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SpaceX Hyperloop Pod Competition

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Re: SpaceX Hyperloop Pod Competition

#61

Post by toomuchtodo »

abduhl wrote: post #53
toomuchtodo wrote: post #34

Earlier quoted context omitted.

"The machine is a remarkable and unique piece of equipment. Purpose-built for Crossrail by German firm Herrenknecht – one of a handful of TBM manufacturers in the world – it cost around £10m ($15m), weighs close to 1,000 tonnes, has an external diameter of 7.1 metres (23ft) and from cutting-face-to-end stretches 150m (500ft)." http://www.bbc.com/future/story/20150602-crossrail-the-monst...

TBMs are typically built specifically for a job and its ground conditions. Depending on the type of ground, the machine can be a different type of machine that uses different tooling. This will ultimately drive TBM cost. It is possible to reuse machines but this is, again, dependent on geology. Anyways, the cost of a TBM is generally not the most expensive part of a tunneling operation.

> Anyways, the cost of a TBM is generally not the most expensive part of a tunneling operation.

What is the most expensive part?

Re: SpaceX Hyperloop Pod Competition

#62

Post by phpnode »

toomuchtodo wrote: post #61
abduhl wrote: post #53

Earlier quoted context omitted.

TBMs are typically built specifically for a job and its ground conditions. Depending on the type of ground, the machine can be a different type of machine that uses different tooling. This will ultimately drive TBM cost. It is possible to reuse machines but this is, again, dependent on geology. Anyways, the cost of a TBM is generally not the most expensive part of a tunneling operation.

> Anyways, the cost of a TBM is generally not the most expensive part of a tunneling operation. What is the most expensive part?

Labour costs. TBMs are amazing but they are slow and require a whole lot of infrastructure. It's not just a case of sticking them in the ground, turning them on and waiting for a nice tunnel to materialize. For instance, what do you with the excavated dirt? To give you an indication of the sheer cost here, London's crossrail project runs at approximately £4m/day - https://en.wikipedia.org/wiki/Crossrail

Re: SpaceX Hyperloop Pod Competition

#63

Post by michaelbarton »

This immediately reminded me of the early days of steam when, very similarly, at Rainhill a one mile test track of railway was constructed and people were invited to compete their different locomotives. The winner was Stevenson's rocket which amazed the large crowd by travelling at a heady top speed of 30mph.

An "also ran" was the amusing cycloped, the only non-steam entry, a horse on top of a treadmill walking the carriage forward.

Re: SpaceX Hyperloop Pod Competition

#64

Post by ajays »

toomuchtodo wrote: post #16
kiba wrote: post #12

Earlier quoted context omitted.

Elon Musk doesn't have the time to learn civil engineering, property development, let alone the politics surrounding it.

After Elon said "fuck it" and built his own rocket motors after getting screwed by the Russians, I don't see him wasting any time with politics or property development (who I'd argue would be leeches/vultures trying to extract their tax on the project). He's just commission 2-4 TBMs (tunnel boring machines, about ~$20MM/each), drop them in the ground, and have them start digging hyperloop tunnels.

If tunnel boring was that cheap, why is it costing the city of SF $1B to bore a tunnel ~1 mile?

Re: SpaceX Hyperloop Pod Competition

#65

Post by hughes »

imglorp wrote: post #52

I wonder what they will do about claustrophobia? > The capsule itself would need to be small—4.43ft (1.35m) wide and only 3.61ft (1.10m) high. No standing room No windows, pod inside a metal tube, seats reclined with minimal head room. There's no rational reason to panic in that position, but many people will not be comfortable. Video displays might help, but only to a point.

At 600MPH, I'm not sure I'd want to see the ground speeding past a few feet below...

Re: SpaceX Hyperloop Pod Competition

#66

Post by abduhl »

btilly wrote: post #54
toomuchtodo wrote: post #46

Earlier quoted context omitted.

Interested. TBMs are designed to drill through the earth, and then to wrap the tunnel walls with concrete blocks that are rated to last over 100 years. I'm curious if a TBM could cut through the earth and build hyperloop infrastructure behind it as well. As with everything, there are tradeoffs. Building above ground means land use issues, and the tunnel needs to be so small you can't stand in the hyperloop pods. Buil…

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?

Re: SpaceX Hyperloop Pod Competition

#67

Post by netfire »

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.

Would a Hyperloop system work well in a system with frequent stops, where you wouldn't be able to get up to full-speed because you needed to stop and the stops could disrupt other express traffic. Would you really be gaining that much over other traditional rail transportation options?

It seems like the strength of the Hyperloop is extremely fast travel over long distances. Personally, I think having a line between Las Vegas and Los Angeles would be awesome, as the traffic can be horrible on that route, especially on weekends and probably significantly affects traffic in LA in general. Its also around 100 miles less than the LA to SF route, through mostly undeveloped desert, so it could be a lot cheaper to build.

Re: SpaceX Hyperloop Pod Competition

#68

Post by CodeSheikh »

"Neither SpaceX nor Elon Musk is affiliated with any Hyperloop companies" Yet it is hosted on spacex.com. I love the project but I hate the legalities here. What does that mean? If something bad happens during operation then these aforementioned entities cant be held responsible.

Re: SpaceX Hyperloop Pod Competition

#69

Post by impish19 »

TeMPOraL wrote: post #23
lisper wrote: post #20

> SpaceX will construct a one-mile test track adjacent to our Hawthorne, California headquarters I'm not sure which would be the more remarkable achievement, getting the Hyperloop working, or obtaining the real estate to build a mile-long test track in Hawthorne .

They could use what I will call a rocket-estate crash coupling: 1. "Accidentally" crash a rocket near some properties there (far enough not to do any actual damage). 2. Wait for said property prices to crash.

You can't be serious.

Re: SpaceX Hyperloop Pod Competition

#70

Post by btilly »

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?

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.spacex.com/sites/spacex/files/hyperloop_alpha.pdf to confirm that this is a design factor the Elon explicitly considered.

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