4 ms·

I think transport would be infinitely worse in a linear city. In a traditional street network, there are many ways to get from A to B and one link being unavai

I think transport would be infinitely worse in a linear city. In a traditional street network, there are many ways to get from A to B and one link being unavailable is not the end of the world. Forcing everyone onto essentially the same street is guaranteed to cause both high fragility and high congestion, since everyone has to squeeze into the same line.

plantwallshoe 4y ago
If it’s 200m wide you could probably get 6-8 trains running parallel.
Double_a_92 4y ago
But if you knew that everyone has to use that same street, you could dimension it properly because you know exactly what to expect.
bayesian_horse 4y ago
There's no need to have only one line to connect everything, even in a linear structure. It's still about the topology. At the simplest there would be one line connecting from end to end, which should be the fastest and the one with the fewest stops. But then you have smaller lines, travelling in their own tubes, connecting local areas. That way you can travel between any two points relatively fast and avoid congestion. You can build redundancy into this system. But also, it's not a catastrophe on a normally 20 minute trip if there is blocked section and you have to walk a few minutes, take a local connection to bypass the blockage and then go on. Happens to me all the time... The big benefit in a linear city is that the transport pods never need to turn around. You also don't need to manufacture curved rails or things like that. You can build structures like that in a "2D" city, but it's harder.
- amluto 4y ago
  In 2D, you can build a grid of straight line railways. Riders transfer zero or one times. Cost scales proportionally to area (and hence population) assuming constant density. Time between two random points scales as sqrt(size). Ridership on a given rail segment scales like sqrt(size), which may be tolerable. In 1D, you can build a linear railway. Cost scales proportionally to length (and hence population) if you assume that the the railway merely needs to get longer as population grows, but this gives a system where ridership on a given rail segment scales linearly with population, which is much worse. Time between two random points also scales linearly with population. The added costs associated with improving performance given the worse scaling seem likely to blow the whole thing up.
  - rdsubhas 4y ago
    Remember, this is still a 2D project. The second dimension is up! Instead of XZ axes, it's XY. Your point about length is true, but about population scale might not, because it's still in 2D. There are still ways to segregate tracks.
    - bobthepanda 4y ago
      Vertical poses a lot more problems than horizontal, though. As a general example, fire generally makes it unsafe to operate anything above or below.
  - spywaregorilla 4y ago
    > In 2D, you can build a grid of straight line railways. Riders transfer zero or one times. Cost scales proportionally to area (and hence population) assuming constant density. Time between two random points scales as sqrt(size). Ridership on a given rail segment scales like sqrt(size), which may be tolerable. I doubt this would work. Cities don't do this for a reason. Transit lines get built according to transportation needs, not mathematical coverage of the space. You have pockets of housing that need to get to pockets of commerce. You can't practically run transit cars connecting [0,0] and [end, 0].
    - bobthepanda 4y ago
      A lot of big city metro networks look like grids in the city center, or effectively function as such. Farther out the grid is plugged in by bus.
      - spywaregorilla 4y ago
        Can you provide an example of a city with a grid-like metro? I know many grid like cities. I cannot think of any grid like metros.
        bobthepanda 4y ago
olalonde 4y ago
Most people in Hong Kong don't own a car, it's just not necessary due to the high density. This city is expected to to be ~15 times as dense as Hong Kong.
- bobthepanda 4y ago
  You don’t have to be in a car to experience street congestion. Hong Kong has plenty of areas with bus, metro or pedestrian congestion. If everyone in Hong Kong was shoved into one train line, it would also be congested.
- panick21_ 4y ago
  You don't need high density to not need a car. Its totally possible to design cities where most people don't need cars that are not full of huge towers. The idea that car-free or very limited car is only possible if you have absurd density is false. Its totally possible to have nice suburbs that are totally walkable and don't require a car for 90% of the population.
rdsubhas 4y ago
Remember, this is still a 2D project. The second dimension is up! Instead of XZ axes, it's XY. There are still multi layer travel options available. And some previously unthinkable possibilities (e.g. moving walkways like the kind you see in airports, for short distances within a block – or different colored trains on different levels like ground/underground) are still possible.

plantwallshoe 4y ago

If it’s 200m wide you could probably get 6-8 trains running parallel.

