KCRag Forum

Anthony_Hugo98 wrote: ↑Sun Oct 11, 2020 2:12 am I don’t know how probable it is, but figure I’d propose the idea. With the second iteration of the Boring Companies TBM in action in Las Vegas, and with them rapidly developing their 3rd generation of TBM technology, how likely would it be in the future for a lot of the monstrous interchanges in and around the downtown area go subterranean? I understand Mr. Musks goal with the Boring Company is to develop “3D road networks” with specific designs of transit technology, but the TBM tech that their developing could have further reaching effects. With massive cost reductions and faster drilling time, I feel their market further into the future will simply be tunneling and not so much their public transport tech. I could see them simply developing TBMs that can be sold to tunneling companies alone and reducing the cost to tunnel drastically. I know this is all pie in the sky right now, but figure if any group of people would humor my 6am airport thoughts it would be this group!

DaveKCMO wrote: ↑Sun Oct 11, 2020 8:19 am Talking to various people over the years that have looked at tunneling in KC, you have to go pretty deep for stability regardless of whether you're using a better technology to dig. I don't think TBC can change geology, they're just building smaller tunnels (12') and better TBMs.

A few other challenges to tunneling: land is cheap so the pressure to relocate above-ground highways isn't as intense (see North Loop), an unwillingness to go there by MoDOT (Kansas doesn't really need tunnels?), and the long-term maintenance cost (which Boring/Musk haven't really fixed).

Ultimately, this is another attempt to continue spending public dollars to build things we really don't need to effectively move people through cities. Musk has done a good job convincing people that an electric car on skates in a tunnel is the future of transportation while running companies that dig tunnels and sell electric cars.

Anthony_Hugo98 wrote: ↑Mon Oct 12, 2020 9:09 am
How much deeper would you need to go for stability? I remember seeing that both Boston and Seattle had fairly shallow tunnels for their subterranean interstates.

herrfrank wrote: ↑Tue Oct 13, 2020 2:18 pm The limestone layers, both the Winterset and the Bethany Falls groups, are thick, sturdy, and level. They would be the best candidates for deep tunnel boring through KC. However, midtown and downtown represent significant plateaux, requiring any north-south route that would pass under the east-west valleys at Turkey Creek or the KCTR r-o-w and also Brush Creek, to be deep in the limestone layer.

So if this were a tunnel for pedestrians, like a subway, you would be looking at 200-foot escalators to the surface in midtown and downtown. For an automobile tunnel, like the proposed Southwest Trafficway tunnel from the Plaza to the I-35 merger, the depth would be less of a problem, as the limestone emerges almost to ground level at those lower altitude formations.

phuqueue wrote: ↑Tue Oct 13, 2020 2:51 pm I don't understand what problem you are trying to solve by tunneling under KC for cars. We've spent more than enough money on car infrastructure already. If the issue really is just that monstrous interchanges are unsightly and/or a waste of space, we'd be better served by just ripping them out.

herrfrank wrote: ↑Tue Oct 13, 2020 2:18 pm The limestone layers, both the Winterset and the Bethany Falls groups, are thick, sturdy, and level. They would be the best candidates for deep tunnel boring through KC. However, midtown and downtown represent significant plateaux, requiring any north-south route that would pass under the east-west valleys at Turkey Creek or the KCTR r-o-w and also Brush Creek, to be deep in the limestone layer.

So if this were a tunnel for pedestrians, like a subway, you would be looking at 200-foot escalators to the surface in midtown and downtown. For an automobile tunnel, like the proposed Southwest Trafficway tunnel from the Plaza to the I-35 merger, the depth would be less of a problem, as the limestone emerges almost to ground level at those lower altitude formations.

Sani wrote: ↑Sun Oct 18, 2020 2:32 pm

herrfrank wrote: ↑Tue Oct 13, 2020 2:18 pm The limestone layers, both the Winterset and the Bethany Falls groups, are thick, sturdy, and level. They would be the best candidates for deep tunnel boring through KC. However, midtown and downtown represent significant plateaux, requiring any north-south route that would pass under the east-west valleys at Turkey Creek or the KCTR r-o-w and also Brush Creek, to be deep in the limestone layer.

So if this were a tunnel for pedestrians, like a subway, you would be looking at 200-foot escalators to the surface in midtown and downtown. For an automobile tunnel, like the proposed Southwest Trafficway tunnel from the Plaza to the I-35 merger, the depth would be less of a problem, as the limestone emerges almost to ground level at those lower altitude formations.

It's a shame this didn't happen in the early 50s, when we could have justified building a subway as creating a civil defense shelter.