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Totally rando thought - what is level?
- Thread starter ThinkFast
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alien
Length. Longer projects like bridges, tunnels, highways… have to factor the earths curvature and will have a scale factor applied to horizontal measurements. Smaller stuff like buildings no matter how tall can assume the earth is flat and plane geometry is applied.What are the criteria for “larger?” Mass? Area? Footprint? Height?
I love me some good mega project factoids
ThinkFast
Live Long
Scale factor. Interesting. So is that used to correct for the delta between the straight line distance and the chord of the arc distance when going to the same points?
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alien
It’s a factor applied to convert 2D geometry to spherical geometry such as going from a design created on a flat plane of paper or CAD screen to being constructed on the curved earths surface, which is actually represented mathematically as an ellipsis.
You can’t drape a flat 2D surface over the earth without distorting it. The scale factor accounts for that distortion.
It also accounts for the distortion caused by elevation. Same 2D design dimensions of something designed as if at sea level will have to be stretched if constructed at a higher elevation such as Denver because the spherical radius is greater being further from the center of the earth. So one best fit scale factor is applied to account for all corrections needed.
All covered under geodetics and geodesy.
You can’t drape a flat 2D surface over the earth without distorting it. The scale factor accounts for that distortion.
It also accounts for the distortion caused by elevation. Same 2D design dimensions of something designed as if at sea level will have to be stretched if constructed at a higher elevation such as Denver because the spherical radius is greater being further from the center of the earth. So one best fit scale factor is applied to account for all corrections needed.
All covered under geodetics and geodesy.
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ThinkFast
Live Long
My industrial engineering curriculum required cross-discipline electives in thermodynamics, materials science, and electrical engineering. But nothing from civil engineering, which is where I’m guessing this would’ve been covered.
It makes perfect sense - just a concept I was never exposed to during my schooling, and never really came up since then. Love it. Thank you for explaining.
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Clicked on thread expecting a philosophical discussion, instead, found a bunch of nerds flexing their critical thinking muscles.
Still interesting but now my brain hurts and I need to take a nap
I have a question though before I take a nap.... How did you mount the blinds?
Still interesting but now my brain hurts and I need to take a nap
I have a question though before I take a nap.... How did you mount the blinds?
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nakedape
Well-known member
In construction codes a .5" difference is allowable over a certain distance I can't remember but it's less than a large room. Found out the hard way installing a long shelf for a friend in her office. Holy gap batman.
Doggy style?
"Bring me the butter."
bobl
Well-known member
When installing slabs for park tables, we used to say "everybody looks, nobody measures". This because you are often installing something next to something that is not itself square. So you make it as visually square as possible, and the hell with an exact measurement. Same with picture hanging.