London Banter - View Single Post

Roland Perry · April 25th 17, 07:19 AM posted to uk.transport.london

In message , at 15:52:14
on Mon, 24 Apr 2017, remarked:

You could say the same of the busway of course, and probably have. The
Borders Railway is an awful lot longer though.

Maybe didn't have things as difficult as the Ouse viaduct and the
Trumpington cutting to deal with.

They certainly did. A tunnel needed major works and the Hardengreen
viaduct is longer than the Ouse one UIVMM.

The Ouse viaduct is 220m (Guided bus leaflet Jan 2009), and the
Hardengreen one approximately three sprinter carriages (from photos,
so about 75m).

The total Hardengreen structure is longer than that. More like 100m and
looks longer than the Ouse viaduct.

It's an embankment on dry land, not a bridge over a river and flood
plain. The part which spans the road is just two short sections of
concrete beam with a central pillar.

I suspect the Ouse Viaduct would have been cheaper to restore for a
railway.

Why? Because of the greater load imposed by a train compared to a bus?

The bus structure is quite a bit wider I suspect and I doubt that the 220m
is all viaduct.

The bus structure has the advantage of being slightly arched, and a
third of the width is the cycle track. From a structural point of view
the dominant parameters are the length of the unsupported span, and the
design load.

Looking at Bing Maps, I think that the 220m is all viaduct (rather than
try to establish sections of embankment close to the river) but with
numerous supporting pillars at 30m intervals. [Making seven sections =
220m, versus two sections at Hardengreen]
--
Roland Perry