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Has anyone seen the images inside the falcon 9 tunnel (same outside diameter as the rocket, lol)?

Quite small. I think that even with hyper loop vehicles we are talking about car sized payloads, not proper trains, right?

I would think that once it starts looking serious, government regulation will throw rather a lot of cold water on this. How many meters between escape stairs/ladders to the surface? Will such escape routes have to be ADA compliant? (Meaning wheelchair accessible, which means elevators)

I just texted a question about it to a buddy who is a lawyer, I'll let you know what he thinks.

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The "Tube" part of London Underground uses tunnels with inner diameter as low as 3.56 m. The largest trains running in them have capacity for 930 passengers.

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15 hours ago, YNM said:

Not really when your train have about the same top speed as a car down a HOV lane. Which is the problem the US have.

But the people on the train are not *in* the HOV lane, so that frees up space for other traffic.

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The 2 uses for the BC tubes right now is the car shuttle thing, or hyperloop. I got the impression for the latter that the vehicle would fill the evacuated tube.

 

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Risk scales to exit distance and ventilation, mostly fire is the concern. Germans use a guidance of 350m for exits, apparently. The car shuttle thing Musk pictured has on/off elevators probably at least that close, but I think you'd need stairs as well.

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14 hours ago, YNM said:

In places where you're close to the fault but not on it, it's probably the case. But on the fault itself, I doubt it. Almost all earthquakes that truly originates from a fault line (any type), those that ensures aftershocks, the ground does move. Although, Hollywood Fault only moves like, what, 0.6 mm each year or something, so even a 150 year earthquake may only move like 90 mm. Which, for something like Hyperloop vacuum chamber, could be "interesting".

Ah, I didn't see any numbers on slip right at the fault itself. (Due to a lazy search) Thanks for correcting me.

14 hours ago, YNM said:

For the record, I haven't see any tunnel in Hollywood's vicinity. LA Metro runs on elevated sections around the place.

EDIT : Scratch that - the LA Metro Red Line passes through the whole thing underground. Pretty much parallel to Musk's Hyperloop, just that his closes the I-405 while the Red Line closes the US 101. What I was referring to is the Gold Line which is actually closer to tram/light rail.

I wonder whether they figure the chances of a train being right at the fault during an earthquake is just low enough that it doesn't matter. If that's the case, then the sleds are no more dangerous. The hyperloop might be, depending on long it take for it to decelerate in emergency.

2 hours ago, StrandedonEarth said:

Whoops, I quoted you on that..

Evidence+of+earthquake+ground+movement+b

I'd say there's more than a few inches slip there...

(Fun Fact: The Universal Studios tour includes experiencing an earthquake in a subway station)

I said not to do that! :) 

Yep, it looks like there's lots of slip.

That photo brings up a couple of questions, though. First of all, why is it an S-curve, with both ends inline with each other? I imagine that a slip fault would just offset both ends, and leave a simple curve. Second of all, why is the ballast still straight? It seems like this might be a normal or thrust fault, which would explain the S-curve too; the rails have been shortened, causing them to buckle. 

Not to deny that it would be a problem for a tunnel, but it seems like tunnels aren't much more dangerous than other forms of transport during an earthquake.

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2 minutes ago, Mad Rocket Scientist said:

That photo brings up a couple of questions, though. First of all, why is it an S-curve, with both ends inline with each other? I imagine that a slip fault would just offset both ends, and leave a simple curve. Second of all, why is the ballast still straight? It seems like this might be a normal or thrust fault, which would explain the S-curve too; the rails have been shortened, causing them to buckle. 

I wondered about those things too. The jagged shadows confuse me as well. The image is deceptively narrow which makes it hard to see what really happened to the ballast around the displacement. A thrust fault hadn't occurred to me but certainly makes sense.

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Displacement of crust can easily reach several meters (10s of feet) during catastrophic earthquakes along active fault lines.

See USGS (United States Geological Survey) page for exact data of the San Andreas fault, if i remember correctly the plates move at 5cm relative movement per year which can build up a tremendous tension.

As to tunnels: it is less (but of course also) the earthquake itself (wave propagation) but the possible mobilisation of watery sediments that imposes danger to underground structures. That can dislocate a huge body of sediments in one single event. Maybe USGS has info on that as well, i am too lazy to look it up :-)

Edit: the picture is absolutely real, it is not even soooo much displacement. Looks as if it was compressed ?

Edited by Green Baron
Easily canceled. Can reach suffices :-)

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I think the larger concern is more mundane safety. What if a battery powered vehicle has a fire in the tunnel, or a sudden stop that forces all the vehicles behind to also stop?

My friend thinks that regulatory concerns would certainly require a risk mitigation strategy of some kind that is likely expensive. Not impossible, but a real concern.

