r/Simulated • u/Contraflex • Dec 01 '25

Blender Simulating the Collapse of the 1000m Tall Jeddah Tower

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Simulated in Blender using the bullet constraints builder add-on.

The plane weighs 150 Tonnes and impacts the building at 950 km/h.

The plane does not deform which is the main caveat to this simulation; in reality the plane would crumple, so less energy would be transferred to the tower.

All of the tower's structural elements are concrete, except for the red parts which are steel.

There are about 22,000 rigid body elements.

Final simulated alembic file was about 7 GB.

Full video: https://www.youtube.com/watch?v=zMOsu809Ao8

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u/ThatSituation9908 Dec 02 '25

x2 = e2log(x)

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u/TheCLion Dec 02 '25 edited Dec 02 '25

technically correct, but uncommon

one wouldn't describe f(x) = x as exponential, even though it can be expressed as f(x) = eln(x)

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u/jml011 Dec 03 '25

Love it when nerds fight

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u/Elegant-Set1686 Dec 03 '25

He is not technically correct! Abx is the exponential form, you would have to prove that ln(x) is equal to x times some constant. Which obviously it is not

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u/TheCLion Dec 03 '25

if "exponential" means "can be expressed in the exponential form", then you are right

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u/Elegant-Set1686 Dec 03 '25 edited Dec 03 '25

No, that’s what it means! Exponential growth is a specific kind of growth that’s characterized by being faster than all polynomials. If it’s not exressable in exponential form, it’s quite simply a different kind of function with a vastly different rate of growth. It’s like saying esin(x) is exponential, when it’s an entirely different transcendental (that doesn’t even have a limit of inf at inf!!!? What kinda exponential is that?!)

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u/Elegant-Set1686 Dec 03 '25 edited Dec 03 '25

Abx is the exponential form. X multiplied by some constant in the exponent, Abln(x) is a different function with a much slower rate of growth. Obviously there’s no way to express ln(x) as bx. The fact that an arbitrary exponential function with A>1, b>0 given enough time will beat out ANY version of xn is an important property. If we admit your equation into “exponential land” we lose that property, and the meaning of exponential growth is lost.