confliction【英文文献及翻译】中国高速铁路China High-Speed Railway

2021年1月23日发(作者：haunt)
兰州交通大学毕业设计（论文）

China High-Speed Railway
As the economic grow, intercity travel demand has increased dramatically in the Greater
China Area. Traditional railways can hardly satisfy the passenger and freight travel demand,
high speed rail is
hence proposed and constructed
after 1990s.
This
study
aims to
integrate
current development of both rail-based and Maglev high speed trains in this area. From 1997,
Taiwan kicked-off its
high speed rail construction by importing the technology of Japanese
Shinkansen. The Taiwan High Speed Rail is a 15-billion US dollars project. To save the cost
of construction and management, the BOT model was applied. Though not totally satisfied,
this
project
is
still
successful
and
ready
to
operate
in
the
4th
quarter
of
2007.
China
is
preparing
its
high
speed
rail
services
by
upgrading
current
networks.
The
capacity
and
operating
speed
are
all
increased
after
5-times
system
upgrade.
The
6th
upgrade
will
be
initiated in 2006. By then, trains will run at a speed of 200km/h in a total distance of 1,400km
in 7 different routes. From the white paper published by the Ministry of Railway in China,
there
will
be
totally
8
rail-based
High
Speed
Train
services.
Four
of
them
are
North-South
bound, and four of them are East-West
bound. 5 of the 8
High Speed Rails are now under
construction, the first line will be finished in 2009, and the 2nd one will be in 2010. By 2020,
there will be totally 12,000 kilometers high speed rail services in China. The 250 billion US
dollars
construction
cost
still
leaves
some
uncertainties
for
all
these
projects.
Finally,
the
future
of
the
Maglev
system
in
China
is
not
so
bright
as
rail-based.
Shanghai
airport
line
could be the first, also the last Maglev project in China if the approved Shanghai-Hangzhou
line cannot raise enough 4.4 billion dollars to build it.
Steel rail composition






Steel rail is composed of iron, carbon, manganese, and silicon, and contains impurities
such as phosphorous, sulphur, gases, and slag. The proportions
of these
substances may be
altered to achieve different properties, such as increased resistance to wear on curves.





The
standard
configuration
for
North
American
rail
resembles
an
upside
down
T.
The
three parts of T-rail are called the base, web, and head. The flat base enabled such rail to be
spiked directly to wooden crossties; later, rail was placed on the now-standard steel tie plate.
While the proportions and precise shape of rail are subject to constant analysis and refinement,
the basic T-section has been standard since the mid-19th century.

Weight



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兰州交通大学毕业设计（论文）





The most common way of describing rail is in terms of its weight per linear
yard (the
historic British unit of length), which is a function of its cross section. In the late 19th century,
rail was produced in a range of sections weighing between 40 and 80 lbs. per yard. Weights
increased
over
time,
so
that
rail
rolled
today
weighs
between
112
and
145
lbs.
(The
Pennsylvania Railroad's 155-lb. section, used for a time after World War II, was the heaviest
used in the U.S.)



Jointed rail segments






The length of standard rails has historically been related to the length of the cars used to
transport them. From an early range of 15-20 feet, rail length increased with car size until a
standard
of
39
feet
(easily
accommodated
by
the
once-common
40-foot
car)
was
reached.
Even with the advent of today's longer cars, 39 feet has remained the standard for rail owing
to limitations in steel mills and ease of handling.





The joints in rail
—
its weakest points
—
can make for a rough ride, and are expensive to
maintain. Individual rails are joined with steel pieces called joint (or angle) bars, which are
held
in
place
by
four
or
six
bolts.
Today,
the
six-bolt
type,
once
reserved
for
heavy- duty
applications, is standard. The bolts in a joint bar are faced alternately outward and inward to
guard
against
the
remote
possibility
that
a
derailed
car's
wheel
would
shear
them
all
off,
causing the rails
to
part. Transition
between rails
of two different
weights
is
achieved with
special angle bars.
In territory where the rails serve as conductors for signal
systems,
bond
wires must be used at the joints to maintain the circuit.

Welded rail






The troublesome nature of rail joints prompted the most easily recognized advance in rail
technology: the adoption of continuous welded rail (CWR).
From its early use on a handful of roads in the 1940's, welded rail has come to be preferred for
almost
all
applications.
It
is
produced
by
welding
standard
39-foot
(or
newer
78-foot)
segments together into quarter-mile lengths at dedicated plants.





The
rails
are
transported
to
where
they're
needed
in
special
trains,
which
are
pulled
slowly
out
from
under
the
rail
when
it
is
to
be
unloaded.
When
in
place,
CWR
is
often
field-welded
into
even
greater
lengths.
Much
jointed
track
survives
because
of
the
long
lifespan
of
even
moderately
used
rail,
and
because
the
specialized
equipment
needed
for
CWR installation is not economical for short distances.


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兰州交通大学毕业设计（论文）





Managing
the
expansion
and
contraction
that
comes
with
temperature
change
is
important with CWR. To avoid expanding and potential buckling when in service, welded rail
is laid when temperatures are high (or is artificially heated). Rail anchors clipped on at the ties
keep the rail from getting shorter as it contracts with falling temperatures. Thus constrained, it
shrinks in cross section (height and width), but not in length. Because it's in tension, welded
rail is treated with care during trackwork in cold weather.

Maintaining and reusing rail






Under heavy traffic, rails get worn down, although their life can be extended by grinding
the head back to the proper contour.

Rail no longer suited for main-line use may still have some light-duty life in it and is often
relaid on branches, spurs, or in yards. Main-track reduction projects are also sources of such






When rail wear is uneven at a given location (such as a curve), rail may be transposed
from one side to another to get maximum use out of it.


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