On Wed, 28 Dec 2005, Roland Perry wrote:

In message , at 14:26:02 on Wed, 28 Dec 2005,
Paul Terry remarked:
In message , Roland Perry
writes

Why can't the railway be put in a shallow concrete sided cutting?

And there wouldn't be room to sink the line between Barnes junction and
the first crossing at Rocks Lane - in fact it would be difficult to get
low enough before the second crossing at White Hart Lane.

A bit over 0.6 mile. The ramp down from Blackfriars to City Thameslink is
about a third of that distance.

0.6 miles = 960 m; at a grade of 1:30, which i think is the steepest you
can sensibly have, that's enough to drop 32 metres. That seems more than
enough! IANAEngineer, but if we want a W8 gauge route, we need 3.6 m
clearance above the rail; allowing 1.4 m from the top of the 'railspace'
to the deck of the road, that's 5 metres that needs to be dropped, for a
slope of 1:192, which really doesn't seem a lot.


tom

--
Judge Dredd. Found dead. Face down in Snoopy's bed.