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The Boring Company FAQ

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Re: The Boring Company FAQ

#131

Post by prostoalex »

erentz wrote: post #74
Animats wrote: post #61

So, the key ideas are: - Smaller diameter tunnels. 14' is suggested. This is slightly larger than the deep London Tube lines. - Electrically powered TBMs. Those exist. However, often the business end of the machine is hydraulically powered. Musk is probably thinking of going all electric, at least for the cutter head. After all, he has lots of experience with high-torque electric motors. - Do cutting and tunnel ring…

Yeah this is all very odd and everyone is lapping it up. He claims to want to reduce tunneling costs by a factor of 10, but starts by quoting a very high benchmark of $1 billion per mile which is quite easy to beat. Then he reduces diameters to something much smaller than all the expensive mega projects, into the range of something where technology is well established and costs are already 1/10th of his quoted $1 bil…

> But then for some reason the solution has to involve putting cars into these tunnels. If what he thinks he is on to is viable with cars in those tunnels, it's even more viable with trains carrying 1,000 passengers each coming every 3 minutes. So why aren't we building these subways with trains?

Because with trains you never build just a tunnel - there are train stations, escalators leading in and out, ticketing booths/machines, electrical work to power all that fun stuff, connectors to existing depots so that maintenance workers can come and service the cars and the engines.

His idea is closer to Madrid, which has dug tunnels to relieve the city streets of the traffic. The tunnels themselves are very unassuming and look like onramps and underground parking garage entrances.

Re: The Boring Company FAQ

#132

Post by objclxt »

CodeWriter23 wrote: post #125
erentz wrote: post #74

Earlier quoted context omitted.

Yeah this is all very odd and everyone is lapping it up. He claims to want to reduce tunneling costs by a factor of 10, but starts by quoting a very high benchmark of $1 billion per mile which is quite easy to beat. Then he reduces diameters to something much smaller than all the expensive mega projects, into the range of something where technology is well established and costs are already 1/10th of his quoted $1 bil…

He's trying to hit a price point. We're not completely allergic to the $20M freeway bridge that's about 100ft long, and comes with heavy upkeep costs over the long term. So, $100M per mile with Upkeep Lite™ sounds good when making conversation about the topic. Also the $1B/mile is the cost of the Purple Line extension in Los Angeles. Worst case cost no doubt. A real figure nevertheless.

> So, $100M per mile with Upkeep Lite™ sounds good when making conversation about the topic. Also the $1B/mile is the cost of the Purple Line extension in Los Angeles. Worst case cost no doubt. A real figure nevertheless.

The figure is way out. Crossrail in London has a $20 billion total budget (£15b GBP), with 26 miles of tunnel[1]. But the tunnel is only part of the project, several billion is being spent on new regular track and station rebuilds, so the tunneling figure is really closer to $15 billion.

That's about $570 million per mile, but the Crossrail tunnels are just shy of 50% bigger in diameter than what Musk wants to build (20.5' vs 14'). And as the FAQ says, "reducing the diameter in half reduces tunneling costs by 3-4 times".

LA's tunnel might be costing $1B/mile, but how much of that cost is actual construction versus bureaucracy and mismanagement?

[1]: http://www.crossrail.co.uk/construction/

Re: The Boring Company FAQ

#133

Post by CodeWriter23 »

ProAm wrote: post #95
Erik816 wrote: post #87

Earlier quoted context omitted.

Isn't that still taking roads 3D?

What's more expensive and has long term track record success?

Pay today or pay tomorrow. I don't think it is an outlandish thought IF $100M/mile tunnels are achieved that the TCO for an elevated roadway will be higher. Elevated roadways have to be replaced eventually. Tunnels are more durable, look at the Holland Tunnel for example, 89 years old and no need for replacement in sight. And it's $48M price tag would be $3.3B today for 1.62 miles.

Re: The Boring Company FAQ

#134

Post by astrocat »

tedsanders wrote: post #29
astrocat wrote: post #20

Earlier quoted context omitted.

> I'd like to see more details about edge case scenarios. The thing is, we're all MUCH more comfortable with the danger we're familiar with, than the danger we're unfamiliar with. Imagine if planes were just being introduced today - what are the edge case scenarios? What happens if there's mechanical failure at 30,000 feet? What happens if there's turbulence, lightning, birds, volcanic ash? What happens if the pilot…

>I'm not saying the dangers of new tech aren't important - they're very important; but keep in mind that while the idea of suffocating after a crash or malfunction in a hyperloop tube/tunnel will feel significantly more perilous than any misfortune that may befall you on a plane simply because a plane's risks are now familiar . Without understanding edge case scenarios, we cannot make claims like these. Maybe these t…

> Without understanding edge case scenarios, we cannot make claims like these.

Actually, this claim isn't based on any particulars of any scenario. It's simply a common human cognitive pattern. We will readily accept a familiar risk over an unfamiliar risk, even if the unfamiliar risk is less risky. We all readily jump in our cars every day despite the statistical fact that car-miles are quite deadly when compared with alternatives like bus-miles, train-miles, or plane-miles.

We're also likely to underestimate the magnitude of a risk when we have some perceived sense of control. Most drivers believe they are above average - so the risk of accidents is undervalued (due to ego). On planes, the risk of harm is overvalued because passengers have no sense of control in failure scenarios.

