It's a mystery. The towers buckled and collapsed on itself. I don't know how another structure could collapse from "debris" there is a whole entire conspiracy of it being insurance fraud which is possible one of the owners of the twin towers filed insurance on it a couple weeks before it happened. I watched a video a while back where a past CIA agent explains that the government knew that it was going to happen they just weren't sure when

It fell because the primary column buckled. The top floor penthouse collapsed and fires burned around it, once the roof and top floor fell the weight pushed the rest down, gathering weight and power as it fell, floor by floor.

Woodkid wrote It fell because the primary column buckled. The top floor penthouse collapsed and fires burned around it, once the roof and top floor fell the weight pushed the rest down, gathering weight and power as it fell, floor by floor.

is this a poor design flaw?

aMio wrote

Woodkid wrote It fell because the primary column buckled. The top floor penthouse collapsed and fires burned around it, once the roof and top floor fell the weight pushed the rest down, gathering weight and power as it fell, floor by floor.

is this a poor design flaw?

Not really. I don't think they expected the two towers next to it to be hit by planes, and that's really the only reason the top floor and primary column would have collapsed at the top.

But I'm not a structural engineer or architect so my opinion means absolutely nothing.

Woodkid wrote

aMio wrote

Woodkid wrote It fell because the primary column buckled. The top floor penthouse collapsed and fires burned around it, once the roof and top floor fell the weight pushed the rest down, gathering weight and power as it fell, floor by floor.

is this a poor design flaw?

Not really. I don't think they expected the two towers next to it to be hit by planes, and that's really the only reason the top floor and primary column would have collapsed at the top.

But I'm not a structural engineer or architect so my opinion means absolutely nothing.

It doesn't make sense, because the towers buckled on themselves or did a steel beam sneaks its way on top of that building?

aMio wrote

Woodkid wrote

aMio wrote

Woodkid wrote It fell because the primary column buckled. The top floor penthouse collapsed and fires burned around it, once the roof and top floor fell the weight pushed the rest down, gathering weight and power as it fell, floor by floor.

is this a poor design flaw?

Not really. I don't think they expected the two towers next to it to be hit by planes, and that's really the only reason the top floor and primary column would have collapsed at the top.

But I'm not a structural engineer or architect so my opinion means absolutely nothing.

It doesn't make sense, because the towers buckled on themselves or did a steel beam sneaks its way on top of that building?

No, the primary column runs straight through the centre of the building from the foundations all the way up to the roof. The penthouse roof collapsed and fires burned inside and around that primary column. Steel doesn't need to melt completely to become weak and able to buckle, especially with the weight being pressed down on-top of it with the roof and floor around it now not being strong enough to hold itself up [because other, non-primary, columns had collapsed.]

Woodkid wrote

aMio wrote

Woodkid wrote

aMio wrote

Woodkid wrote It fell because the primary column buckled. The top floor penthouse collapsed and fires burned around it, once the roof and top floor fell the weight pushed the rest down, gathering weight and power as it fell, floor by floor.

is this a poor design flaw?

Not really. I don't think they expected the two towers next to it to be hit by planes, and that's really the only reason the top floor and primary column would have collapsed at the top.

But I'm not a structural engineer or architect so my opinion means absolutely nothing.

It doesn't make sense, because the towers buckled on themselves or did a steel beam sneaks its way on top of that building?

No, the primary column runs straight through the centre of the building from the foundations all the way up to the roof. The penthouse roof collapsed and fires burned inside and around that primary column. Steel doesn't need to melt completely to become weak and able to buckle, especially with the weight being pressed down on-top of it with the roof and floor around it now not being strong enough to hold itself up [because other, non-primary, columns had collapsed.]

We're still talking about this building that collapsed near the twin towers right?

aMio wrote

Woodkid wrote

aMio wrote

Woodkid wrote

aMio wrote

Woodkid wrote It fell because the primary column buckled. The top floor penthouse collapsed and fires burned around it, once the roof and top floor fell the weight pushed the rest down, gathering weight and power as it fell, floor by floor.

is this a poor design flaw?

Not really. I don't think they expected the two towers next to it to be hit by planes, and that's really the only reason the top floor and primary column would have collapsed at the top.

But I'm not a structural engineer or architect so my opinion means absolutely nothing.

It doesn't make sense, because the towers buckled on themselves or did a steel beam sneaks its way on top of that building?

No, the primary column runs straight through the centre of the building from the foundations all the way up to the roof. The penthouse roof collapsed and fires burned inside and around that primary column. Steel doesn't need to melt completely to become weak and able to buckle, especially with the weight being pressed down on-top of it with the roof and floor around it now not being strong enough to hold itself up [because other, non-primary, columns had collapsed.]

We're still talking about this building that collapsed near the twin towers right?

Yes, why? Perhaps I'm not very good at explaining it.

