Citat:
Det enda du har tagit upp här är att det "buktade ut" lite i ett av byggnadens hörn. Artikel från 1997 på firehouse.com underavdelning Operations & Training:
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Building Collapse Indicatorshttps://www.firehouse.com/operations...pse-indicators
The exterior walls of a building, more than any other component, can contain a multitude of collapse indicators. There are many indicators that can be seen and many that will not be visible. As the exterior wall is being attacked, it can react in a variety of ways.
Typical wall collapse indicators:
Smoke showing through walls
Fire showing through a wall
Old wall cracks enlarging
New wall cracks
Bulging walls
Leaning walls
Failure of part of a wall
Visible spalling of a brick wall
Spalling of concrete and exposing of steel
A wall breaking down under a hose stream
Wall spreaders
....
. Steel beams attacked by the heat of the fire causes them to expand. Steel expands approximately 9 1/2 inches per 100 feet. A fireground rule of thumb for steel expansion is one inch for every 10 feet of steel. As steel is subjected to high temperatures, it will absorb the heat until its failure temperature is reached, commonly set between 1,100 and 1,500 degrees Fahrenheit. It will then fail, often pulling or pushing down other structural members with it.
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Jag fetade några av de mest uppenbara punkterna som brandchefen vid wtc7 kan ha tagit hänsyn till...
Building collapse dangershttps://www.firerescue1.com/fire-car...XUHzU4lc5m04F/
While the following list is in no way complete, it serves as a prompt when evaluating the stability of a burning structure you are working in or around.
1. Building construction type
2. Occupancy type
3. Age of building
4. Known structural remodeling
5. Walls out of plumb/bulging/bowing
6. Deteriorated mortar joints and masonry
7. Cracks in exterior or interior walls
8. Water/Smoke coming out of cracks in masonry
9. Sagging floors
10. Truss construction
11. Fire impinging on the dead load support structure of the building
12. Significant volume of fire
13. Significant fuel load
14. Impact of suppression activities on structure
15. Length of interior operations
16. Sound made by a moving building: groans, cracks, etc.
17. Multiple fires in the same building or damage from previous fires.
All of these factors will assist the initial fire officer when making the offensive versus defensive attack decision.
1. Källa på att skyskrapor av stål totalkollapsar i fritt fall om det "buktar ut" lite i ett av hörnen.
2. Källa på att närvarande expertis var "tränad" i att göra den bedömningen avseende skyskrapor av stål.
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Senast redigerad av onopono 2020-11-18 kl. 23:02.
Senast redigerad av onopono 2020-11-18 kl. 23:02.