Re: Sleepers at Diamond Crossings

[jim@sprockets.co.uk (Jim Guthrie)]

On Fri, 23 Apr 1999 05:41:41 GMT, jdennis@acslink.net.au (John Dennis)
wrote:

John

>I am wondering whether anybody knows what the "proper" arrangement of
>sleepers is at a diamond crossing approaching a right angle.  I am not
>looking for a flat crossing on a main line, rather for one siding
>crossing another.  Low speed stuff.

I've just had a look at some photographs of a couple of main line
right angle crossings taken when they were under construction in the
UK and the crossings were supported on a lattice of very heavy beams -
possibly wood in one case and steel in the other.    The beams were
positioned under each rail and stretched across the complete crossing
between the ends of the outermost check rails.

The FB rails were fitted directly to the beams - with spikes on the
wooden beams and bolted down clamps on the steel beams.   There were
no intermediate sleepers - i.e. there were square or rectangular
"holes" in the four foot and six foot ways between the beams,
presumably to be filled with ballast when the work was complete.

The installations were for main line usage hence,  I presume,  the
massive construction.

For your siding,  I would reckon that such a construction would be
excessive,  and I wondered if you could get away with an easier form
of construction whereby the sleepering on one line was run through the
crossing,  but with two of the sleepers at about 4'6" pitch (for
standard gauge) and being of heavier and wider cross section across
which the other line ran - these sleepers being wide enough to take
the rail fixings for the running and check rails of the secondary
line.    I've done a quick sketch of what I thought and dumped it as a
.GIF on my web site at www.netcomuk.co.uk/~sprocket/crossing.gif so
that I don't get flamed for posting attachments :-).  The gauging of
the secondary line through the crossing could be maintained by a
fairly hefty checkrail/running rail "diamond" and the primary line
could be supported in the diamond by an intermediate sleeper.

Or you could take the easy way out and pave your crossing area so that
only the tops of your rails were showing :-).

Jim. 
S7 Dabbling at www.netcomuk.co.uk/~sprocket/index.html