Bullet-train planners face huge engineering challenge

[XemaSab]

The plan calls for bullet trains to shoot east from Bakersfield at 220 mph, climbing one of the steepest sustained high-speed rail inclines in the world. It would soar over canyons on viaducts as high as a 33-story skyscraper. The line would duck in and out of tunnels up to 500 feet below the rugged surface. It would cross more than half a dozen earthquake faults heading toward L.A.

Tunneling machines as long as a football field will have to be jockeyed into mountain canyons to do the heavy, back-breaking work once left to Chinese laborers. New access roads and a corridor for high-voltage power lines will have to be carved through the Tehachapis to feed power-hungry trains. When completed and fully operational, the bullet train will need an estimated 2.7 million kilowatt hours of electricity each day — about a quarter of Hoover Dam's average daily output.

(snip)

One measure of the topographic challenge: Over that 141 miles from Bakersfield to Los Angeles, up to 59% of the track would run in tunnels or on viaducts, according to preliminary planning documents.

(snip)

There are half a dozen faults between Bakersfield and Los Angeles, including the White Wolf and San Andreas, both capable of producing a 7.5 magnitude quake. Where high viaducts are near faults, engineers are considering reinforced concrete structures that would resist ground motion and have containment features to prevent a derailed bullet train from plunging to the ground, Gillam said.

http://www.latimes.com/news/local/la-me-bullet-mountains-20121113,0,4082877.story

[Chunk]

1. Does Japan have earthquakes?

[happyslug]

2. But NO 220 mph trains

When first built in the 1960, top speed was 140 mph, top speed is now 190, but only on some trains and then only for shirt distances. Most trains operate at 150 mph.

http://en.wikipedia.org/wiki/Shinkansen

Top speed on the Chunnel is 186 mph:
http://en.wikipedia.org/wiki/High_Speed_1

The French TGV has done 357.2 mph, but under test conditions only:
http://en.wikipedia.org/wiki/TGV

The TGV was in 2007 the world's fastest conventional scheduled train: one journey's average start-to-stop speed from Lorraine-TGV to Champagne-Ardenne-TGV is 279.3 km/h (173.5 mph). This record was surpassed on December 26, 2009 by the newly opened Wuhan-Guangzhou High-Speed Railway in China where the fastest scheduled train covered 922 km (573 mi) at an average speed of 312.54 km/h (194.20 mph). However, on July 1, 2011 in order to save energy and reduce operating costs the maximum speed of Chinese high-speed trains was reduced to 300 km/h, and the average speed of the fastest trains on the Wuhan-Guangzhou High-Speed Railway was reduced to 272.68 km/h (169 mph), slower than the TGV.

One of the problems with speed, as you go faster, cost escalates, Noise Escalates AND the ability of the wheels to propel themselves on the rail goes down.

Thus, most studies have recommend 120-180 mph trains, if you go any faster the cost of going that fast gets excessive, as the Chinese found out.

The general rule of thumb is if you are looking at going faster then 200 mph, Mag-lev is the way to go. The problem with Mag-lev is you can NOT use existing lines in cities to provide service to those cities. The TGV, for example, uses a lot of local railroad lines to get to the rail stations in the cities of France. Japan's high speed trains do NOT do the same, for Japan's railroad system, before the adoption of the high speed train in the 1960s, was narrow gage not standard gage and Japan made a commitment to Standard gage for its high speed rail (and thus had to build new stations for the high speed trains with new lines right through their major cities).

Remember the main restrictions on train speed is NOT the wheels or the rails, but the road bed. The road bed has to be designed to take the stress of high speed trains, and have very gradual curves so the train does not have to slow down for any curve. In France, the attitude was if the High Speed Train was getting close to a city, it will have to slow down anyway to stop, thus low speed rails use in such location are not a problem. The TGV speed is from the fact between the major cities it is on its own right of way, independent of slower trains and with no cross traffic.

Please note, Amtrak Acela can do 150 mph, through it averages half that speed but that is due to the fact that the rail line it operates on is NOT designed for trains going 150 mph.
http://en.wikipedia.org/wiki/Acela_Express

Another factor is the Federal Railroad Administration (FRA) continuation of a 1912 law (the law itself has been repealed, but the regulations that reflect that law is still in place) that require all passenger rail cars to withstand impacts of up to 1 Million foot pounds of force. This requires a heavy steel superstructure that increase operating costs AND the tendency for the Rail Car to roll (i.e. it means rail cars must be so heavy you could hit it with a tank, and it would survive intact).

More on the Regulations
http://www.ebbc.org/rail/fra.html
http://pedestrianobservations.wordpress.com/2011/10/17/fra-stonewalling/
http://systemicfailure.wordpress.com/2010/01/09/fra-sabotages-passenger-rail-again/
http://zierke.com/shasta_route/intro-2005-04-07.html


The Actual FRA Regulations being discussed above:
http://www.fra.dot.gov/downloads/research/uscr_std.pdf
http://www.fra.dot.gov/rrs/downloads/safety/Compliance%20Manuals/Chapter12_2012.pdf

[hunter]

3. Part of me says "Cool!" Another part asks why we are in such a hurry.

What would the world look like if nothing moved faster than, say, a leisurely 35mph?

I think a slower paced, less economically "productive," less environmentally destructive, human civilization would be a much nicer place.