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The Boring Company's First Tunnel Is All Dug Up (arstechnica.com)
Elon Musk has tweeted images of his tunnel-boring machine with the caption "Congratulations @BoringCompany on completing the LA/Hawthorne tunnel! Cutting edge technology!" The update comes a couple weeks after Musk showed off the Boring Company's LA tunnel and said it was "on track" for an opening party on December 10th. Ars Technica reports: The tunnel appears to end at what The Boring Company calls "O'Leary Station," which is located on a piece of commercial property that The Boring Company purchased in Hawthorne. This location is close to, but not the same as, the location for which The Boring Company recently received approval to build a tunnel entrance within a residential garage. "O'Leary Station" references a SpaceX/Boring Company employee who recently passed away. The Hawthorne tunnel is just a test tunnel for The Boring Company, which also plans to complete a second, 3.6-mile, one-way tunnel from Los Angeles Metro to Dodger Stadium. Eventually, the company wants to dig a tunnel in Chicago between O'Hare International Airport and the city's downtown.
I think he'll only be truly congratulated when a tunnel full of these people gets buried with no hope of recovery during the next significant seismic event.
The diesel engine in confined space will asphyxiate the workers. Supplying air and taking away the exhaust is a very complex operation, adding to the costs. Especially on long tunnels.
Having said that, competition will catch up quickly. They can house the diesel engines at the entrance or tap into the grid and send power by cables to the drill head. Not sure how feasible it would be though. Also looks like the boring company is planning on autonomous self driving tubs to take the tilings away and to bring fresh batteries. This too could reduce the cost of tunneling. Again, other can easily copy.
Tunneling has changed for ever. Whether The Boring Company will get a big slice of the market and windfall, I am not sure. But 20 years from now, all tunnel boring ops will be like what the boring company is doing now.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Ok lets look at the so called improvements one by one:
Continuous casing - I'm assuming by this you mean concrete. This method can only be used when the ground is pretty strong and self supporting. That means rock - not soil or shallow tunnels. The concrete takes a few days to build up sufficient strength and you can't use the lining to push the TBM off of which means side grippers which further means a strong rock environment. Pre-cast concrete or iron rings give immediate ground support / cover for the TBM crew as well as a solid base to propel the TBM from. You can either pour the concrete in an annular ring or spray, both of which potentially are messy compared to installing pre-cast rings and not necessarily faster. Yes you can use pipe jacking techniques where the casing is added at the back end and the thrust applied there, but I wouldn't call that continuous.
Hot swappable discs - as by definition the discs installed are all required to excavate the complete face area, if any are withdrawn from service you have incomplete excavation. You could only possibly do this by having overlapping cutter heads, which would duplicate costs for negligible gain, considering typical downtime for cutter heads is a few hours every 3 days or so. A period which is used for general maintenance as well.
Faster head speeds - the cutting ability of a cutting disc is dictated by the rotational head speed and pressure applied at the cutting edge. Too much pressure/speed and you get accelerated wear and too much heat generated which also leads to accelerated disc wear. The best material we have is tungsten carbide mounted in a ceramic matrix. Unless some fantastic cheap material is developed that can resist the heat and has the requisite physical resilience and hardness, then we will be still be using TC.
Tunnelling has a few well defined parameters, which are logistics in and out and matching the cutting technology to the ground conditions. Nothing I've seen from the Boring Company's released information suggests any breakthrough advances in any major area.
No, no we can't.
Surface trains already kill a lot of people (and animals) every year, and to add more surface lines requires eminent domain and the destruction of existing buildings and habitats. People die on the order of daily at at-grade railroad crossings. We simply can't improve our rail connections between cities at the surface level. Sure, we could elevate all of the tracks, but that's expensive and really shitty to live near.
Train tracks are a significant barrier for everyone, and the more trains you have, the more of a barrier they become.
Going underground gets rid of all of these problems. If The Boring Company can really get tunnel costs down as far as they think they can, it will indeed revolutionize transport. And if it turns out that people aren't interested in traveling in a high-speed coffin underground, that's fine. We can still replace a lot of our trucking and train shipments, which will free up a lot more space on the surface for the humans.
Velociraptor = Distiraptor / Timeraptor
In many cases, tunnel boring machines are custom built and buried in a side channel once construction is complete...
https://untappedcities.com/201...
There are hundreds of such machines buried across the world. They are just written off as part of the construction expense, as no one really wants the cost of extracting them overground.
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