WG 1: Fire Engineering V. Strategy and guidelines for damage prevention Fire design in Europe Tampere University of Technology, Finland Cost C26 Conference 1
Contents of the presentation: In what extent the performance based fire design and especially Eurocodes for fire design are used in Europe? Case study of fire loads for the performance based fire design in one rather large project, sport centre built in Helsinki, Finland Cost C26 Conference 2
Description Europa has started to use Eurocodes EN standards include principal and application rules for fire design of buildings including also performance based design Scope of this study: What is the state of art for applying the EN standards for fire? And, what is the state of art in performance based fire design? For which kind of applications exist experiences? These were the main questions sent to the members of COST C26 during spring 2008 Total 12 answers were got from 10 countries. Three different answers were got from UK The summary of the results follows Cost C26 Conference 3
National fire codes include performance based fire design Czech, UK, Finland, Hungary, Italy Possible: Belgium (if agreed by Ministry of Interior), France (partially) Use of fire Eurocodes in Europe Year 2008 means typically: expected to be published France is waiting for shifting from ENV to EN (in 2008) UK has used the final Eurocodes for the longest time Cost C26 Conference 4
The question dealing with the use of EN 1991-1-2, Annexes (fire loads) gave a wide scatter of answers, meaning: There exist very many ways to define the fire loads in buildings in Europe, allthough EN standards are used! Examples (details in Datasheet Nro 8/COST C26, WG 1): Five countries do not allow the use of the Annex F dealing with equivalent time of fire exposure. There are limitations to use of Annex E (fire load densities), and one for Annex C (localised fire). In two countries the Annex A (parametric temperature-time curves) is allowed to be used only in the preliminary design stage. In France the use of Annexes C and D need to have a peer review of the assessment report according to clause 15 of decree 22 March 2004. In these 10 countries ONLY the Annexes B (thermal actions for external members simplified calculation method) and G (configuration factor) are accepted as they are. Cost C26 Conference 5
The detailed question dealing with the EN 1991-1-2, clause 4.3.1(2) dealing with the representative values of variable actions in fire: ψ > ψ 2 = 0 Just to remember: 1 ψ 2 and often for e.g. wind load Italy, Romania: ψ 2 France, Portugal (Spain, Estonia, Slovenia from Difisek+): ψ1 ψ 2 UK: for EQU and for STR Belgium (Netherlands, Luxembourg):, but for wind ψ 2 ψ 2 ψ 1 ψ 1 Czech:, but for wind and snow ψ 2 1 Finland:, but for wind, snow and ice ψ ψ 1 This means that there exist e.g. wind loads in fire in almost every country in Europe => You must read carefully all the NA s when exporting products => You must look at national codes and national rules to define fire load details in many countries in Europe when applying Eurocodes Cost C26 Conference 6
However: Faculty of Built Environment, Dept. of Structural Eng. Performance based fire design has been used to the following tasks: fire resistance of structures, evacuation calculations, smoke control, risk analysis, optimization the fire protection requirements in structures, studies of local fires, studies of external flames, studies of equivalent times of exposures, demonstration of adequate fire fighting provisions, demonstration of extended travel distances, demonstration of an acceptable standard of safety in complex buildings with large numbers of people and/or large open spaces. Cost C26 Conference 7
Projects: shopping centres, office buildings, airports, hospitals, residential buildings, stadiums, music halls, underground facilities, industrial buildings, historical buildings, high rise buildings, car parks, libraries, churches, monumental buildings, warehouses, cruiser ships. Typically in large projects, BUT increasingly also in other projects Examples Fire resistance, evacuation: Terminal Mošnov, (Czech) Fire resistance: Storage hall Mnichovo Hradiště, (Czech) All the major shopping centres in the Helsinki region as well as in other parts of Finland, Office buildings (e.g. Nokia headquarters, the Sanomatalo in Helsinki, Finland), Bucharest Tower Center Evacuation calculations: East London Line Stations, BSF School, Birmingham, Smoke flow analysis: Feature Tower at the ADNEC site, Abu Dhabi, Larnaka Airport, Cyprus, Structural fire protection calculations: River Quarter II Residential Building, Sunderland, Sports Pavilion, Bradford Grammar School, Thermal radiation analyses: Bold Lane Development, Derby, Finzel s Reach, Residential Re-development, Bristol, Heathrow Terminal 5, New Air Traffic Control Tower at London Heathrow Airport, Redevelopment of the historic Spitalfields Market in Central London, New research building for Queen Marys, University of London, Project Emma, HMS Nelson, Portsmouth, Alnwick Castle, Lloyds Registry of Shipping, School of Slavonic and East European Studies, University College London, Queen Mary s New School for Dentistry and Medicine. Cost C26 Conference 8
