FIRE SAFETY IN CONSTRUCTION: GETTING IT RIGHT

Transcription

1 FIRE SAFETY IN CONSTRUCTION: GETTING IT RIGHT Prof Ali Nadjai: Director of FireSERT BEng(H), MSc, PhD, Ceng, MIStructE, MIFireE, PGCUT ulster.ac.uk Slide 1

2 INTRODUCTION Canada USA FireSERT Sweden Russia Europe China North Africa Middle East Qatar Abu Dhabi Oman South America Hong Kong Singapore JAPAN South Africa Australia Firesert: Centre of Excellence

3 Firesert: Centre of Excellence Slide 6 Provide an internationally competitive research base for fire safety science Extend/develop the knowledge base for fire safety engineering Disseminate knowledge to the widest possible audience To develop and deliver higher technical fire safety education and training programmes Support industry and Innovation

4 INTRODUCTION Fires are recognised as one of the major threats of life and property in many countries. The primary goal of fire protection is to preserve life safety. A second goal is to protect property and safeguard the environment. Relatively Young discipline rapidly emerging field Broad and interdisciplinary address complex problems Economic impact of fire in buildings has been estimated at ~1% of GDP a vast sum now exceeding 10 billion annually

5 INTRODUCTION Buildings are at the centre of our social and economic activity. Not only do we spend most of our lives in buildings, we also spend most of our money on buildings. The built environment is not only the largest industrial sector in economic terms, it is also the largest in terms of resource flow.

6 Previous Fire Disasters Building Fires Compartmentation not well respected Windsor Building Madrid, 12 February 2005

7 The next day... Insurance payout 300 millio 2 metro lines closed 30,000 people unable to get to work Olympic bid damaged

8 Taegu Subway Fire Disaster 13 th, FEB, 2003 Arson in the train Fire Propagation Taegu St. Chungangro St Train approach Chungangro St Fire propagation over train 8

9 Previous Fire Disaster WOUNDED DEAD 9

10 Seoul 10 th February 2008, 610 year old landmark top national treasure 10

11 Tunnel Fires - Explosive Spalling of Concrete A Warehouse without Sprinklers Matalan, Birmingham 2 March 2006 loss in business turnover Job losses problems with clients and customer if supply cannot be fulfilled due to fire damage. Channel Tunnel (UK-France, 2008)

12 Previous Fire Disaster Shanghai high rise residential building, persons died and over 50 injured

13 Previous Fire Disaster The rate of fires resulting in extensive fire spread involving combustible exterior wall systems is gradually increasing due to the of energy efficient but combustible materials and the consequences of such fires are very large especially for those smart and green high-tech buildings. Saif Belhasa building fire, Tecom 2012 (left) & Tamweel Tower fire 2012 (right). Shanghai Fire (left) and CCTV Tower, Beijing fire (right).

14 Previous Fire of Disaster what is clear is that there is a need to better understand how façade systems behave in situ, during fires and how the combination of decoration and insulation materials,

15 Legal liabilities Regulatory Reform (Fire Safety) Order Responsible person Fire Risk Assessment of general fire precautions Competent person Enforced by Fire Authority Problems: Qualifications? Skills? Competency Evaluation?

16 Research is required to improve Buildings fire safety Lessons from real fires in real buildings Full (or large) scale fire tests Well instrumented and designed small scale fire tests Materials investigation Use of smart technology Robustness of building regulations More robust and safer designs Validate d computer software Validated design methods Allows optimum design to be determined taking into account life safety, financial impact and environmental issues

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18 Challenge Fire safety Economic impact of fire in buildings has been estimated at ~1% of GDP a vast sum now exceeding 10 billion annually

19 Mechanism of working Government EUROPEAN FUNDING EPSRC FUNDING Fire Research Fire testing Fire Guidance and design Software development Training (CPD) University/ Institute Industry Commerce & Marketing Research Development Design Rules

