Not a good time to shake
May 23, 2022 8:49 AM Subscribe
Do high-speed train engineering designs account for earthquakes in seismic event-prone regions?
I was recently on an Amtrak train in northern San Diego County that was going pretty fast. Judging by the relative speed of adjacent freeway traffic, I would guess the train was going around 90 MPH. And that got me thinking...what would happen to the train (and me!) if there were an earthquake?
In Japan and China, both of which are prone to earthquakes, the question seems even more germane since they are also both earthquake-prone places and they have a lot more high-speed rail, and their train speeds are significantly higher than in the US.
Do train engineers design in any safety features that help prevent catastrophic high-speed derailments in the event of an earthquake?
I was recently on an Amtrak train in northern San Diego County that was going pretty fast. Judging by the relative speed of adjacent freeway traffic, I would guess the train was going around 90 MPH. And that got me thinking...what would happen to the train (and me!) if there were an earthquake?
In Japan and China, both of which are prone to earthquakes, the question seems even more germane since they are also both earthquake-prone places and they have a lot more high-speed rail, and their train speeds are significantly higher than in the US.
Do train engineers design in any safety features that help prevent catastrophic high-speed derailments in the event of an earthquake?
In the US, trains and many other systems are integrating with the USGS shakealert system. Here is one example from southern CA.
posted by rockindata at 9:54 AM on May 23, 2022 [1 favorite]
posted by rockindata at 9:54 AM on May 23, 2022 [1 favorite]
Poland doesn't have earthquakes, but does have long-lived mines that can cause similar damage. Here's a very impressive damaged narrow-gauge line - and it got fixed within two weeks. This one made the line impassable, but smaller misalignments just force trains to slow down a lot.
(Also 90 mph isn't fast at all for a passenger train. EU norms say 100 for all main passenger lines, and the minimum for high speed-ish is 125.)
posted by I claim sanctuary at 10:03 AM on May 23, 2022
(Also 90 mph isn't fast at all for a passenger train. EU norms say 100 for all main passenger lines, and the minimum for high speed-ish is 125.)
posted by I claim sanctuary at 10:03 AM on May 23, 2022
Of course they do.
Here's a really basic primer:
PDF
It shows earthquake maps of the US, determines what zones require what type of seismic protection, and give some really basic construction design considerations.
Retrofit factors include the following design considerations:
Seismic Design for Railway Structures
© 2018, American Railway Engineering and Maintenance-of-Way Association
9-1-50 AREMA Manual for Railway Engineering
(1) Changing characteristic resonant frequencies and/or amplitudes (damping) of response to reduce seismic forces in
the structure.
(2) Strengthening components of the structure to accommodate the seismic loads.
(3) Providing alternate paths for seismic forces within the structure.
(4) Accommodating displacements with catchers, stoppers, enlarged bearing areas or other devices (see Paragraph c
below).
(5) Providing for "yielding type response" (such as "plastic" hinges) at non-critical points of the structure to relieve
seismic stresses.
posted by The_Vegetables at 12:15 PM on May 23, 2022 [2 favorites]
Here's a really basic primer:
It shows earthquake maps of the US, determines what zones require what type of seismic protection, and give some really basic construction design considerations.
Retrofit factors include the following design considerations:
Seismic Design for Railway Structures
© 2018, American Railway Engineering and Maintenance-of-Way Association
9-1-50 AREMA Manual for Railway Engineering
(1) Changing characteristic resonant frequencies and/or amplitudes (damping) of response to reduce seismic forces in
the structure.
(2) Strengthening components of the structure to accommodate the seismic loads.
(3) Providing alternate paths for seismic forces within the structure.
(4) Accommodating displacements with catchers, stoppers, enlarged bearing areas or other devices (see Paragraph c
below).
(5) Providing for "yielding type response" (such as "plastic" hinges) at non-critical points of the structure to relieve
seismic stresses.
posted by The_Vegetables at 12:15 PM on May 23, 2022 [2 favorites]
In Japan, the trains automatically stop as soon as the p-waves from an earthquake have been detected in the vicinity, which can be a pretty jarring experience!
I was taking the Tsukuba Express (a very fast regional line) one day in April 2011 when an after-shock from the Tohoku Earthquake happened. The train slammed the brakes on and stopped before the 6.1 magnitude quake arrived. The conductor made an announcement that we were about to be hit by an Earthquake and to be prepared, and then apologized profusely for the inconvenience of the delay. After the train stopped rocking, we waited a few minutes while the tracks were inspected for damage before we proceeded on like nothing happened. For what it is worth, this was just an everyday experience...
The recent 7.4 quake caused a Shinkansen to derail, since it was too close to the epicenter and couldn't stop in time. Here is a good article also talking about the lessons learned from a couple of recent occasions, as well as outlining some of the systems that are in place and how effective they've been overall. (It isn't behind a paywall unlike the Japan Times article.) It takes a lot for damage to happen to the support structure, and as over-engineered as they appear, there has been a lot of work to upgrade them.
The thought of being on an American train during an earthquake is pretty horrifying, we are so backwards technologically and our building standards and infrastructure are horrible compared to Japan or China...
posted by rambling wanderlust at 12:42 PM on May 24, 2022 [1 favorite]
I was taking the Tsukuba Express (a very fast regional line) one day in April 2011 when an after-shock from the Tohoku Earthquake happened. The train slammed the brakes on and stopped before the 6.1 magnitude quake arrived. The conductor made an announcement that we were about to be hit by an Earthquake and to be prepared, and then apologized profusely for the inconvenience of the delay. After the train stopped rocking, we waited a few minutes while the tracks were inspected for damage before we proceeded on like nothing happened. For what it is worth, this was just an everyday experience...
The recent 7.4 quake caused a Shinkansen to derail, since it was too close to the epicenter and couldn't stop in time. Here is a good article also talking about the lessons learned from a couple of recent occasions, as well as outlining some of the systems that are in place and how effective they've been overall. (It isn't behind a paywall unlike the Japan Times article.) It takes a lot for damage to happen to the support structure, and as over-engineered as they appear, there has been a lot of work to upgrade them.
The thought of being on an American train during an earthquake is pretty horrifying, we are so backwards technologically and our building standards and infrastructure are horrible compared to Japan or China...
posted by rambling wanderlust at 12:42 PM on May 24, 2022 [1 favorite]
California thinks about this kind of stuff all the time. Seismic considerations, research and requirements are a part of every project. There are enormous amounts of completely dorky and dry information on this subject, from early warning systems for rail transit to engineering and design specifications.
From the California High Speed Rail plan 2011:
• TheCHSTP design earthquakes and performance objectives are based upon:
o Similar criteria in Taiwan and Japan for the lower level Operating Basis Earthquake
o Current California Department of Transportation (Caltrans) criteria for the higher level Maximum Considered Earthquake
posted by oneirodynia at 2:21 PM on May 24, 2022
From the California High Speed Rail plan 2011:
• TheCHSTP design earthquakes and performance objectives are based upon:
o Similar criteria in Taiwan and Japan for the lower level Operating Basis Earthquake
o Current California Department of Transportation (Caltrans) criteria for the higher level Maximum Considered Earthquake
posted by oneirodynia at 2:21 PM on May 24, 2022
This thread is closed to new comments.
https://www.japantimes.co.jp/news/2022/03/18/national/tohoku-train-derailment-shinkansen/
posted by sebastienbailard at 9:06 AM on May 23, 2022 [3 favorites]