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> any civil engineer could do the calculations in their sleep

The calculations can only be performed in Finite Element Analysis (FEA) software, doing this type of analysis (accurately) is impossible without computers.

>Its cost is probably wildly underestimated

There are also significant economic benefits to the hyperloop, in that it may be less expensive to maintain and power, while requiring much less rolling (floating?) stock. Rails are very expensive to maintain, largely because of the heavy loads they carry, and because they are entirely exposed to the elements.




I can't speak for civil engineers, but in mechanical engineering no one uses FEA to solve a cantilever beam. That's like using a supercomputer to calculate 3 times 4. Cantilever beam has bean studied for centuries and there are easy-to-use (and easy-to-prove) formulas for calculating its stress and strain.


From the post I was replying to:

>Hum. I got a different impression with regards to the FEM graphs of the beams' stresses. Dr. Drang seemed more bothered by the fact that they were there because it was too amateur, and too much pretty graphs for their own sake, since any civil engineer could do the calculations in their sleep.

smnrchrds, you are correct that simple structures have been studied, and equations describe their characteristics very accurately; what you are missing is that the FEMs in question were used to analyse a complex structure's response to vibration. I would challenge you to find any large bridge designed in the western world last 10 years without FEA.


> any civil engineer could do the calculations in their sleep

This sentence of Dr. Drang's article refers to FEA analysis of "applying a 1 g lateral acceleration to the three-pillar model and plotting out various stresses in the pillars". It's located directly below those plots and after his criticism of vibration analysis has finished. I agree that vibration analysis would be very hard without FEA, but applying a constant 1g lateral force to a cantilever beam could be easily done by paper and pen (well, maybe also a calculator) and is an overkill for FEA.




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