Cardington Fire Test January 16. 2003

David Moore, František Wald, Aldina SantiagoBRE Watford, CTU in Prague, Coimbra University

TENSILE MEMBRANE ACTION AND ROBUSTNESS OF STRUCTURAL STEEL JOINTS UNDER NATURAL FIRE

EC FP5 HPRI – CV 5535

ECCS TC 10, Prague March 13-16, 2003

Cardington Laboratory

Structural Integrity Test

Preparation

Temperatures

Connections

Composite slab

Conclusion

Contents

Cardington, Hangar

Experimental area 48m x 65m x 250m

Timber structure - 5 floor

Concrete structure - 7 floor

Erected 1993

Eight floors

Plan area - 945 m2

Steel braced frame

Connections:

beam-column connections:

flexible end plates

beam-beam connections:

fin plates

Steel composite structure

Typical composite structure

Cardington Laboratory

Structural Integrity Test

Preparation

Temperatures

Connections

Composite slab

Conclusion

Contenta

Fire experiments

24 m2 ECSC

324 m2 BS

area 52,5 m2 ECSC

77 m2 ČVUT

70 m2 SCI

54 m2 SCI

136 m2 BS

- 3

- level 7

- level 4

- level 3

- level 2

++22222

- level 2 - level 4

4

3

2

1

9000

60

00

6000

A B C D E F 9000 9000 9000 9000 9000

Test Description Fire compartment Loading size, m area, m2 Fire Mech. G + % Q

1 One beam 8 x 3 24 Gas 30%2 One frame 21 x 2,5 53 Gas 30%3 Corner comp. 10 x 7 70 45 kgm-2 30%4 Corner comp. 9 x 6 54 45 kgm-2 30%5 Large comp. 21 x 18 342 40 kgm-2 30%6 Office 18 x 9 136 46 kgm-2 30%7 Integrity 11 x 7 77 40 kgm-2 56%

Summary of fire tests

Summary of duration, temp and deformations

Test Org. Level Duration Temperatures, °C Deformation, mm (mins). Atmos steel maximal residual

1 BS 7 170 913 875 232 1132 BS 4 125 820 800 445 2653 BS 2 75 1020 950 325 4254 BRE 3 114 1000 903 269 1605 BRE 3 70 691 557 4816 BS 2 40 1150 1060 610 -7 ČVUT 4 55 1108 1088 ~1200 925

Test 2 – Column shortening

Structural Integrity Test January, 16. 2003Project teamMr. Martin Beneš Research Student, CTU PragueMr. Luis Borges Research Student, University Coimbra Mrs. Petra Hřebíková Research Student, CTU PragueMrs. Magdaléna Chladná Research Student, Slovak Technical University, BratislavaMr. David Jennings Engineering Technician, BRE WatfordMr. Tom Lennon Supervising Engineer, BRE WatfordDr. David Moore Project Director, BRE WatfordMrs. Aldina Santiago Research Student, University Coimbra Prof. Luis S. da Silva Research Group Member, University CoimbraMr. Paul Sims Project Manager, University Coimbra Dr. Zdeněk Sokol Research Group Member, CTU PragueDr. Jan Pašek Research Group Member, CTU PragueMr. Nick Petty Contracted Technicians, BRE WatfordMr. Jiří Svoboda Res. Group Member, TMV SS, PragueProf. Frantisek Wald European Research Group Leader, PragueMr. David White Project Leader , BRE Watford

)

Tensile membrane action

and robustness of structural steel joints under natural fire

EC FP5 HPRI - CV 5535

Participanting Institutions

Building Research Establishment

Czech Technical University in Prague

Coimbra University,

Technical University, Bratislava

Research Project

ObjectivesTo determine the:- Temperatures in elements and joints Internal forces in the connections Behaviour of the composite Slab

