1. Fire Testing of an Earthquake Damaged R.C. Frame Presented by: U.K. Sharma/Pradeep Bhargava Under UKIERI Project being Jointly Investigated by: Indian Institute of Technology Roorkee University of Edinburgh, U.K. Indian Institute of Science Bangalore

2. INTRODUCTION Major earthquakes have been followed by multiple ignitions San Francisco, 1906 Tokyo, 1923 San Fernando, 1971 Northridge, 1994 Hanshin (Kobe), 1995 Izmit (crude and naptha tanks), 1999

3. Fire Following Earthquake Probability of Ignition is high. Toppled furniture, electrical malfunctioning and movement of hot equipment. Active and passive systems may be damaged by earthquake. Probability of prompt fire service attention is much lower.

4. Due to rapid urbanisation, there is an increasing risk of Fire Following Earthquake (F.F.E.) events. FFE events have added a new dimension to disaster management and call for substantial research effort to address the relevant challenges. The collaborative research project between the University of Edinburgh, Indian Institute of Technology Roorkee and the Indian Institute of Science Bangalore proposes to conduct large-scale tests to investigate the behaviour of (earthquake-induced) pre-damaged R.C. frames in fire.

5. Simulated seismic damage Fire loadingAftermath 1 Displacement beyond peak lateral force 900 o C -1000 o C* Residual lateral capacity test* 2None900 o C -1000 o C for 1 hr Residual lateral capacity test 3 Moderate (30% of the displacement corresponding to peak lateral force)† 900 o C -1000 o C for 1 hr Residual lateral capacity test 4Severe (70% of the displacement corresponding to peak lateral force)† 900 o C -1000 o C for 1 hrResidual lateral capacity test Summary of the proposed frame tests * for as long as considered safe (maximum 1 hr) †applied incrementally and cyclically

6. Plan and elevation of the frame sub-assemblage proposed to be tested

7. Detailing of the frame sub-assemblage Detailing of a typical beam

8. Detailing of the column and footing

9. Detailing of the slab

10. F Brick masonry infill 115 thick 3000 c/c both ways All Columns- 300x300 mm Fire compartment All Beams-230x230 4300 both ways Beam Column Framing plan of the frame sub-assemblage 120 thick slab

11. Test set-up configuration Brick masonry infill wall in perimeter

12. Nominal location of thermo-couples and strain gauges INSTRUMENTATION

13. Nominal location of L.V.D.T.’s

14. Nominal location of thermocouples and strain gauges in the slab

15. Analytical modeling of the frame sub-assemblage The sub-assemblage was designed as part of a 4-storey moment resistant R.C frame located in seismic zone IV of IS 1893 (Part 1):2002. Ductile detailing was carried out as per IS 13920. (a) (b) Detailing of a typical beam, (a), and a column, (b). When calibrated against the Eurocode 8, the design was found to be sufficiently ductile. However, a plastic analysis of the sub-assemblage indicated that the first hinge formed in a column instead of a beam

16. Finite element model of the frame sub-assemblage showing hinging in columns Col. bars=8-12ø Beam bars=2-12ø+3-16ø at top and bottom

17. Col. bars=8-20ø Beam bars=3-16ø at top and bottom Plastification at joint Beam hinging The modification of detailing in the beams and columns resulted in a more Desirable pattern of hinging

18. Analytical load-displacement relationships (a) SAP frame model (b) ABAQUS finite element model Comparison of the predicted load-displacement relationships for the frame sub-assemblage from SAP and ABAQUS

19. Mock Fire Tests Front elevation of the fire compartment for the mock tests Thermocouple tree Fuel tray

20. Post flash-over phase of the compartment fire

21. Time-temperature relationships for the fire compartment near the centre of the back wall and opposite to the opening

22. Strong floor – reaction wall system Detailing of rebars in the strong floor, dowels for the footing can also be seen

23. Freshly cast concrete in the strong floor, dowels for the orthogonal reaction walls can be seen in the background

24. Erection of the reinforcement cage for the reaction wall. Pipe sleeves for anchoring the loading jacks can also be seen

25. The quasi-static loads shall be applied with a pair of these 500 kN capacity double acting hydraulic jacks

26. Target displacement Time Earthquake loading simulation Proposed (quasi-static) loading history for the frame sub-assemblage

27. OpenSees analysis of cyclic loading (plotted for 1 column)

28. Maximum base shear plot from OpenSees analyses

29. Another Aim of the Project: Stress-Strain Models for Pre-Damaged Materials Stressed Tests Unstressed Tests Residual Tests Present Models Stress – strain relationships for concrete at elevated temperature

30. Structural Modelling Round-robin Exercise The challenge: – To model blind the behaviour of a concrete structure during fire following earthquake Aiming to – Identify strengths and weaknesses of modelling capabilities If interested contact Martin Gillie: – m.gillie@ed.ac.uk m.gillie@ed.ac.uk – www.see.ed.ac.uk/~s0458490/UKIERI/

31. Predictions Horizontal and vertical deflections during the earthquake loading Temperature of the rebar during heating and cooling Horizontal and vertical deflections during heating and cooling

32. Dates Competition announced June 2010 Structural data on website Summer 2010 Date of test Late Summer 2010 Confirmation of required predictions Day after test Submission of predictions 1 March 2011 Results conference Spring 2011

33. THANK YOU