Munich Fire Tests on Membrane Action

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1 Munich Fire Tests on Membrane Action Dipl.-Ing. (FH) Martin Stadler Prof. Dr.-Ing. Dipl. Wirt.-Ing. (NDS) Martin Mensinger Technische Universität München Martin Stadler 1

2 Research Project Utilisation of Membrane Action for Fire Design of Composite-Beam-Slab- Systems (Nutzung der Membranwirkung von Verbundträger-Decken-Systemen im Brandfall) Main objectives: - Enable membrane action in Germany - Clarify remaining issues Martin Stadler 2

3 Remaining Issues Adjustment to German regulations Load bearing mechanism: Pure membrane action? Bending? Combination of bending and membrane forces? Failure criteria: Rupture of reinforcement? Failure of edge beams? Behaviour of the edge beams between two slab panels Large cracks and rupture of reinforcement may influence composite action. Can every slab panel really be considered separately? Martin Stadler 3

4 Solution Methods 1. Numerical simulations - Comprehension of the load bearing mechanism - Parameter studies 2. Experimental investigations - Verifying the theoretical approaches 3. Analytical investigations - Simple methods for design 4. Preparation for Application - Application supports - Worked examples Martin Stadler 4

5 Experimental Investigations Martin Stadler 5

6 Test Arrangement Office building Typical materials, dimensions and beam arrangement in Germany Two slab panels with intermediate beam Loading according to Eurocodes (mechanical and thermal) Design for ambient temperature with high utilization factors Protection of edge beams R 60 with intumescent coating Martin Stadler 6

7 Specimen 1 lattice girder precast slab water based coating (Rüttgers Organics) Specimen 2 profiled steel sheeting composite slab (Holorib) solvent based coating (Sika) Martin Stadler 7

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15 Additional Dead Load Additional permanent load and live load of an office building in fire situation q = 2.1 kn/m² Martin Stadler 15

16 Natural Fire with Wood Cribs Thermal load: 90% fractile of an office building according to Eurocode 1 q f = 584 MJ/m² Martin Stadler 16

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18 First Test Performed 7 th July, Second 3 rd September 2010 Martin Stadler 18

19 Temperatur [ C] Gas Temperatures close to Standard Fire Curve Zeit [min] ETK gem. Temp. Brandraum Martin Stadler 19

20 temperature [ C] Gas Temperature Simulation with OZone ISO834 average measured OZone predicted OZone corrected time [min] Martin Stadler 20

21 Temperatur [ C] Temperatures in Slab ETK gem. Temp. Brandr. 0 mm 30 mm 60 mm 90 mm 120 mm Zeit [min] Martin Stadler 21

22 Temperatur [ C] Unprotected Secondary Beam ETK gem. Temp. Brandr. Unterflansch Steg Oberflansch Zeit [min] Martin Stadler 22

23 Temperatur [ C] Protected Edge Beam ETK gem. Temp. Brandr. Unterflansch Steg Oberflansch Zeit [min] Martin Stadler 23

24 Temperatur [ C] Protected Intermediate Beam ETK gem. Temp. Brandraum Unterflasch Steg Oberflansch Zeit [min] Martin Stadler 24

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27 Displacement [mm] Vertical Displacements Time [min] V6 larger slab V7 intermediate edge beam V8 smaller slab Martin Stadler 27

28 Large Crack close to Intermediate Beam Test 1 Loss of Criteria E and I Martin Stadler 28

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31 Crack Development Uncracked concrete Principal stresses, top layer of slab tension compression Martin Stadler 31

32 Crack Development Bending hinge above intermediate beam Principal stresses, top layer of slab tension compression Martin Stadler 32

33 Crack Development Ruptured reinforcement Principal stresses, top layer of slab tension compression Martin Stadler 33

34 Small Bending Crack above Intermediate Beam Test 2 No Loss of any Criteria REI Martin Stadler 34

35 Bolt Failure Martin Stadler 35

36 Spalling at RC Columns Martin Stadler 36

37 Thanks to our Supporters Martin Stadler 37