Federer/Nadal

[TimberWolf]

Because it's highly unlikely they'd fall evenly. In the nightmare-case scenario, they'd topple.

To resist falling straight down the remaining parts of a building would have to resist huge tensile forces, and for a building the size of the towers this would appear to be a tall proposition. Without huge strength in the structure it would want to come straight down, fast. Towers and buildings can be made to topple, but only by using specially placed charges in a sound building. It would be much more difficult to achieve a lot of topple in a building the size of the towers IMO.

[James Tiberius Kirk]

You've forgotten the Giant Alien Lizard contribution... we thought the War Criminal's Great Great Great Grandfather might have been there.

You'll never get me reptile...

[realityhack]

It would be much more difficult to achieve a lot of topple in a building the size of the towers IMO.

Actually, their height makes them more likely to topple. The law of conservation of energy makes it very hard for me to believe it was a natural collapse. Possible, but highly improbable. And for all three?
There are many architects and engineers who believe the same. Some have modelled this using a range of scenarios, and concluded only in favour of controlled demolition.

[BrilloPad]

I dont believe the towers collapsed atall. I think it was filmed on a film set in Vegas. Or was it the moon?

[TimberWolf]

Actually, their height makes them more likely to topple. The law of conservation of energy makes it very hard for me to believe it was a natural collapse. Possible, but highly improbable. And for all three?
There are many architects and engineers who believe the same. Some have modelled this using a range of scenarios, and concluded only in favour of controlled demolition.

LOL, The law of conservation of energy

When they built the towers they would have calculated how much it could lean to one side - which places an upper limit on the angle it could topple, gravity would take care of the rest. When the steelwork is weaked through heat, this angle would be much less. Tall buildings can't be made topple like trees, they just don't have the same strength.

[realityhack]

Or was it the moon?

Your position has been logged. Stay where you are, the authorities are on their way, do not attempt to raise alarm, or leave the building.

[BrilloPad]

Your position has been logged. Stay where you are, the authorities are on their way, do not attempt to raise alarm, or leave the building.

But I was in Finsbury Circus

[realityhack]

LOL, The law of conservation of energy

When they built the towers they would have calculated how much it could lean to one side - which places an upper limit on the angle it could topple, gravity would take care of the rest. When the steelwork is weaked through heat, this angle would be much less. Tall buildings can't be made topple like trees, they just don't have the same strength.

Yep, as a counter to the 'pancake theory' the FEMA report used to explain the collapse, saying the generated forces produced the neat fall.
I see where you're coming from, but I'm not saying they should have toppled like 'trees' at all. more that upper parts of the building would be more likely to fall away and to one side, especially if the forces were uneven.

I'll have to come back to this later - lunch.

[realityhack]

But I was in Finsbury Circus

Damn, busted. Stay where you are anyway, the police will eventually find you. Thank you for your co-operation.

[TimberWolf]

Yep, as a counter to the 'pancake theory' the FEMA report used to explain the collapse, saying the generated forces produced the neat fall.
I see where you're coming from, but I'm not saying they should have toppled like 'trees' at all. more that upper parts of the building would be more likely to fall away and to one side, especially if the forces were uneven.

I'll have to come back to this later - lunch.

The greatest tendency would be to come straight down (hence the term falling down, rather than falling sideways ), and more so with tall buildings. I am well aware of the conservation of energy, but this is a staw-man without explanation, since CoE only means what it says, and that is that the building would happily stay where it is.

To get an idea of the forces involved in toppling just have a guess. At an angle theta to the vertical, the sideways force on the framework would be on the order of m*g*sin(theta). At zero degrees this is zero in a horizontal direction, and the way things should be, downward compressive forces only. At 30 degrees the framework would have to withstand 50% of the weight of building - sideways . A tensile force in a direction it isn't designed to withstand, and only one bolt has to fail before irt collapses rather than topples. It couldn't topple much.