Modelling of thermal effects of fires in buildings made of wooden structures on neighbouring objects

Introduction. When designing and constructing wooden buildings, regulatory documents stipulate a number of restrictions due to their low fire resistance. Fire breaks (distances) for such buildings are maximum, and an increase in their number of floors will lead to their additional increase. In this regard, it seems reasonable to conduct research in terms of assessing the optimal fire breaks to limit the spread of fire in wooden buildings to neighbouring facilities.

Aims and objectives. The aim of this work is to study by field modelling the peculiarities of fire behaviour of wooden structures to determine the quantitative characteristics of heat flows to neighbouring protection facilities for the selection of safe fire separation distances.

Research methodology. To achieve the purpose of the study, field modelling of fire dynamics using the FDS computer software package was used. During the simulation, the values of temperatures and heat fluxes to neighbouring objects from fires in wooden buildings were obtained.

The results and their discussion. As a result of modelling of fire development in wooden buildings of different number of floors, values of the intensity of thermal radiation on neighbouring objects were obtained, including taking into account the wind load. The results of the calculations made it possible to develop proposals for the application of the data obtained in the development of sound regulatory requirements for fire safety.

Conclusion. It is shown that in case of fires in buildings with structures made of unprotected wood, with an increase in the number of floors, an increase in thermal effects on neighbouring objects is observed. In the presence of wind in the direction of a neighbouring object, the thermal effect also increases. When assessing safe distances, the possibility of combined exposure to radiant and convective flows should be taken into account. In order to comply with the current regulatory values of fire-fighting distances, it is necessary to increase the fire resistance of wooden buildings by increasing the fire resistance limits and reducing the fire hazard classes of load-bearing and enclosing building structures.

1. Khasanov I.R. Features of fire safety of buildings of wooden structures. Pozharovzryvobezopasnost/Fire and Explosion Safety. 2016; 25(11):51-60. DOI: 10.18322/PVB.2016.25.11.51-60 (rus).

2. Gordienko D.M., Abashkin A.A., Khasanov I.R., Zuev S.A. Regulatory regulation in the field of fire safety of multi-­storey buildings made of wooden structures. Fire Safety. 2023; 1:59-67. DOI: 10.37657/vniipo.pb.2023.110.1.006 (rus).

3. Östman B. National fire regulations for the use of wood in buildings : worldwide review 2020. Wood Material Science and Engineering. 2021; 17(1):1-4. DOI: 10.1080/17480272.2021.1936630

4. Östman B., Brandon D., Frantzich H. Fire safety engineering in timber buildings. Fire Safety Journal. 2017; 91:11-20. DOI: 10.1016/j.firesaf.2017.05.002

5. Aseeva R., Serkov B., Sivenkov A. Fire behavior and fire protection in timber buildings. 2014; 290. DOI: 10.1007/978-94-007-7460-5

6. Albert C.M., Liew K.C. Recent development and challenges in enhancing fire performance on wood and wood-based composites : а 10-year review from 2012 to 2021. Journal of Bioresources and Bioproducts. 2024; 9(1):27-42. DOI: 10.1016/j.jobab.2023.10.004

7. O’Connor D.J. The Building Envelope: Fire Spread, Construction Features and Loss Examples. SFPE Handbook of Fire Protection Engineering, 5th Ed. Society of Fire Protection Engineers, 2016; 3242-3282. DOI: 10.1007/978-­1-4939-2565-0_86

8. Roitman M.Ya. Fire prevention in construction. Moscow, VIPTSH of the Ministry of Internal Affairs of the USSR, 1975; 256. (rus).

9. Romanenko P.N., Koshmarov Yu.A., Bashkirtsev M.P. Thermodynamics and heat transfer in firefighting. Moscow, VIPTSH of the Ministry of Internal Affairs of the USSR, 1977; 415. (rus).

10. Ryzhov A.M., Khasanov I.R., Karpov A.V., Volkov A.V. et al. Application of the field method of mathematical modeling of indoor fires : methodological recommendations. Moscow, VNIIPO, 2002; 35. (rus).

11. McGrattan K., Miles S. Modeling fires using Computational Fluid Dynamics (CFD). SFPE Handbook of Fire Protection Engineering, Fifth Edition. Society of Fire Protection Engineers, 2016; 1034-1065. DOI: 10.1007/978-1-4939-2565-0_32

12. McGrattan K., McDermott R., Weinschenk C., Overholt K. et al. Fire dynamics simulator user’s guide: NIST Special Publication 1019. Sixth Edition. Gaithersburg, National Institute of Standards and Technology, 2013; 262.

13. Lu W.L., Cheng J.X. Numerical simulation analysis of fire in ancient building burning temple. Fire Science and Technology. 2012; 4:290-293. DOI: 10.3969/j.issn.1009-0029.2011.04.006

14. Enaru I., Chereches N.-C., Hudișteanu S.-V., Țurcanu E.-F. et al. Numerical simulation evaluation of fire spreading in a building using Fire Dynamics Simulator (FDS). Journal of Applied Engineering Sciences. 2023; 13(26):65-72. DOI: 10.2478/jaes-2023-0009

15. Nguyen H.T., Abu-Zidan Y., Zhang G., Nguyen K.T.Q. Machine learning-based surrogate model for calibrating fire source properties in FDS models of facade fire tests. Fire Safety Journal. 2022; 130:103591. DOI: 10.1016/j.firesaf.2022.103591

16. Misic N., Dusica N., Pesic J. Simulation of fire radiative heat flux through compartment openings using FDS. 24th International Conference on Fire Protection. Ostrava, 2015; 380-383.

17. Khasanov I.R., Zuev S.A., Abashkin A.A., Zueva A.S. Fire-fighting distances from surface parking lots to residential buildings. Fire Safety. 2022; 1(106):57-66. DOI: 10.37657/vniipo.pb.2022.75.67.005 (rus).

18. Huai C., Xie J., Liu F., Liu J. Experimental and numerical analysis of fire risk in historic Chinese temples: а case in Beijing. International Journal of Architectural Heritage. 2021; 16(12):1844-1858. DOI: 10.1080/15583058.2021.1916648

19. Zhang F., Shi L., Liu S. CFD-based framework for fire risk assessment of contiguous wood-frame villages in the western Hunan region. Journal of Building Engineering. 2022; 54:104607-104607. DOI: 10.1016/j.jobe.2022.104607

20. Janardhan K., Hostikka S. Predictive computational fluid dynamics simulation of fire spread on wood cribs. Fire Technology. 2019; 55(4):2245-2268. DOI: 10.1007/s10694-019-00855-3

21. Hayajneh S., Naser J. Fire spread in multi-storey timber building, a CFD Study. Fluids. 2023; 8(5):140:17. DOI: 10.3390/fluids8050140

22. Zhao X., Wei S., Chu Y., Wang N. Numerical simulation of fire suppression in stilted wooden buildings with fine water mist based on FDS. Buildings. 2023; 13:207. DOI: 10.3390/buildings13010207

23. Aseeva R.M., Serkov B.B., Sivenkov A.B. Burning of wood and its fire-hazardous properties : monograph. Moscow, Academy of GPS of the Ministry of Emergency Situations of Russia, 2010; 262. (rus).