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Path: utzoo!utcs!lsuc!msb
From: msb@lsuc.UUCP (Mark Brader)
Newsgroups: net.railroad
Subject: Re: Ties
Message-ID: <805@lsuc.UUCP>
Date: Tue, 24-Sep-85 21:39:56 EDT
Article-I.D.: lsuc.805
Posted: Tue Sep 24 21:39:56 1985
Date-Received: Tue, 24-Sep-85 22:25:06 EDT
References: <1608@brl-tgr.ARPA>
Reply-To: msb@lsuc.UUCP (Mark Brader)
Organization: Law Society of Upper Canada, Toronto
Lines: 40
Summary: Concrete ties widespread in UK; old GWR(UK) track described

> 	 The interesting messages about rail technology prompts me to
> 	 ask whether any of you know what has happened to the idea of
> 	 using pre-stressed concrete for RR ties.
> 

British Railways has been using concrete ties* for all new track on fast
lines for years.  I don't know if they still have any wooden ties left.
In a few places they have experimented with a continuous concrete trackbed.

*Called "sleepers" in Britain, of course.

The French TGV line has concrete ties that disappear below the ballast
in the center, giving the appearance of those antique British lines that
had no cross-ties at all, only stone blocks under the rails.

Speaking of antique British lines, I think it might be of interest to
remind people of the original track construction on the Great Western
Railway (of Britain).  This track was 7 feet 1/4 inch in gauge (so that
the wheel flanges were 7 feet apart  exactly).  The load-bearing sleepers
were laid longitudinally, so that the rails were continuously supported.
Cross-ties were placed at intervals of about 10 feet, I think, to maintain
the gauge.  Originally the cross-ties ran continuously across both tracks
(I don't know how they were fastened to the sleepers), and were supported
on vertical piles.  All of this was in wood, of course.  The piles were
removed early on when it was realized that they only impeded resilience,
but the longitudinal-sleeper system survived for many years.  When the GWR
was finally regauged to standard gauge* in 1892, the cross-ties had to be
sawed to the proper length and the rail and longitudinal sleeper moved in.

There is still longitudinal-sleeper track in Paddington Station, London.

*Standard gauge means whatever your 4 feet 8 1/4 inch wheel flanges will
fit.  Traditionally this has been 4 feet 8 1/2 inches, but lines with
stricter tolerance use 4 feet 8 3/8 inches.

Here in Toronto, some of the newer above-ground parts of the subway
system (which, incidentally, is 4 feet 10 7/8 inches gauge) use concrete
ties and Pandrol clips.

Mark Brader