Double_a_92 4y ago

But if you knew that everyone has to use that same street, you could dimension it properly because you know exactly what to expect.

bayesian_horse 4y ago

There's no need to have only one line to connect everything, even in a linear structure. It's still about the topology. At the simplest there would be one line connecting from end to end, which should be the fastest and the one with the fewest stops. But then you have smaller lines, travelling in their own tubes, connecting local areas. That way you can travel between any two points relatively fast and avoid congestion. You can build redundancy into this system. But also, it's not a catastrophe on a normally 20 minute trip if there is blocked section and you have to walk a few minutes, take a local connection to bypass the blockage and then go on. Happens to me all the time... The big benefit in a linear city is that the transport pods never need to turn around. You also don't need to manufacture curved rails or things like that. You can build structures like that in a "2D" city, but it's harder.

amluto 4y ago
In 2D, you can build a grid of straight line railways. Riders transfer zero or one times. Cost scales proportionally to area (and hence population) assuming constant density. Time between two random points scales as sqrt(size). Ridership on a given rail segment scales like sqrt(size), which may be tolerable. In 1D, you can build a linear railway. Cost scales proportionally to length (and hence population) if you assume that the the railway merely needs to get longer as population grows, but this gives a system where ridership on a given rail segment scales linearly with population, which is much worse. Time between two random points also scales linearly with population. The added costs associated with improving performance given the worse scaling seem likely to blow the whole thing up.
- rdsubhas 4y ago
  Remember, this is still a 2D project. The second dimension is up! Instead of XZ axes, it's XY. Your point about length is true, but about population scale might not, because it's still in 2D. There are still ways to segregate tracks.
  - bobthepanda 4y ago
    Vertical poses a lot more problems than horizontal, though. As a general example, fire generally makes it unsafe to operate anything above or below.
- spywaregorilla 4y ago
  > In 2D, you can build a grid of straight line railways. Riders transfer zero or one times. Cost scales proportionally to area (and hence population) assuming constant density. Time between two random points scales as sqrt(size). Ridership on a given rail segment scales like sqrt(size), which may be tolerable. I doubt this would work. Cities don't do this for a reason. Transit lines get built according to transportation needs, not mathematical coverage of the space. You have pockets of housing that need to get to pockets of commerce. You can't practically run transit cars connecting [0,0] and [end, 0].
  - bobthepanda 4y ago
    A lot of big city metro networks look like grids in the city center, or effectively function as such. Farther out the grid is plugged in by bus.
    - spywaregorilla 4y ago
      Can you provide an example of a city with a grid-like metro? I know many grid like cities. I cannot think of any grid like metros.
      - bobthepanda 4y ago

olalonde 4y ago

Most people in Hong Kong don't own a car, it's just not necessary due to the high density. This city is expected to to be ~15 times as dense as Hong Kong.

bobthepanda 4y ago
You don’t have to be in a car to experience street congestion. Hong Kong has plenty of areas with bus, metro or pedestrian congestion. If everyone in Hong Kong was shoved into one train line, it would also be congested.
panick21_ 4y ago
You don't need high density to not need a car. Its totally possible to design cities where most people don't need cars that are not full of huge towers. The idea that car-free or very limited car is only possible if you have absurd density is false. Its totally possible to have nice suburbs that are totally walkable and don't require a car for 90% of the population.

rdsubhas 4y ago

Remember, this is still a 2D project. The second dimension is up! Instead of XZ axes, it's XY. There are still multi layer travel options available. And some previously unthinkable possibilities (e.g. moving walkways like the kind you see in airports, for short distances within a block – or different colored trains on different levels like ground/underground) are still possible.