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6 minutes ago, Green Baron said:

Edit: the picture is absolutely real, it is not even soooo much displacement. Looks as if it was compressed ?

OK, in that case then I agree that buckling is the only explanation. That's definitely not a picture of a sideways slip plane.

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3 hours ago, StrandedonEarth said:

Whoops, I quoted you on that..

Evidence+of+earthquake+ground+movement+b

I'd say there's more than a few inches slip there...

I'm not sure, but surely that's not sun kink ? In earthquakes the rails would just near-completely wander off to one side or something, unless some weird resonance allows the one imaged to occur. Soil and ballast (loose rocks) in earthquake are like loose sand in normal conditions I presume (they'll flatten out and things move above them or something).

Also, frost heaving do much more damage than that. Though they happen over winter... damit i lost the document i downloaded ! it highlight the behavior and the damage permafrost do.

2 hours ago, tater said:

Risk scales to exit distance and ventilation, mostly fire is the concern. Germans use a guidance of 350m for exits, apparently. The car shuttle thing Musk pictured has on/off elevators probably at least that close, but I think you'd need stairs as well.

How do you evacuate from a vacuum tube ? Turn on the vacuum machine ? :P

1 hour ago, Mad Rocket Scientist said:

I wonder whether they figure the chances of a train being right at the fault during an earthquake is just low enough that it doesn't matter. If that's the case, then the sleds are no more dangerous. The hyperloop might be, depending on long it take for it to decelerate in emergency.

... 

Not to deny that it would be a problem for a tunnel, but it seems like tunnels aren't much more dangerous than other forms of transport during an earthquake.

I guess bigger problems with Hyperloop is the vacuum itself. No breach is allowed, if any occurs it has to be isolated. Maglev trains in tunnels in an earthquake... well, time to ask the Japanese I suppose.

2 hours ago, mikegarrison said:

But the people on the train are not *in* the HOV lane, so that frees up space for other traffic.

Well apart that HOVs can only be filled with busses and cars... have you not seen one ? Fantastically just like your own separate highway.

Edited by YNM

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Yeah, they hyperloop thing is a whole different issue. Fire obviously not a concern... in the tube.

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21 hours ago, YNM said:

I'm not sure, but surely that's not sun kink ? ...

Alright, it can happen in an earthquake, but Alpine fault in NZ moves 30mm/year, which is 50x more than Hollywood fault or 10x more than the whole San Andreas fault. Clearly some big difference. But in the case of an actual earthquake, the damage might be the same.

Edited by YNM

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8 hours ago, YNM said:

I guess bigger problems with Hyperloop is the vacuum itself. No breach is allowed, if any occurs it has to be isolated. Maglev trains in tunnels in an earthquake...

That's why I disbelieve in vacuum pipetrains. Any leak - and several trains feel sick,

Ekranoplan trains look more convincing for me. No vacuum, no friction, no pressurizing,
(I would add a anti-animal glass tube around, of course).
 

9 hours ago, tater said:

This explains much. In their Southern Hemisphere they have all things upside down. Railways are strange, too.

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11 hours ago, YNM said:

... 10x more than the whole San Andreas fault ....

It's about the same horizontal movement as that of the plates at San Andreas fault. The latter moves between 1 and 2 inches/yr, that are 25-50mm. It is not a continuous movement. Shear forces build up over time and at some point the force exceeds what the crust can take, so the forces release in a single or a series of events. It is impossible to predict how and when the next release of shear force will happen, any attempts to do so have failed.

Spreading rates at ocean ridges and compression near subduction zones can be much more (e.g. 15cm/year or 6 inches in the eastern pacific). The material must go somewhere ...

Edited by Green Baron

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On 7/21/2017 at 6:00 PM, YNM said:

Not really when your train have about the same top speed as a car down a HOV lane. Which is the problem the US have.

I told you I prefer commuting by train, and you told me "not really"? Wow, you know my own preference better than I do? That's amazing.

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I only get to ride trains as entertainment or travel, but I'd certainly prefer to read, etc, to driving in traffic. That said, I think that soon self driving vehicles would make the two the same. Socializing would obviously require a sort of self driving carpool.

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9 hours ago, mikegarrison said:

I told you I prefer commuting by train, and you told me "not really"? Wow, you know my own preference better than I do? That's amazing.

Sorry if I have insulted you, but based on the evidences I have, in wider parts of US traffic jams happens only in peak times. This means that utilization of public transport also only happens in peak times. Contrasts to what happens in "full-fledged" conurbations where movement of people is still significant outside peak times during the day; in those place you want to have public transport every time consistently. For example, I don't consider @tater's home conurbation among the full-fledged ones; last check (08:30 UTC+7) shows the interstates around Albuquerque, NM to be mostly empty, and only LA and SFO shows considerable traffic. Again, when you have a network and a point-to-point option, where the maximum speed is almost equal or better in the point-to-point one, trust me, I'd drive. If you have something like this however... (or well, look at LA or SFO).

