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A series of scientific data and preliminary conclusions on the fires that hit Attica on July 23 gave the Department of Geology and Geoenvironment and the postgraduate program "Strategies for the Management of the". Environment, Disasters and Crises "of the University of Athens
The data are presented in a special bilingual issue, prepared in collaboration with the National Observatory of Athens, in the purpose of immediately informing the international scientific community and
As research and data collection are still ongoing, some of these findings are subject to change. However, at first, scientific research shows that:
1. The phenomenon is a typical fire case in an urban wildland interface, which acted like an active face fire. These areas are among the areas with the highest probability of human casualties in the world, as well as in the Greek zone. There are many cases of such areas in Greece.
2. During the fire, strong westerly winds, speeds at locations and intervals of over 90 km / h (between 17:00 and 21:00 on 23/7/18), as well as their interaction with the topography of the area, played a very important role in the rapid transmission of fire and its propagation at lower altitudes (downward propagation)
3. The rapid spread of fire has contributed significantly to minimizing the available reaction time, which has contributed to the large number of casualties
4. On the basis of systematically badyzed testimonies, it appears that the population close to the beach, at least in some places, received information that the fire was approaching the coast, not by a operator, but by evacuees. the most western part of the Mati settlement. This shows that the population had almost zero time between the awareness of risk and the decision of the reaction
5. Above all, it is considered the particular urbanism of the colony, which acted as a "trap" for the people who tried to escape. Some of its important features were: narrow streets, many dead ends, particularly long building blocks, no possibility of lateral leakage, lack of concentration areas (eg square, stadium). The role of the escape route could be parallel to the shoreline, but wide, to adjacent settlements
6. Field research has identified some weaknesses in buildings with sensitive points on the roof, frames, environments and other places. At the same time, a large number of buildings were totally destroyed.
7. In first estimate, it was observed that houses and buildings that were raised or with floors, with less damage to the ground and underground, typical of a crown fire, were observed. At the same time, significant differences were observed between buildings in terms of impacts likely to be badociated with building materials and adjacent vegetation.
The first results, based on systematically badyzed testimonies, show that the colony's escape attempt was disorderly, did not constitute an organized movement of citizens, provoked congestion due to the high concentration of population and the panic. In addition to the inhabitants there were visitors / tourists, a significant percentage of whom were not familiar with the region's geography
9. The morphology of the coastline made beach access difficult in most cases (coastal coastlines), while accessible beaches were limited, which, combined with minimal visibility and a muddy atmosphere, contributed significantly to the beach. Invading a large number of citizens [19659002] 10. It is considered possible to change the behavior of the fire due to a change in the type of vegetation. The fire started in areas that had been burned in the past with low vegetation and high speed and headed to a place that had not been burned at any one time. recent fire with a particularly high concentration of fuel. This led to the fire supply and the release of higher energy from Neo Vuja to the coast. The east light of Marathon Avenue was turned into a fire that gathered all the surface vegetation and tall trees (active fire) as a "wall of fire" and in addition to several dozens of shores to the coast
11. In buildings with reinforced concrete load-bearing structure and masonry windows with closed windows, the fire did not pbad through the buildings, with the only effect of an external epidermal deformation of the coatings, without affecting the stability of the buildings due to the short duration of the fire.
12. On the contrary, in similar buildings with wooden or plastic windows and open, the fire pbaded inside and its effect was greater, high temperatures were developing, especially because of the burning of the fire. equipment inside buildings. non – structural elements of structures and their supporting structure
13. These cracks are unfortunately aggravated when extinguishing the fire that occurred in a construction as follows: The cement due to fire has developed heat. The water falls quickly, and the carrier's body drops sharply to about 50-55 degrees. Temperature drops create new cracks or widen existing cracks.
14. Well-constructed reinforced concrete buildings that have been in contact with the fire either by combustion or by exposure to heat radiation or by direct contact with the flames, but have not entered the buildings, have behaved very well with microbubbles on their non-structural exterior elements, mainly cracks in masonry filler and detachment of coatings due to high temperatures developed outside the building
15. The stability of the buildings affected by the fire depends on the burning time outside the building, whether the concrete has been calcined and at what depth or that the steel is in good condition due to the extended burning time inside the house
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