“…The second way to understand the bumpy earth limitation is the von Karman-Gabrielli diagram. This diagram plots the speed and specific power of every mode of transport on a single chart. I love this kind of data presentation.”
[“…acoustic oscillations…ring like a gong or very angry violin”]
How does wear occur? A typical HSR wheel bears a static load of 6 T across a contact patch the size of a postage stamp, with both rail and wheel deforming about 20 microns to enable contact. The center of this patch endures a pressure high enough to plastically deform the rail’s steel! The passage of the wheel places symmetric forces (first forward, then back) but the effect is to temper the surface, which accumulates stresses and can flake off. Additionally, torque on the wheel tends to lock the wheel statically to the track as the patch is loaded, but during the unload portion as the wheel passes the accumulated stresses are released, resulting in shear and friction, particularly on parts of the track where the train is accelerating, slowing down, climbing, or descending.
Despite this terrifying pressure, one wheel passing might deform the surface by only a single Angstrom – the width of a single atom. The Tokaido Shinkansen sees 150 services a day, each with a 16 car train and 4 wheels per track per car, so the track endures 1.5 million wheels between 6-monthly regrindings. Linear damage would imply 0.15 mm of wear, but damage isn’t linear.
Instead, once the rails deform more than a few nanometers, the “bumpiness of the world” comes back with a vengeance. Bumps induce acoustic oscillations in the wheels and track, which ring like a gong or very angry violin. Wheels being made of hard steel, these oscillations are poorly damped…”
A caution about that Karman-Gabrielli diagram in Handmer’s blog. It dates from 1950. In fairness, there is an updated one in Ashton Kemerling’s rebuttal paper here that compares 1950 with 2004 in which HSR is much improved as you would expect to see in a rebuttal paper.
Maglev is probably the best way to go HSR, but again the cost vs what we already have in term of air transport and existing infrastructure and the long distances involved which also drives cost, only China matches USA in this regard and Russian and her affiliated states exceed, probably cancels out its general adoption outside of linking large cities in specific corridors. That’s my neophyte take anyway.
There was never the remotest possibility that it would be built. But look what the illusion has generated in contributions to politicians and you see why it’s still got years to run.
And when it comes down to a choice between this and things the people of California actually need like roads, and that point came perceptibly closer Friday, don’t expect the HSR to go away. It’s the killer AP for generating graft, better even than road building.
I’d like to thank the Democrats of California for making the Big Dig not look so bad in comparison.
I’ll give a Tip of my O’Niell hat to that and give you a hearty 2nd. And so far I’ll note I’ve only visited the Rose Kennedy walking park from underneath.
All of these programs are the same, the more the schedules slip, the worse the budget blows out, the louder the calls to keep going. Otherwise, think of all the money wasted. Think SLS and coming soon, the B-21, fast approaching $1 billion each and sure to go over by some multiple.
In other news, our fearless Fed Chairman barely managed to deny bailing out SVB before another bank failed and it now seems that all those masters of the universe that didn’t realize that $250,000 limit on insured deposits applied to them too, will be protected. Probably the only way to keep a whole string of banks from failing the same way and utterly predictable by anyone paying enough attention to see that 97% of the deposits were uninsured. Good to know the economy is in such perceptive and visionary hands. Oh, it’s the other banks that will pay for this, look for another few years of 0% interest on deposits.
Too big a donor to the Democratic Party to fail.
My take is that:
The government dumped an enormous amount of cash into the economy while production plummeted, while ridiculously claiming that it wouldn’t cause inflation, as if the law of supply and demand had been magically suspended.
When the inflation hit, the Fed started raising interest rates, so the rates banks had to pay on deposits went up.
But the long term government bond yields didn’t go up, as the government was hoping that the inflation and increases in interest rates were just going to slip by, unnoticed. Because if treasure yields go up, it would have a devastating impact on the budget, as the interest payments on the debt would eat up discretionary spending.