There's a reason why our 1 USD commuter train in the capital is brimmed to the lid until good hours after peak times while most of yours becomes a burden.

 

EDIT : On the point of Hyperloop, I know it have to compete with airplanes between SFO and LAX; but doing that in the same 100 USD budget max, I doubt it. Most flights between those two cities are less than 1h30m, and the commute to/from the center each is around (or less than) 0h30m. That's 2h30m max journey time. The distance between LA and SFO on the road is 380 mi; with a train of average spees 100 mph (top speed should be 120 mph or higher), the journey is done in 4h. Realistic comparison for Edinburgh - London shows about the same thing, the trains take 5h40m however. Not ideal, but if they could make it for the price somehow, maybe they could have it better.

Edited by YNM

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For me, there is only one argument against robo-cars, robo-trains and robo-tunnels: presence of unpredictable human drivers in some cars.

Remove the root of the evil (take the grenade from the ape), and any traffic will be absolutely safe and smooth.

Then any such project will look either possible or unnecessary due to disappearing of the problem.

Edited by kerbiloid

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5 hours ago, YNM said:

Sorry if I have insulted you, but based on the evidences I have, in wider parts of US traffic jams happens only in peak times. This means that utilization of public transport also only happens in peak times. Contrasts to what happens in "full-fledged" conurbations where movement of people is still significant outside peak times during the day; in those place you want to have public transport every time consistently. For example, I don't consider @tater's home conurbation among the full-fledged ones; last check (08:30 UTC+7) shows the interstates around Albuquerque, NM to be mostly empty, and only LA and SFO shows considerable traffic. Again, when you have a network and a point-to-point option, where the maximum speed is almost equal or better in the point-to-point one, trust me, I'd drive. If you have something like this however... (or well, look at LA or SFO).

There's a reason why our 1 USD commuter train in the capital is brimmed to the lid until good hours after peak times while most of yours becomes a burden.

 

EDIT : On the point of Hyperloop, I know it have to compete with airplanes between SFO and LAX; but doing that in the same 100 USD budget max, I doubt it. Most flights between those two cities are less than 1h30m, and the commute to/from the center each is around (or less than) 0h30m. That's 2h30m max journey time. The distance between LA and SFO on the road is 380 mi; with a train of average spees 100 mph (top speed should be 120 mph or higher), the journey is done in 4h. Realistic comparison for Edinburgh - London shows about the same thing, the trains take 5h40m however. Not ideal, but if they could make it for the price somehow, maybe they could have it better.

Dude, I expressed a PERSONAL PREFERENCE and you continue to mansplain to my why my own preference can not really be my preference.

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26 minutes ago, mikegarrison said:

Dude, I expressed a PERSONAL PREFERENCE and you continue to mansplain to my why my own preference can not really be my preference.

Okay, as far as I can tell, he/she understands your preference, and that, given the area you live in, it is better to take the train. He/she was trying to explain that it is not the same in all places, so that you can understand that sometimes other forms of transport are more effective. They were just trying to help you function in the conversation.

Apologies for going off topic, but I haven't being following things too closely. One question- is the 'verbal approval' significant?

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2 hours ago, mikegarrison said:

Dude, I expressed a PERSONAL PREFERENCE and you continue to mansplain to my why my own preference can not really be my preference.

Well, go on then I suppose. I wasn't talking about your preference. I was talking the thinking of an average joe, not you.

I *also* like going on trains as it's much clearer than the busses that we have here. But intercity trains, well you need to plan in advance and such so I don't go on it quite as often (or as liking as commuter ones). Haven't get a go on intercity busses, my father says it's quite good as there's more comfort in the seating and cheaper than intercity trains. I have a driving license for cars but I don't have a car in hand (and don't need them) - only using motorcycles at the time.

Maybe if you could copy yourself millions of time the passenger railways in US will start going rich. :wink:

Edited by YNM

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7 hours ago, kerbiloid said:

For me, there is only one argument against robo-cars, robo-trains and robo-tunnels: presence of unpredictable human drivers in some cars.

Remove the root of the evil (take the grenade from the ape), and any traffic will be absolutely safe and smooth.

Then any such project will look either possible or unnecessary due to disappearing of the problem.

That self-driving vehicles need to deal with poor human drivers is in fact a good thing as it results in better driving systems. Even minus people behind the wheel, they would need to deal with people in the streets, and other unpredictable situations.

I still think that self-driving will be very disruptive to even mass transit. In some distance regimes, mass transit will still make loads of sense (commuting from a 'burb to a city), but within a city, particularly in the spread out US West, door to door will kill mass transit completely.

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