20 Role of the University of Ulster to FireSERT Supporting the Next Generation Leaders for Fire Safety and Clean Regeneration Energy Application Technology Developing Qualified Human Resources Developing high level research oriented universities Select & focus Specialization in Future technologies Producing next generation scholars Continuous support for master course, PhD, and advanced-level researchers Improvement and assistance Improvement and assistance of education program Top class experts Industry-academic collaboration and international cooperation

21 How Fire spread in Long Corridor Enclosure and Facades The enclosure is made of fireboard (4 cm thickness). Facade 300 cm 155 cm 50 cm Propane burner 50 cm - Side view - - Front view - 4 Opening dimensions (Width Height) : m 2, m 2, m 2, m 2

22 Flame moving horizontally from the back (location of the burner) towards the opening then ejected (i.e. external burning). HRR profile Temperature profiles 40 Ejected flame Theoretical HRR Actual HRR 1500 A 0 H 0 1/ Fire Growth Ventilation-controlled stage HRR = 1500 A 0 H 0 1/2 Steady-state (Maximum HRR) Flame comes out HRR (kw) Ventilation-controlled Growth (Fuel-controlled) Steady State Decay Temperature (C) Box F Box E Box D Box C Box B Box A Time (min) Time (min)

23 Temperature Profiles EXP. DATA: No external burning FDS 5.3.0: External burning FDS 4.0.7: External burning

24 How people Behave in fire and modelling fire evacuation

25 How real building failed in fires a) Early stages, b) spreading in the northwest side, c) extended to entire floor levels

26 How to use FEM to Analyse failure mechanisms 26

27 Actions on structures exposed to fire EN

28 Structural Fire Safety Engineering vs. Classification

29 Actions on structures exposed to fire EN

30 Natural Fire Safety Concept 1- Implemented in Eurocode 1 Fire Part 2- Some National Fire Regulations include now alternative requirements based on Natural Fire

31 List of needed physical parameters

32 Characteristics of the fire compartment

33 Characteristic of the Fire for different buildings

34 Fire load density

35 Rate of Heat Release Curve Stationary State and Decay Phase

36 Rate of Heat Release Curve Stationary State and Decay Phase

37 How Fire Engineers interact with other members Research Structural Knowledge Analysis / Calculations Structural Fire Specialist Experiences Architects Structural Engineer Fire Engineer Code of practice Code of practice Solution

38 Simplified Fire Models

39 Fully Engulfed Compartment : Parametric Fire

40 Case study 1: Localised Fire in Large Compartment

41 2. State-of-the-art and reason for the project Reason for the project Annex C of EN : Flame not impacting the ceiling Flame axis Annex C of EN : Flame impacting the ceiling concrete slab H L f beam θg Y z D Y = Height of the free zone How to calculate the temperature in a column subjected to the radiation of the fire? 41

42 Localised Fire: Annex C of EN

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45 DESIGN OF COLUMNS SUBJECT TO LOCALISED FIRES The effects of a local fire result in four distinct regions, each of which receives different levels of heat flux. These regions can be split as follows: 1- Outside the fire 2- Inside the fire 3- Inside the fire, in the smoke layer 4- Outside the fire, in the smoke layer It assumes that the shape of the fire on the ground is circular and is intended for localised fires that do not exceed a diameter of 10 m and a heat release rate of 50 MW.

46 Analytical method and validation Modelling of the flame Step 1: The surface of the fire is transformed into an equivalent discus Step 2: The evolution of Heat Release Rate is calculated according to EN Annex E (growing phase, plateau, decaying phase) Step 3: The flame length L f is calculated by application of EN Annex C Step 4: The action of the fire is represented by a virtual solid flame, conic or cylindric, defined by D eq and L f Q (or HRR) Cylinder model Cone model paraboli c constant HRR max (fuel or ventilation controlled) linear time L f D eq D eq 46

47 Analytical method and validation Simplified model Sub-division of the flame into cylinders and rings If the flame does not touch the ceiling (L f < H ceiling or no ceiling) If the flame does touch the ceiling (L f > H ceiling ) 47