Debris from the collapse of WTC 1, which was 370 feet to the south, ignited fires on at least 10 floors in the building at its south and west faces. However, only the fires on some of the lower floors-7 through 9 and 11 through 13-burned out of control. These lower-floor fires-which spread and grew because the water supply to the automatic sprinkler system for these floors had failed-were similar to building fires experienced in other tall buildings. The primary and backup water supply to the sprinkler systems for the lower floors relied on the city's water supply, whose lines were damaged by the collapse of WTC 1 and WTC 2. These uncontrolled lower-floor fires eventually spread to the northeast part of WTC 7, where the building's collapse began.

How did the fires cause WTC 7 to collapse?

The heat from the uncontrolled fires caused steel floor beams and girders to thermally expand, leading to a chain of events that caused a key structural column to fail. The failure of this structural column then initiated a fire-induced progressive collapse of the entire building.

According to the report's probable collapse sequence, heat from the uncontrolled fires caused thermal expansion of the steel beams on the lower floors of the east side of WTC 7, damaging the floor framing on multiple floors.

Eventually, a girder on Floor 13 lost its connection to a critical column, Column 79, that provided support for the long floor spans on the east side of the building (see Diagram 1). The displaced girder and other local fire-induced damage caused Floor 13 to collapse, beginning a cascade of floor failures down to the 5th floor. Many of these floors had already been at least partially weakened by the fires in the vicinity of Column 79. This collapse of floors left Column 79 insufficiently supported in the east-west direction over nine stories.

The unsupported Column 79 then buckled and triggered an upward progression of floor system failures that reached the building's east penthouse. What followed in rapid succession was a series of structural failures. Failure first occurred all the way to the roof line-involving all three interior columns on the easternmost side of the building (79, 80, 81). Then, progressing from east to west across WTC 7, all of the columns failed in the core of the building (58 through 78). Finally, the entire faade collapsed.

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Woodkid wrote

aMio wrote

Woodkid wrote

aMio wrote

Woodkid wrote

aMio wrote

Woodkid wrote It fell because the primary column buckled. The top floor penthouse collapsed and fires burned around it, once the roof and top floor fell the weight pushed the rest down, gathering weight and power as it fell, floor by floor.

is this a poor design flaw?

Not really. I don't think they expected the two towers next to it to be hit by planes, and that's really the only reason the top floor and primary column would have collapsed at the top.

But I'm not a structural engineer or architect so my opinion means absolutely nothing.

It doesn't make sense, because the towers buckled on themselves or did a steel beam sneaks its way on top of that building?

No, the primary column runs straight through the centre of the building from the foundations all the way up to the roof. The penthouse roof collapsed and fires burned inside and around that primary column. Steel doesn't need to melt completely to become weak and able to buckle, especially with the weight being pressed down on-top of it with the roof and floor around it now not being strong enough to hold itself up [because other, non-primary, columns had collapsed.]

We're still talking about this building that collapsed near the twin towers right?

Yes, why?

Debris from the collapse of WTC 1, which was 370 feet to the south, ignited fires on at least 10 floors in the building at its south and west faces. However, only the fires on some of the lower floors-7 through 9 and 11 through 13-burned out of control. These lower-floor fires-which spread and grew because the water supply to the automatic sprinkler system for these floors had failed-were similar to building fires experienced in other tall buildings. The primary and backup water supply to the sprinkler systems for the lower floors relied on the city's water supply, whose lines were damaged by the collapse of WTC 1 and WTC 2. These uncontrolled lower-floor fires eventually spread to the northeast part of WTC 7, where the building's collapse began.

How did the fires cause WTC 7 to collapse?

The heat from the uncontrolled fires caused steel floor beams and girders to thermally expand, leading to a chain of events that caused a key structural column to fail. The failure of this structural column then initiated a fire-induced progressive collapse of the entire building.

According to the report's probable collapse sequence, heat from the uncontrolled fires caused thermal expansion of the steel beams on the lower floors of the east side of WTC 7, damaging the floor framing on multiple floors.

Eventually, a girder on Floor 13 lost its connection to a critical column, Column 79, that provided support for the long floor spans on the east side of the building (see Diagram 1). The displaced girder and other local fire-induced damage caused Floor 13 to collapse, beginning a cascade of floor failures down to the 5th floor. Many of these floors had already been at least partially weakened by the fires in the vicinity of Column 79. This collapse of floors left Column 79 insufficiently supported in the east-west direction over nine stories.

The unsupported Column 79 then buckled and triggered an upward progression of floor system failures that reached the building's east penthouse. What followed in rapid succession was a series of structural failures. Failure first occurred all the way to the roof line-involving all three interior columns on the easternmost side of the building (79, 80, 81). Then, progressing from east to west across WTC 7, all of the columns failed in the core of the building (58 through 78). Finally, the entire faade collapsed.

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what caused the penthouse roof to collapse and a fire to break out. Even if a column broke what would have caused that?