Cardington Laboratory

Structural Integrity Test

Preparation

Temperatures

Connections

Composite slab

Conclusion

Contents

Wall

3 layers of gypsum plasterboard

(15 mm + 12,5 mm + 15 mm)

with K = 0,19 – 0,24 W/mK

Window

9 m x 1,27 m

Fire Compartment

Columns

External joints

1 m of the primary beam

15 mm of Cafco300 vermiculite-cement spray

K = 0,078 W/mK

Protected Members

Permanent 100%

Variable permanent 100%

Live 56%

by sand bags

Mechanical Load

Timber cribs 50 x 50 mm - fire load 40 kg/m2

Fire Load

148 thermocouples 57 strain gauges

Instrumentation

D E

1

2

N

C 1500

1500

1500

1500

1000

222

214

209

204

224

223 225

219

201

215

210

205

220

202

216

211

206

221

203

217

212

207

218

213

208

2250 2250 2250 2250 8000 1000 1000

D E

1

2

N

242

2564

246 249 251

252

247 254

4500 4500

30

00

30

00

245

248 243 253

37 deformations

10 video cameras 2 thermo cameras

Cardington Laboratory

Structural Integrity Test

Preparation

Temperatures

Connections

Composite slab

Conclusion

Contents

Temperatures

Gas 1108 °C in 55 min. (predicted 1078 °C in 53 min.) Beam 1088 °C in 57min. (predicted 1067 °C in 54 min.)

0

100

200

300

400

500

600

700

800

900

1000

1100

1200

0 15 30 45 60 75 90 105 120 135 150

Time, min

Temperature, °C Prediction ENV 1993-1-2

Back of compartmentAverage gas temperture

Front of compartment

Heating

Cooling

Thermo-cameras

Temperature profiles

750,0°C

932,2°C

750

800

850

900

390,0°C

597,1°C

400

450

500

550

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

400,0°C

980,0°C

400

600

800

Cardington Laboratory

Structural Integrity Test

Preparation

Temperatures

Connections

Composite slab

Conclusion

Contents

Fin Plate Temperature Profile

N

E2D2

E1D1

Fin plate

0

200

400

600

800

1000

0 15 30 45 60 75 90 105 120 135 150

Time, min

Tem

pera

ture

, °C

Beam low er f lange (mid-span)

fin-plate (4th bolt-row )

fin plate (1st bolt row )

4th bolt-row

3rd bolt-row

1st bolt-row

Beam w eb

441

444

442

443 445

446

447

448

449

120

100

11

50

460

461

462 9

13

Thermocouples (TC) TC + HSG in Bolt HT Strain Gauges (HSG)

457

455

456

454

15

17

459 19

458

N

E2D2

E1D1

Header plate

0

200

400

600

800

1000

0 15 30 45 60 75 90 105 120 135 150

Time, min

Tem

pera

ture

, °C

Beam low er f lange (mid-span)

Plate (4th bolt-row )

plate (1st bolt-row )

4th bolt-row

1st bolt-row

2nd bolt-row

Header Plate Temperature Profile

Header Plate Strain Gagues

N

E2D2

E1D1

100

11

50

460

461

462 9

13

Thermocouples (TC) TC + HSG in Bolt HT Strain Gauges (HSG)

457

455

456

454

15

17

459 19

458

-360,0

-310,0

-260,0

-210,0

-160,0

-110,0

-60,0

-10,0

40,0

0 15 30 45 60 75 90

Time t [min]

Str

ess

[

N/m

m2]

D2 beam bottom flange

D2 beam web

E2 beam web - estimation

N

E2D2

E1D1

Local Buckling of Beam Lower Flanges

N

E2D2

Con. D2 - D1Con. E2 - E1

Con. D2 - C2

Fracture of End-Plates

N

E2D2

E1D1

Ovalization of holes in the web beam in the fin plate joints

Column Flange Buckling

N

E2D2

E1D1

Beam Web Shear Zones

Cardington Laboratory

Structural Integrity Test

Preparation

Temperatures

Connections

Composite slab

Conclusion

Contents

Concrete slab cracking

D E

1

2

N

10

2030 ~1700

20

~15

00

60

55

90

a b c d e f g h i j k

1

2

3

4

5

6

7

8

9

10

0

1

2

3

3.5

4

4.5

5

6

7

9

12

15

0.00

2.25

4.50

6.75

9.00

-100-90

-80

-70

-60

-50

-40

-30

-20

-10

0

Slab deflection after testDate: 23th January 2003

-10.0-0.0-20.0--10.0-30.0--20.0-40.0--30.0-50.0--40.0-60.0--50.0-70.0--60.0-80.0--70.0-90.0--80.0-100.0--90.0

Concrete slab deformation

Residual deformation max 925 mm

Fracture of end plates Elongation of holes in fin plates Integrity of composite slab Collapse of structure not reached

Mechanical load 56%Fire load 40 kg/m2

Conclusions

Thank you for your attention