But a lot of large lending institutions use government bonds to offset their risk, and SVB had a very high-risk portfolio, packed with green energy and social media tech startups, which weren’t panning out very well, adding a bit of extra stress. And they couldn’t do anything with their pile of long-term government bonds because they hadn’t matured yet, and cashing them in early would’ve broken the bank anyway.
Why they need was for the bonds to be paying interest rates to match the increases the bank was having to pay out, as if US treasury bonds had much higher yields to offset the inflation, and to match the Fed’s hike in interest rates. But that didn’t happen.
So instead we have the mad rush to bail out the bank, which is an ad hoc way of paying the banks the money they would’ve gotten from higher yields on the bonds, and now it looks like the emergency measures will have to be rolled out across the banking sector. So under my notion, the amount the government will have to cough up will about equal the amount that higher-yields on treasury bonds held by large lending institutions would’ve cost. But for treasury bonds held by individuals or overseas, well, you’ll miss out on the emergency fix because you’re not important enough.
If my notion is correct, then it would be an example that elites might think they can cheat the laws of economics, but reality can be pretty harsh about exposing weak points and cheesy hacks, and consequences can be a bitch.
Easy peasy!
Just bring back the Obama Administration’s High Speed Bus Plan described in an excluse Onion video
First Class on the new HSB lines offer ejection seats with built-in parachutes, everyone else gets a handed a complimentary inflatable air bag that can also be used as a seat cushion. Also as part of the new Covid-19 protections all passengers will be required to wear facial masks that fully cover the eyes.
As an additional cost saving measure, it was announced today that Ambus will move to AI controlled autonomous driving software with remote driving when necessary. It is believe removing all drivers system-wide will save the system nearly $1M in annual costs.
…and $300B in insurance liability costs as currently only passengers waive liability as part of their ticket sale.
All those concrete bridges to nowhere, maybe they can mount solar panels or windmills on them?
“Streets of Bakersfield” – Dwight Yoakum & Buck Owens
https://youtu.be/mB7oUI32E1Y
Awesome song! Never seen the video before, thanks!
LOL. If there is grift to be had, they will keep building
FieldRail of Dreams?I *highly* recommend JPL alumnus Casey Handmer’s post on: “Why high speed rail hasn’t caught on” .
https://caseyhandmer.wordpress.com/2022/10/11/why-high-speed-rail-hasnt-caught-on/
“…The second way to understand the bumpy earth limitation is the von Karman-Gabrielli diagram. This diagram plots the speed and specific power of every mode of transport on a single chart. I love this kind of data presentation.”
[“…acoustic oscillations…ring like a gong or very angry violin”]
How does wear occur? A typical HSR wheel bears a static load of 6 T across a contact patch the size of a postage stamp, with both rail and wheel deforming about 20 microns to enable contact. The center of this patch endures a pressure high enough to plastically deform the rail’s steel! The passage of the wheel places symmetric forces (first forward, then back) but the effect is to temper the surface, which accumulates stresses and can flake off. Additionally, torque on the wheel tends to lock the wheel statically to the track as the patch is loaded, but during the unload portion as the wheel passes the accumulated stresses are released, resulting in shear and friction, particularly on parts of the track where the train is accelerating, slowing down, climbing, or descending.
Despite this terrifying pressure, one wheel passing might deform the surface by only a single Angstrom – the width of a single atom. The Tokaido Shinkansen sees 150 services a day, each with a 16 car train and 4 wheels per track per car, so the track endures 1.5 million wheels between 6-monthly regrindings. Linear damage would imply 0.15 mm of wear, but damage isn’t linear.
Instead, once the rails deform more than a few nanometers, the “bumpiness of the world” comes back with a vengeance. Bumps induce acoustic oscillations in the wheels and track, which ring like a gong or very angry violin. Wheels being made of hard steel, these oscillations are poorly damped…”
A caution about that Karman-Gabrielli diagram in Handmer’s blog. It dates from 1950. In fairness, there is an updated one in Ashton Kemerling’s rebuttal paper here that compares 1950 with 2004 in which HSR is much improved as you would expect to see in a rebuttal paper.
