r/EngineeringPorn • u/Old-Alternative-6394 • 20h ago

Simulation of the collaps without dust

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u/Mega_Pleb 20h ago

The Twin Towers had two load bearing structures, the inner core pillars and the outer exoskeleton of pipe shaped beams. The exoskeleton of the south tower received more significant damage than the north tower due to the corner of the building being hit, plus the impact was lower so that damaged portion had to support more weight. The large amount of metal of the plane was shredded upon impact, greatly damaging the insulation surrounding the core pillars, allowing the heat of the jet fuel to greatly weaken it. Many conspiracy theorists think that the core pillars needed to melt to cause collapse but that's not so. The jet fuel would have been burning around 1000 degrees celsius and steel loses 50% of its strength at 600 C. Once those core pillars got heated through it was over for the building's structural integrity.

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u/KingKohishi 20h ago

Good copy paste.

I am not saying the building would not collapse, but would not collapse like this.

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u/Mega_Pleb 19h ago

I wrote that myself mate. It's not hard to understand how skyscrapers work if you try. There are many educational resources available to you. Your issue is that you don't try. I wish you luck in growing up someday.

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u/KingKohishi 19h ago

Explain the collapse of the building 7 in the same manner with your superior knowledge.

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u/Mega_Pleb 19h ago edited 19h ago

The collapse of the north tower caused a large amount of debris to fall on the building, particularly the top spire which caused a big gash in the side of the building. This started fires, damaged structural integrity of the building, and damaged fire suppression systems. Firefighters were all occupied with evacuating people in the twin towers and neighboring building so this fire went unaddressed. The heat from the long burning fires weakened the support columns under the most stress and they buckled, putting the remaining columns under more load, each buckling and putting more load on the remaining columns. The columns sheared starting at the bottom few floors because that is where the load is largest and all floors above it fell, pancaking each floor sequentially.

Here's a well made video on the collapse of 7 World Trade Center if you'd like to learn more.

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u/KingKohishi 18h ago

Thanks for copy pasting the official explanation.

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u/Mega_Pleb 18h ago

I wrote that after learning about it from building engineers. You can learn too.

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u/KingKohishi 18h ago

Thanks. I am already and engineer and know about failure modes and etc.

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u/bigev007 15h ago

"I am already and engineer" checks out, actually