Like I said, we SHOULD understand how new tech can fail. We ALSO need to be careful about the biases with which we approach a new technology and aware of what we're expecting from it. We tend to overvalue the ways in which a new tech can introduce unfamiliar harm, while undervaluing the ways in which a new tech can remove familiar harm that's currently taken for granted (hence, undervalued). This presents policy/planning problems that can inhibit introduction of society-benefiting innovations. This does not mean that conservative approaches to deploying new tech are wrong - far from it: conservative adoption is responsible - it simply points out that our natural human biases tend to maintenance of the status quo.

My point is that, quite simply, we need to be as realistic and comprehensive in our establishment of the benefits a new tech could introduce, as well as the risks, in order to have a balanced perspective of its overall value.

Re: The Boring Company FAQ

#135

Post by rocky1138 »

dennyabraham wrote: post #31

An automated electric tunneling system that can recycle material into building components sounds incredibly useful to prep mars for colonies.

Have you ever read up on Mars lava tubes? The idea of using them to start colonies makes a lot of sense to me.

Re: The Boring Company FAQ

#136

Post by schiffern »

easilyBored wrote: post #12
schiffern wrote: post #2

> What do you do with all that dirt? >... The Boring Company is investigating technologies that will recycle the earth into useful bricks to be used to build structures... These bricks can potentially be used as a portion of the tunnel lining itself, which is typically built from concrete. Since concrete production accounts for 4.5% of the world’s greenhouse gas emissions, earth bricks would reduce both environmental…

I have seen ~3 decades old earth bricks (granted, uncompressed) and it's not pretty. Maybe compression and hydro-isolation does wonders.

>~3 decades old earth bricks (granted, uncompressed) and it's not pretty

No surprise there. CSEB is an entirely different material from regular old compressed earth block, which itself is entirely different from uncompressed earth. Squeezing out the empty space and adding a binder (cement) makes it all one solid piece as strong as concrete. Uncompressed earth is just... dirt.

It's like saying, "Concrete roads won't work. How do we know? Because gravel is an ingredient of concrete, and gravel roads suck."

Re: The Boring Company FAQ

#137

Post by objclxt »

sAuronas wrote: post #89
discodave wrote: post #48

The old strategy of hiding your outlandish claim in an assertion in the first sentence! "To solve the problem of soul-destroying traffic, roads must go 3D" The word "must" is a very strong one here, there are other options: * Reduce the amount of travel that people need to do (remote work, online shopping). * Reduce the density of cities (enabled by remote work or longer commutes with better internet access). * Incre…

Cities like LA will become denser over time. It might seem counterintuitive but increasing density alleviate traffic (people walk). You can't clean a hotel or flip a burger remote. Public transit has failed to solve the problem despite a 100-year head start. Cycling... in LA... I don't think the Boring Company is trying to solve the gridlock. They will, however, provide an option for those who can afford to pop down…

> Public transit has failed to solve the problem despite a 100-year head start.

So the question here really is "which would improve LA more: tunnels that carry trains, or tunnels that carry carts that hold single cars?"

There is plenty of strong evidence that shows adding additional road capacity increases overall traffic. I'm not sure that adding ways to move cars around faster wouldn't have the same impact, versus a train.

Re: The Boring Company FAQ

#138

Post by Turing_Machine »

Fricken wrote: post #90
econnors wrote: post #65

Earlier quoted context omitted.

I think you're right that stops will be longer, but it's my understanding they'll also be less frequent and they'll cover greater distances than a regular subway track (in say, NY). So you'll end up getting there faster and not have the stress of driving in traffic.

For a conventional subway at rush hour, there's 1000s of people getting on or off every hour at any given station, which isn't feasible if you're only loading a dozen people at a time. The alternative being to build proper underground stations, which are a big part of that 'billion dollars per mile' subway construction cost. And this reminds me of Musk's Hyperloop whitepaper, where he estimated it would cost 10 billi…

Elevator engineers sometimes handle this problem by having "express" elevators that travel between distant floors and "local" elevators that operate between nearby floors.

That avoids the need for big central stations (other than the ground-floor lobby, of course, but there's no way around that for a building -- a street transport system isn't limited to a single point of entry).

Re: The Boring Company FAQ

#139

Post by tedsanders »

Turing_Machine wrote: post #130
tedsanders wrote: post #29

Earlier quoted context omitted.

>I'm not saying the dangers of new tech aren't important - they're very important; but keep in mind that while the idea of suffocating after a crash or malfunction in a hyperloop tube/tunnel will feel significantly more perilous than any misfortune that may befall you on a plane simply because a plane's risks are now familiar . Without understanding edge case scenarios, we cannot make claims like these. Maybe these t…

People have been building tunnels for a lot longer than they've been building planes. They are extremely well-understood. The innovation here is in digging the tunnels, not their operation.

Then by all means, go ahead and answer @atarian, not me. His or her questions didn't seem straightforward to me, but perhaps you or someone else knows better.

Re: The Boring Company FAQ

#140

Post by Tiktaalik »

>A large network of road tunnels many levels deep would fix congestion in any city, no matter how large it grew (just keep adding levels).

A large network of highways many lanes wide would fix congestion in any city, no matter how large it grew (just keep adding lanes).

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