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Mexico building rail rival as water shortages drain Panama Canal

japantimes.co.jp

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Re: Mexico building rail rival as water shortages drain Panama Canal

#81

Post by adrianmonk »

bdcravens wrote: post #49
dessimus wrote: post #45

Earlier quoted context omitted.

I'm no engineer, but I would not imagine that the Panamax ships are built to handle that kinda of stress while still loaded with cargo. The ships are designed to have the weight of itself and its cargo spread out pushing out against the displaced water pushing back on the hull rather evenly and not a handful of highly concentrated points.

Just build a giant bathtub and tow that /s

Imagine the hilarity if the giant bathtub train car derails and tips over. Has there ever been a train wreck that caused a flood? If not, there's a first time for everything.

There's also the possibility that you get 100 km inland and then the bathtub springs a leak. Not a good situation if the ship's structural integrity depends on the water in the tub.

Re: Mexico building rail rival as water shortages drain Panama Canal

#82

Post by albert180 »

Animats wrote: post #79
bilsbie wrote: post #5

Surely this is a mega project: but naively, what if we built say ten parallel railways 10 ft apart and moved cargo ships over the rails? Or this guy only needs to be scaled up 10X to do the job. Not outside the realm of imagination? https://en.m.wikipedia.org/wiki/Crawler-transporter I know the ships are huge and it shouldn’t be feasible but it would be interesting to run the numbers. Edit. Actually if my math is rig…

There's been a rail line there for a century. It's just being improved. It's the port facilities that need major expansion. Why lift ships? Containers are designed to be easily loaded, unloaded, and carried on various vehicles.

Some people love reinventing rail, but just worse, more expensive and less efficient.

Re: Mexico building rail rival as water shortages drain Panama Canal

#83

Post by albert180 »

sitharus wrote: post #37
melling wrote: post #32

Earlier quoted context omitted.

How fast can modern freight trains run? If they’re twice as fast as cargo ships, maybe we need fewer tracks? And a longer land route?

The Ever Given has a maximum speed of 23kt / 42km/h and carries 20,124 TEU or approx. 7660 54-ft containers. Rail figures are harder to find, but a reasonable guess based on what I can find seems to be 400 containers per train if the loading gauge permits double stacking containers. Speeds over 100km/h are easily achievable on railways without at-grade crossings. So one ship could easily require ten trains to move al…

Freight trains run usually at 80-120km/h on railways with at-grade-crossings (for higher speeds you would need better brakes, and more energy which doesn't really make sense for freight). At least in Europe you only need to eliminate at-grade-crossings if you want to run trains over 160km/h

Re: Mexico building rail rival as water shortages drain Panama Canal

#84

Post by albert180 »

loceng wrote: post #80
albert180 wrote: post #78

Earlier quoted context omitted.

Because it's stupidly expensive boring a Tunnel when you can just do it on the surface. Also Railway lines take up considerably less space than every Street. Weather also rarely impacts rail

Maybe on the surface (pun intended) it appears stupidly expensive in comparison, but I bet if you actually put a value to all of the positives then the cost would at minimum be at par. With tunnels you can also go 3D, you could go 100 tunnels deep - stacked - increasing capacity on the same line as needed; something Elon points out as part of the traffic congestion problem is that cities went 3D (skyscrapers) but tra…

You build that route through nothing. There is no need for tunnels, and I don't see any positives, that you couldn't remediate much cheaper. For animal movement you can just build huge animal bridges every few hundred meters. Weather is rarely a problem for train operations, tunnels create also a whole lot of new "Negatives". You need evacuation systems, ventilation systems, maintenance etc...

Re: Mexico building rail rival as water shortages drain Panama Canal

#85

Post by mr_toad »

wolverine876 wrote: post #71
bilsbie wrote: post #5

Surely this is a mega project: but naively, what if we built say ten parallel railways 10 ft apart and moved cargo ships over the rails? Or this guy only needs to be scaled up 10X to do the job. Not outside the realm of imagination? https://en.m.wikipedia.org/wiki/Crawler-transporter I know the ships are huge and it shouldn’t be feasible but it would be interesting to run the numbers. Edit. Actually if my math is rig…

It apparently was done in ancient Greece. Look up the Diolkos of Corinth.

Triremes had to be regularly lifted out of the water or they would become waterlogged. They were surprisingly light weight, and could actually be carried onto a beach by their crew.

Re: Mexico building rail rival as water shortages drain Panama Canal

#86

Post by reactordev »

jefftk wrote: post #63
reactordev wrote: post #46

Earlier quoted context omitted.

So clearly they don’t know what they are talking about. Any sailor would tell you, you don’t go above and below 55 degrees. Granted these are steel container ships but the seas don’t care. What’s one or two lost containers of goods? They sit just below the water surface for the next vessel to crash into. The Panama Canal has two paths. Only one can be used for container ships. Even that has been at capacity for quite…

> Any sailor would tell you, you don’t go above and below 55 degrees. Elaborate? There are major ports north of 55° and the US, Russia, Canada, Sweden, Norway, Iceland, the UK etc.

North of 55 is ice sheets. South 55 is Cape Horn. Not saying it can’t be done. Just not something you just “do” except for Vikings.

Re: Mexico building rail rival as water shortages drain Panama Canal

#87

Post by jefftk »

reactordev wrote: post #86
jefftk wrote: post #63

Earlier quoted context omitted.

> Any sailor would tell you, you don’t go above and below 55 degrees. Elaborate? There are major ports north of 55° and the US, Russia, Canada, Sweden, Norway, Iceland, the UK etc.

North of 55 is ice sheets. South 55 is Cape Horn. Not saying it can’t be done. Just not something you just “do” except for Vikings.

North of 55 has ice, but isn't all ice sheets. The most extreme example is probably the warm water port of Murmansk at 68° 58'.

Re: Mexico building rail rival as water shortages drain Panama Canal

#88

Post by FpUser »

LargoLasskhyfv wrote: post #60
FpUser wrote: post #48

Earlier quoted context omitted.

This is Krasnoyarsk dam. It is located in small town of Divnogorsk some 40km up the Yenisei river. I was raised in Krasnoyarsk and have seen this with my own eyes.

Thank you! Can you remember how it did sound when in motion?

Nope. I am an old fart living in Canada now and many memories are very rusted ;)

Re: Mexico building rail rival as water shortages drain Panama Canal

#90

Post by RagnarD »

I'm wondering why the whole thing is an issue anyway. Why is there a water shortage? There's an entire ocean on both sides of the canal. Gatun Lake provides the water buffer for the canal. Currently it's freshwater based but it's also artificial to begin with. Why not transition to using salt water pumped from the oceans to top it off as needed? Seems a hell of a lot easier than trying to replace the canals with rails.
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