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Our achievements were feasible because of scale or the adaptation and evolution of technology. Space shuttles and airplanes were remarkable because they didn't require physical guideways for entire length of their journey. Now we have to build a guideway that is perfect and a vehicle that is faster than anything out there. How does one accomplish both of those with decades future resources? |
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Exactly. Even short tunnels like subways and sewers often run into lots of unforeseen conditions, because we really have a terrible sense of what's going on underground; water movements, changes in soil type, fault lines, gas deposits, and so forth all contribute to uncertainty in tunnel construction.
My sense is that in rural areas, one could use cut and cover techniques to keep the costs predictable, with very shallow tunnels and prefabricated tunnel sections. Even for this, the costs are predictable but not low - digging hundreds of miles of trench and then backfilling is not cheap. It is commonly done for oil pipelines, though not at the diameter needed for transport. In urban areas, you would need to use bored tunnels to avoid huge disruption to the surface, and since our urban areas are so sprawling, that's a lot of deep tunneling with lots of uncertainty. |
I have a mad respect for Mr Musk's dreams, he appears to be some kind of crazy billionaire freak that I find useful. But Hayward and ardecila are convincing (just as those 2 often are) in their exposure of actual constraints. We won't see such magic in our lifetimes. Those luckier who'll live long after us, possibly.
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Might not be the most pretty thing to look at, but, a 6 inch thick reinforced concrete circular section 8 to 10 meters in diameter at ground surface might be as cheap per kilometer as a two line freeway 8" or 10" slab for the same distance. |
I'm a big believer in Elon Musk. I've invested heavily in Tesla and will do so with SpaceX whenever it finally goes public. I think the guy has vision and the drive to accomplish it.
That being said, he's made some pretty ignorant comments lately poo-pooing California's High Speed rail project. Talk is cheap, and its easy to say that something that's currently just an untested concept in his mind is going to be so much better and cheaper than what is already planned for California. The thing is, infrastructure projects are expensive in America period, and his hyperloop - if ever built, won't be immune from that. There's eminent domain costs, tons of safety regulations, strict engineering tolerances, union labor, lawsuits, etc. His project would have to jump through all the same hoops that CAHSR is currently jumping through- all of which makes the costs balloon. It pisses me off because the CAHSR project is already on thin ice and has lost popularity in voters eyes. If there was another referendum on the ballot it could get yanked completely, and it would be decades before the project got started again. Musk has no business making comments to help derail a real-world project that is actually happening for an untested, conceptual, more-expensive-than-he-thinks-it-will-be project that only exists in his brain. |
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17 miles underground for $9 billion, with tolerances of what, nanometers? Ok probably not, but still. It does require a guideway system, essentially a tunnel-within-a-tunnel. The LHC cost $529 million/mile, so a 4,000 km system built to the same tolerances would cost ~$2.1 trillion. Surprisingly affordable for a nation such as the United States or the EU, as it is a fraction of GDP. |
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I want to be clear I believe Elon Musk should do whatever is possible to make this thing a close reality, but I hardly think this is achievable within our lifetimes excluding economic or political conditions. We simply don't have the right materials, automation and skill to put something like this together in the near future. To top it off, transportation developments are not static in innovation. People will continue to make faster, cleaner, smarter cars and planes. Some new creations will be used, others won't. |
Elon Musk Posts Plan to Annouce Hyperloop Transit System
http://www.bloomberg.com/news/2013-0...it-system.html Quote:
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my entire speach should be imagined to be narrated by the voice of this guy please. :gkwillie: |
As we've said before, massive infrastructure systems aren't like smartphones. They have community impacts and in America, that makes them intensely political.
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ELON MUSK: 'I'm Too Strung Out' To Build The Hyperloop Myself
http://www.businessinsider.com/musk-...himself-2013-8 Quote:
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I'm not an engineer but I'm having trouble conceptualizing how this thing wouldn't just blow up.
High speed trains that at most travel about 200 mph, or 300+ during tests, run over semi-flexible steel rails anchored to the ground or maglev guideways with an air cushion between the vehicle and the beam. In the event that hot weather causes a rail to slightly warp isn't necessarily catastrophic and in the worst case scenario the train will just ditch to the ground and scrape itself to a stop. But a sled going "Ludicrous Speed" inside a small pipe, what if the pipe is slightly warped? Won't it catastrophically fail and smash up? |
^ That's what I pointed out earlier. Mankind lacks competency in construction precision at that scale. Any sort of deviance in the tunnel profile would create extreme turbulence that would destroy the vehicle. Even if you could build the tunnel, you are at the mercy of Earth's forces causing subsidence and creep in the construction. I suppose one solution is building a vehicle entirely monolithic. Maybe 3D printed out of some super strength material where bonds could resist some pretty extreme forces.
Ideally this thing needs to be designed to be fast but within reasonable tolerances of construction. Plus it must be engineered to withstand schedules of deferred maintenance. America's bridges in comparison would be much cheaper and easier to maintain and how are we doing with that track record? Musk is successful and convincing in his ideas because he achieves just above the curve of innovation. But this idea is way off in the future. By then our priorities may change as well as our attitudes on mobility. Is the shorter time it takes to get across the country make us better as a society or can we do more with faster planes? |
^ Potentially, but the current fossil-fuel based approach to aviation is insanely unsustainable. IIRC high-speed rail is no less wasteful of energy but the electricity for electrified trains can come from any source imaginable while planes can only run on fossil fuels.
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Don't forget that the capital costs and energy to dig 1000+ km tunnels will also be "ludicrous." I like to think that anything is possible in the future, but what is the advantage of some sort of scheme like this? I'm also trying to imagine the engineering nightmare to digging a downtown station in an existing city - through the maze of existing geological features, transportation, infrastructure and utilities. San Francisco will be lucky to build its tiny train station for the CAHSR station in downtown, let alone a dead-straight zero-tolerance tube from SF to LA. Or NYC to DC. At lease the Japanese started on their maglev train, which will cost $65 billion+, while here in America we pipe dream while sitting on craptastic, outdated infrastructure. Maybe it makes us feel better to tell ourselves we are superior because we can envision superior transpo systems and tech, while the rest of the world actually HAS better systems! :tup: |
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