48 Analytical method and validation Simplified model Model validation based on Ulster tests (and FDS modelling) Case 1a 1 pan D = 0.7 m Gauges at 0.5/1.8 m Case 1b 1 pan D = 0.7 m Gauges at 1.0/1.6 m Gauge location Height Distance Experime nt mean FDS Simulatio n Cylinder flame 48 Conic flame m m kw/m² kw/m² kw/m² kw/m²

49 Case 2: Fire Protection Water mist suppression research Improving water mist performance using chemical additives Various additives testing Novel small compartment experimental set-up Low pressure water mist systems Feasibility studies aimed at improving system performance

50 Case study 3: Design Safe structures Avoid and eliminate catastrophic collapse. The compartment is designed to represent a modern open plan office15x 9 m. In this test, both the perimeter beams and the columns are protected (including connections) with the internal beams unprotected. Sponsor: EU 1.6 Million (2007- Oct 2010)

51 Fire Test

52 RFS-PR-06102: Fire Resistance of Long Span Cellular Beams Made of Rolled Profiles (FCEB) Starts: 28 August 2007 Ends: 31 July 2011 Value (Euro): 1.6 Million EUROCODE DESIGN Engineering Physical Science Research Council(EPSRC): EP/F001525/1 Performance of Cellular Composite Floor Beams under Severe 2008 end April 2011 Fire Conditions, Value ( ) 408,000 Starts: May

53 New strength mode in the Design Code 1,0 Reduction factors (x 1E-3) 0,8 0,6 0,4 0,2 k Ea,θ k ap,θ k ay,θ 0, Temperature ( C) 1 k ay,θ 0,8 Reduction factors 0,6 0,4 0,2 k Ea,θ k ap,θ Temperature ( C)

54 MACS+ Design Example Gravity design case MACS+ membrane design case Fire load design case 54

55 02 ASD Westok - Projects

56 Low energy, lightweight building components and thermally effective facades for zero carbon buildings (ENERGY-BUILD) Past Facade Fires Castledawson Fire Test conducted by Nadjai 2010

57 Design Guide Membrane Action of Composite Structures in Case of Fire Ali Nadjai, Olivier Vassart, Bin Zhao

58 Experimental Investigation of Localised fire on Glazing Facades systems having different orientations Prof A NADJAI Vertical Glazed Facade Test Vertical Glazed Facade Inclined Glazed Facade Test Inclined Glazed Facade Vertical Glazed Facade Model Stresses Inclined Glazed Facade Test Inclined Glazed Facade Model Stresses

59 Pre Test & Post Test Pictures Post Test TGA TGA Results Graphs Intumescent Paint Sample Precision Weighing Post Test DSC DSC

60 Low energy, lightweight building components and thermally effective facades for zero carbon buildings (ENERGY-BUILD) Scientific Material Analysis Resin Sample TGA Test Equipment DSC Test Equipment TGA Resin Results Graph DSC Resin Results Graph Time Temperature Sample Mass Minutes C % TGA Resin results Table Time Temperature Power Minutes C mw DSC Resin Results Table

61 UNIQUE: FROM NANOSIZE TO 20 MW FIRES NANOCOMPOSITES INTRINSIC FLAMM. PROPERTIES (TGA, FTIR, MDSC, UNIV. FLAMM. APPARATUS) LARGE SCALE (20MW) MATERIAL AND CFD MODELLING Solid Phase TGA, DTA, DSC, ATR Milligram size samples thermal and toxicity analysis Major projects: FIRENET (EU) 2M FAÇADE FIRES (EPSRC, Japan) 200K PREDFIRE NANO (EU) Eu3M Industrial R&D, Brominated Substitutes Eu4M

62 Fire Station Risk Level 3 Technique of predicting Fire and suppression root Risk Level 2 Risk Level 1 Early Fire Suppression equipment Latest Fire Detection technique

63 Thank you for your attention!!!