Chapter 21 High-Rise Building Collapse

Question 1

What was the most important lesson learned from 9/11?

Answer 1

building seven collapsed solely because of fire destruction

Question 2

the collapse of building seven must be considered a benchmark in the fire service, what did it teach the fire service

Answer 2

1. structural stability of a burning modern lightweight high-rise skeleton still building must be questioned
2. high-rise can collapse after a seven hour free burn time
3. 10 floors of fire brought down the building
4. 47 story skeleton building collapse and 13 seconds
5. passive fire protection provided by construction did not stop the spread of fire

Question 3

what should command prepare for in the event of an uncontrolled high-rise fire

Answer 3

rare event of global collapse of a high-rise burning building

Question 4

what started the global collapse of World Trade Center building seven

Answer 4

thermal expansion from the heat of the fire on the 13th floor caused the fluted steel floor deck to expand more than the concrete above. the connections of the composite concrete and steel decking failed, floor beams expanded and pushed out a girder, the girder pulled away from a column the unconnected column buckled and global collapse began

Question 5

why did the sprinklers on the lower floors of the World Trade Center seven out of function

Answer 5

the sprinklers on the lower floor of World Trade Center seven were supplied by water mains that were damaged by the collapse of towers one and two

Question 6

on what sides of the building was vertical auto exposure observed

Answer 6

West and North side

Question 7

NIST states fired a structural one cause the collapse of building seven. this cascading progressive building collapse after___ hours of uncontrolled burning

Answer 7

7, but in reality 5 hours and ten min

Question 8

what was the exact cause of failure in World Trade Center building seven

Answer 8

thermal expansion

Question 9

progressive collapse is also known as

Answer 9

disproportionate collapse, spread of local damage from the initiating event, from element to element, eventually resulting in the collapse of the entire structure or disproportionately large part of it

Question 10

what was an important impact factor for fires spread of combustible content in building seven

Answer 10

open floor design, there were also dwarfed partitions.. these walls extended only to the underside of the ceiling

Question 11

how many has put out the Meridian Plaza building fire, which was the first high-rise fire firefighters were withdrawn from

Answer 11

9 sprinkler heads

Question 12

how long are fire-resistive steel frames protected against heat?

Answer 12

4 hours

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