F0 F0F0

X Y

Z


FILE: bat

NODES: 1077

BEAMS: 520

TRUSSES: 0

SHELLS: 0

SOILS: 0

BEAMS PLOT

IMPOSED DOF PLOT


Beam Elem ent

X

Y

Z


FILE: colunmv3

NODES: 983

ELEMENTS: 1868

CONTOUR PLOT

TEMPERATURE PLOT

TIME: 3600 sec>Tmax

1000.00

900.00

800.00

700.00

600.00

500.00

400.00

300.00

200.00

100.00

26.00

Thank you