Sunday, October 31, 2010

RE: China's high speed rail

Thanks Andrew,

I guess it's a matter of focus. I focused on the 10,000 miles of track.

Rightly or wrongly I assumed the technology was little different than that
of the APT, TGV and bullet trains. And as with all this technology none of
it is operated at the world record speeds they set. And therefore the speed
record is of little significance, they've simply joined the club.

As such the tracks therefore are usuable by conventional trains, there are
just a few minor differences in track characteristics, like long straight
lines.

And I assume the plains of China are relatively flat, so there would be few
bridges required. So main structural type issues are:

1) Continuously welded track
2) Timber sleepers, reinforced concrete sleepers, or new polymer based
sleepers.
3) Signage and signals
4) Station buildings and platforms

Though they could opt for a high speed bus service like Adelaide's O'Bahn:
the buses move between road and high speed tracks. The precast concrete
tracks can be assembled on site with less site preparation then conventional
rail. But the buses don't travel any where near as fast as trains. The
intermodal system does however collect people from the local neighbourhoods
and move them to the high speed track: for most routes with out the need to
change bus. The 1 hour conventional trip being reduced to 20 minutes on the
O'Bahn. It takes an hour by car as well, so O'Bahn gives more freedom to
spend time doing what want to do, than wasting time travelling.

Due to the way the track is constructed there is less need for cut and
build-up of the site, basically an elevated open framework, so siteand track
drainage is also less of a problem.

Moving from agrarian society to industrialised typically requires that less
than 10% of population is involved in agriculture, and majority involved in
manufacturing and construction type work. So building the railway tracks
will provide work away from farming.

There can be side effects to. In replacing the timber sleepers with concrete
sleepers on the Adelaide to Perth track, there became a large supply of
timber sleepers available for garden retaining walls: businesses sprang up
building such walls and supplying the sleepers. The timber sleepers are now
rare, and concrete sleeper retaining walls are now more common. So if some
of the high speed track being constructed in China is upgrade of existing,
then there will be resources available for alternatives use. Dyanamic
adaptive systems: no telling where they will go.

Generally I have little interest in sport, a waste of resources when people
are starving. On the otherhand it provides employment, so what is and is not
a sensible activity to pursue is difficult to say. Moving away from
producing food to relying on others to produce food is a major risk to take.
And whether have capitalism or communism: both are dynamic adaptive systems
with markets: they just operate differently: one has many centres of control
and the other a supposedly single centre. And no nation on earth has an
economy which is purely one form or the other. Better to discuss the
dynamics of the supply system, than argue the emotive terms of capitalism
versus communism: neither approach is much use. Its about time something new
was said in economics.

In short I didn't see any posturing.

Also many structural/mechanical issues involved with trains and associated
infrastructure. And I assume the list is not just limited to structures of
buildings. Is the body of the vehicles an integral shell, or a frame and
fabric system? I'm sure many structural questions could be asked if got away
from the politics.

Regards
Conrad Harrison
B.Tech (mfg & mech), MIIE, gradTIEAust
mailto:sch.tectonic@bigpond.com
Adelaide
South Australia


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