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SpaceX Hyperloop Pod Competition

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Re: SpaceX Hyperloop Pod Competition

#81

Post by thechao »

mixmastamyk wrote: post #49

If it works well, I'd like to see these in LA or other big cities too, not just long distance. Would be great to get on one of these and end up at the beach in Santa Monica at high speed instead of suffering through traffic.

Texas triangle:

    San Antonio  Austin  Dallas
    Houston  Dallas
    House  San Antonio
That'd link up 14—17 million people. Expected growth is another 10 million over the next 20 years.

At an average speed of 600mph, it'd be about 25m commute between points, worst case.

Re: SpaceX Hyperloop Pod Competition

#82

Post by DuskStar »

martinald wrote: post #75

The projections of capacity seem way too low. It says it can do 840passengers/hour. In the UK each 11 car train on the West Coast Mainline can take about 600 passengers seated + maybe slightly over 100 more standing. So around 700. We have 3 trains per hour between London and Birmingham, which adds up to a rough capacity of 2200 per hour. This doesn't even take into account the multitude of slower trains that go betw…

To be fair, Birmingham London is 125 miles, while Los Angeles San Francisco is 380 miles. A better comparison would be Edinburgh London, at 410 miles or so. At those distances, required capacity probably drops off.

Re: SpaceX Hyperloop Pod Competition

#83

Post by elektromekatron »

lisper wrote: post #50
mixmastamyk wrote: post #45

Earlier quoted context omitted.

Why not over the parking lots or back alleys, etc?

Cost. A full-scale hyperloop needs to be on pylons, but a 1-mile test track can be built directly on the ground, which would be a lot cheaper. Why pay for pylons if you don't have to?

So you can test the pylons.

Re: SpaceX Hyperloop Pod Competition

#84

Post by [deleted] »

abduhl wrote: post #51
gknoy wrote: post #37

Earlier quoted context omitted.

I am pretty sure you were joking, but just in case ... Elon already sat down and decided to learn enough rocket science to found SpaceX, and enough engineering to found Tesla. He's learned more in his "spare time" than most of us have learned at university, and then has gone on to apply the lever of business to it. If Elon felt that it were necessary to get his pet project done, I believe he'd make time to master civ…

Civil engineering is fairly rigid and defined by applicable building codes. There isn't any real room to innovate in the industry, at least in the public sector. "Mastering" civil engineering just entails becoming familiar with the code and then it becomes a game of politics and liability. More likely, he would just hire a civil engineering firm. Laws throughout the country are such that you can't really buy your way…

[deleted]

Re: SpaceX Hyperloop Pod Competition

#85

Post by frankus »

martinald wrote: post #75

The projections of capacity seem way too low. It says it can do 840passengers/hour. In the UK each 11 car train on the West Coast Mainline can take about 600 passengers seated + maybe slightly over 100 more standing. So around 700. We have 3 trains per hour between London and Birmingham, which adds up to a rough capacity of 2200 per hour. This doesn't even take into account the multitude of slower trains that go betw…

I had the same thought. The waitbutwhy article cites 840 per hour being slightly less than the current traffic for that city pair, but that's assuming quite non-peaky traffic (7+ million if run 24/7).

It's also assuming that the demand at a cost of $20 and 35 minutes will be roughly the same as it is now.

Re: SpaceX Hyperloop Pod Competition

#86

Post by elektromekatron »

abduhl wrote: post #66
btilly wrote: post #54

Earlier quoted context omitted.

The answer is an emphatic no. Concrete can do many things, but it will not hold back a slip fault. Concrete roads, bridges, etc will buckle and break in the slip zone no matter what they are rated for. Take the 1906 earthquake as an example. As http://pubs.usgs.gov/gip/earthq3/move.html says, the horizontal slip was 21 feet at one point. Something like the Hyperloop has to be designed with the expectation of facing a…

How is the issue of a horizontal slip different for a tunnel versus for an above ground structure? Neither piece of infrastructure can be economically designed to withstand a seismic movement if the structure crosses the fault where the offset occurs. Why does the possibility of an offset result in a tunnel being an "emphatic no" while still allowing for this pylon idea?

You can include base isolation for pylons crossing known faults. - https://en.wikipedia.org/wiki/Base_isolation

Re: SpaceX Hyperloop Pod Competition

#88

Post by Animats »

The original Hyperloop system was supposed to be powered by linear induction motors spaced along the track. The pod doesn't have propulsion capability, except maybe an emergency system. So the pod/track interface is pretty much set by the propulsion system.

For trains, linear induction motors have usually been paired with magnetic levitation, as in the Transrapid system. But they don't have to be. Many roller coasters with a linear induction motor launch system have been built; Flight of Fear at King's Dominion, by Premiere Rides, was the first, in 1996. For a 1-mile test track, outsourcing the whole job to Premiere Rides or Intamin would be a good move. Intamin, which mostly makes amusement park rides, also has a transportation division. They build monorail systems. Intamin would just have to combine the car design from their P8 monorail[1] with their linear induction motor launch system.[2] By Intamin standards, a fast 1 mile loop with no hills is easy. ("We can put in a vertical loop for a small extra charge...")

[1] http://www.intaminworldwide.com/transportation/Home/news/Sha... [2] http://www.intaminworldwide.com/amusement/RollerCoasters/LSM...

Re: SpaceX Hyperloop Pod Competition

#89

Post by [deleted] »

abduhl wrote: post #51
gknoy wrote: post #37

Earlier quoted context omitted.

I am pretty sure you were joking, but just in case ... Elon already sat down and decided to learn enough rocket science to found SpaceX, and enough engineering to found Tesla. He's learned more in his "spare time" than most of us have learned at university, and then has gone on to apply the lever of business to it. If Elon felt that it were necessary to get his pet project done, I believe he'd make time to master civ…

Civil engineering is fairly rigid and defined by applicable building codes. There isn't any real room to innovate in the industry, at least in the public sector. "Mastering" civil engineering just entails becoming familiar with the code and then it becomes a game of politics and liability. More likely, he would just hire a civil engineering firm. Laws throughout the country are such that you can't really buy your way…

[deleted]

Re: SpaceX Hyperloop Pod Competition

#90

Post by abduhl »

btilly wrote: post #70
abduhl wrote: post #66

Earlier quoted context omitted.

How is the issue of a horizontal slip different for a tunnel versus for an above ground structure? Neither piece of infrastructure can be economically designed to withstand a seismic movement if the structure crosses the fault where the offset occurs. Why does the possibility of an offset result in a tunnel being an "emphatic no" while still allowing for this pylon idea?

The pylons are built with an internal structure allowing them to move horizontally both ways, and vertically. The tube itself can remain stationary in the air. We do not have a cost effective way to allow the tube to remain stationary if it is attached to the ground and the ground moves. And avoiding buckling and sudden bends kind of matters when you're traveling at mach 1. Search for "earthquake" in http://www.space…

I'm sorry but no - this does not answer the question. Expansion joints and "lateral dampers" do not make the problem of a joint offset go away. In order to resist a horizontal or vertical offset of 20+ feet with the tube "remaining stationary" then the pylon must be built to allow an extra 40+ feet to account for this movement.

How, exactly, does the pylon not suffer the same design flaw as the tunnel under the use case that you yourself brought up of a horizontal or vertical offset occuring along a splay?

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