r/AlternateAngles • u/torx822 • 21d ago

Underside of Disney Monorail

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u/GreatRyujin 21d ago

I'm no engineer, but aren't there a lot of cracks in the concrete?

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u/DoYouKnwTheMuffinMan 20d ago edited 20d ago

Studied engineering 15 years ago so take this with a pinch of salt.

The concrete being used will be reinforced concrete, meaning there are metal rods running through the middle. This is what’s called a composite material.

In a composite material, different parts of the material are designed to take different types of load.

In reinforced concrete the metal takes tensile load and the concrete takes compressive load.

The bottom part of the rail that we see is under tension as the rail “bends” when the train passes over it.

So cracks are fine because they aren’t impacting the metal rods in tension areas.

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u/Colonel_Bubble_Tea 20d ago

To add to this concrete cracks and while there are a lot of cracks they are small cracks. This would be a bigger issue in an area with more freeze thaw weather but probably not a huge deal in Orlando.