Need of approval of third part for performance based fire design Cost C26 Conference 9
Requirements of documentation Cost C26 Conference 10
Programs used for performance based fire design Cost C26 Conference 11
Problems when applying performance based fire design Lack of experience and confidence of authorities How to define design fires in some cases Lack of design tools Lack of education (at very low level in 10 countries involved) Some progress have started e.g. in Chech, France, Poland, Finland Special certificates required for designers by the authorities in some countries enforce the educational institutes to come to this area in the future! Cost C26 Conference 12
Case study: Salmisaari Sport Centre, completed 2009-2010 in Helsinki, Finland Dimensions of the building: Length 136 m Width 35 m Height 36 m Four stories, each 8-10 m high Each story: 30 m wide space supported by 30 m span trusses In this project: Performance based fire design for these trusses Cost C26 Conference 13
Trusses: Innovative solution used in buildings where large columnfree spaces required Columns: Composite steel tubes filled with reinforced concrete Cost C26 Conference 14
Project organization for fire design: 1. Fire engineer, builder and local fire authorities defined fire scenarios 2. After that fire engineer defined details for fire cases 3. Builder and fire authorities approved these 4. Then fire cases were simulated using FDS including control points to get temperatures of steel members in fire 5. The temperatures were delivered to the structural engineer, who checked the structures 6. The structural authorities checked and approved the fire design of trusses In the paper: Details of steps 1, 2 and 4 are given. Cost C26 Conference 15
Design fire load definition: EN 1991-1-2, Annex E1 not possible to use in Finland Project specific definition of design fire loads What should be taken into account when defining design fire loads: Fire activation risk due to size and occupancy. In this case: Tillander at al, 2009 Active fire fighting Automatic fire supression, Sprinkler defects only, see paper Automatic fire detection, not taken into account in this case Manual fire suppression, not taken into account in this case Characteristic fire load density National fire load classifications by occupancies By conductiong fire load survey using both analysis and synthesis of experimental data as well as modelling and fire simulation Results are given in the paper for this case Cost C26 Conference 16
We ended up in this case to three categories of design fire loads: Global and local fires defined to all categories Categories: Intended use of spaces (for 50 years period) E.g. bowling, martial arts, restaurant Special use of spaces (for 50 years pediod) E.g. ice resurfacing machine fire in icehall or Plastic slide fire in adventure place for children Abnormal use of spaces (occurrence assumed once a month) E.g. stage or stand fires Cost C26 Conference 17
Examples of design fires: Local fires a) for sport areas (15 MW) b) for restaurants el al (25 MW) Cost C26 Conference 18
Examples of design fires: Global fires Cost C26 Conference 19
Modeling of local fire for FDS program Assumed that fire starts just below the broken Sprinkler Cost C26 Conference 20
Example of special use fire: Ice resurfacing machine fire Our design fire Cost C26 Conference 21
After definition of all design fires we put those to the product model of the building (Integrated fire design system, see Heinisuo et al, Prague, 2009) Controls: Computational grid sizes (error estimations, fit to multiprocessing) Modeling of fires and obstacles (structures) to fit to the computational grids (rounding system of FDS!) Output of temperatures Then we transfer the building and fire entity data to FDS program After that simulations of all the parts of the building Then temperatures to the structural designer More details in the paper Cost C26 Conference 22
Example of special use fire: Ice resurfacing machine fire Cost C26 Conference 23
Conclusions Performance based design not only for exit design (evacuation, smoke control), but also for resistance of structures in fire Not only large projects, but increasingly for all projects National rules still used in fire design, with Eurocodes same rules all around Europe Not yet reality, hopefully some day! E.g market fires similar all around! Challenges to use preformance based fire desing: Lack of experience Lack of confidence by the authorities Checking the design calculations, third part approval GOOD practice Lack of education, some progress have been started in some countries Research activity is at rather high level, knowledge transfer from research to practise! All features of computing have not yet realized in practical projects Case studies and experiences from real cases needed to get experiences Still too much lost lifes in fires! Cost C26 Conference 24
Thank you Questions? Cost C26 Conference 25