[JPKab]

You're focused too much on the vacuum aspect of the tube, and not nearly enough on the fact that it's a tube, with enough self-support to be elevated on pylons and is an order of magnitude easier to build than pouring a foundation for maglev tracks.

High speed rail track is dramatically more difficult and expensive to build than a hyperloop tube system. This was, from the beginning, the huge differentiator between the two. Hyperloop tubes aren't comparable to road or rail bridges/tracks, but instead are comparable to constructing oil/gas/water pipelines. We know how much easier it is already to build those.

[soyiuz]

See my comment above. An elevated (or submerged) tube with rails (or a track) inside cannot be less expensive than those rails or track elevated (or submerged) alone. I get the pipeline metaphor, but a pipeline with infrastructure inside is just infrastructure + pipeline. So instead of a train system the proposal has always been to build a train system inside a pipeline, which has to be more expensive than either. We have no indication of cost savings here.

[sroussey]

I agree, though in city, it would be cheaper to use air rights than on the ground or underground.

[Schiendelman]

It never works that way - agencies have tried with elevated systems for a century. You have to buy the land.

[bigbubba]

Hyperloop tubes are pipe dreams, nobody has actually ever build one, so all the pros you cite are purely speculative.

[rini17]

Roads and rails can have small gaps to allow for stretching from temperature changes. Pipelines solve this with U-shaped segments. Hyperloop can't do either, requires something with airtight-enough seals or some expensive materials.

At such high speeds as proposed, any sagging is impermissible (again, unlike pipelines). Of course it's solved engineering problem but it markedly increases the construction price and complexity.

So, no, hyperloop is not really comparable to pipelines.

[jcranmer]

> Hyperloop tubes aren't comparable to road or rail bridges/tracks, but instead are comparable to constructing oil/gas/water pipelines.

How many pipelines are wide enough diameter to move an entire vehicle and designed to handle the stress of multi-ton vehicles as their dynamic loads? And how many of those are supported on pylons rather than being fully buried?