Maglev is probably the best way to go HSR, but again the cost vs what we already have in term of air transport and existing infrastructure and the long distances involved which also drives cost, only China matches USA in this regard and Russian and her affiliated states exceed, probably cancels out its general adoption outside of linking large cities in specific corridors. That’s my neophyte take anyway.
There was never the remotest possibility that it would be built. But look what the illusion has generated in contributions to politicians and you see why it’s still got years to run.
And when it comes down to a choice between this and things the people of California actually need like roads, and that point came perceptibly closer Friday, don’t expect the HSR to go away. It’s the killer AP for generating graft, better even than road building.
I’d like to thank the Democrats of California for making the Big Dig not look so bad in comparison.
I’ll give a Tip of my O’Niell hat to that and give you a hearty 2nd. And so far I’ll note I’ve only visited the Rose Kennedy walking park from underneath.
All of these programs are the same, the more the schedules slip, the worse the budget blows out, the louder the calls to keep going. Otherwise, think of all the money wasted. Think SLS and coming soon, the B-21, fast approaching $1 billion each and sure to go over by some multiple.
In other news, our fearless Fed Chairman barely managed to deny bailing out SVB before another bank failed and it now seems that all those masters of the universe that didn’t realize that $250,000 limit on insured deposits applied to them too, will be protected. Probably the only way to keep a whole string of banks from failing the same way and utterly predictable by anyone paying enough attention to see that 97% of the deposits were uninsured. Good to know the economy is in such perceptive and visionary hands. Oh, it’s the other banks that will pay for this, look for another few years of 0% interest on deposits.
Too big a donor to the Democratic Party to fail.
My take is that:
The government dumped an enormous amount of cash into the economy while production plummeted, while ridiculously claiming that it wouldn’t cause inflation, as if the law of supply and demand had been magically suspended.
When the inflation hit, the Fed started raising interest rates, so the rates banks had to pay on deposits went up.
But the long term government bond yields didn’t go up, as the government was hoping that the inflation and increases in interest rates were just going to slip by, unnoticed. Because if treasure yields go up, it would have a devastating impact on the budget, as the interest payments on the debt would eat up discretionary spending.
But a lot of large lending institutions use government bonds to offset their risk, and SVB had a very high-risk portfolio, packed with green energy and social media tech startups, which weren’t panning out very well, adding a bit of extra stress. And they couldn’t do anything with their pile of long-term government bonds because they hadn’t matured yet, and cashing them in early would’ve broken the bank anyway.
Why they need was for the bonds to be paying interest rates to match the increases the bank was having to pay out, as if US treasury bonds had much higher yields to offset the inflation, and to match the Fed’s hike in interest rates. But that didn’t happen.
So instead we have the mad rush to bail out the bank, which is an ad hoc way of paying the banks the money they would’ve gotten from higher yields on the bonds, and now it looks like the emergency measures will have to be rolled out across the banking sector. So under my notion, the amount the government will have to cough up will about equal the amount that higher-yields on treasury bonds held by large lending institutions would’ve cost. But for treasury bonds held by individuals or overseas, well, you’ll miss out on the emergency fix because you’re not important enough.
If my notion is correct, then it would be an example that elites might think they can cheat the laws of economics, but reality can be pretty harsh about exposing weak points and cheesy hacks, and consequences can be a bitch.
Easy peasy!
Just bring back the Obama Administration’s High Speed Bus Plan described in an excluse Onion video
https://www.theonion.com/obama-replaces-costly-high-speed-rail-plan-with-high-sp-1819594916
First Class on the new HSB lines offer ejection seats with built-in parachutes, everyone else gets a handed a complimentary inflatable air bag that can also be used as a seat cushion. Also as part of the new Covid-19 protections all passengers will be required to wear facial masks that fully cover the eyes.
As an additional cost saving measure, it was announced today that Ambus will move to AI controlled autonomous driving software with remote driving when necessary. It is believe removing all drivers system-wide will save the system nearly $1M in annual costs.
…and $300B in insurance liability costs as currently only passengers waive liability as part of their ticket sale.