"Tom Anderson" wrote in message
th.li...
SNIP
BRAINWAVE.

On this group, we have two long-standing conundra: how to run the circle
line efficiently, and what to do with the recently disused Widened Lines.

Each is, of course, the solution to the other. We have the exclusive use
of the Widened Lines between Farringdon junction and Moorgate. On that
stretch, there are platforms at Barbican. We build two new bits of track,
and a bunch of crossovers:

- a trailing link from the inner Circle to the up Widened as far west as
possible; east of Farringdon, west of Barbican - this would be a trivial
extension of the Cowcross Street sidings

- a facing crossover from the up to the down Widened immediately east of
the above

- a facing crossover from the outer to the inner Circle also immediately
east of the link

- a facing link from the up Widened to the inner Circle west of Moorgate -
probably involving the Met sidings at Moorgate, at their western end

- a trailing crossover from the up Widened to the inner Circle west of the
link, which probably means west of the existing facing crossover (which is
west of the existing trailing crossover)

- a trailing crossover from the down to the up Widened west of the link

You then redesignate (fast/slow is arbitrary here):

- outer Circle - outer Circle fast
- inner Circle - outer Circle slow
- up Widened - inner Circle slow
- down Widened - outer Circle fast

And you have a four-track Circle between Farringdon and Moorgate, with no
flat crossings. Essentially, Barbican looks just like Edgware Road. You
can have trains on the slows sit in the platforms for as long as they need

Currently looks like this (|- denotes the severed tracks at Farringdon):

Barbican Moorgate

### ###
------------------------------+---------+---------
\ /
--+-----------------------------+---+-+-----------
\ ### \ ####
CX St ------+-+-------#
sgds \ #
+-----#
### ####
|------------------------------------------------#
#
|------------------------------------------------#
### ####

And would become (tracks not in routine use dashed):

### ###
---+---------------------+---+---------+---------
\ / \ /
---+-+-----------------+- - - -+-+-+-+-----------
\ ### / \ ####
\ +- - -+-+- - - -#
\ / \ #
\ / +- - -#
\ ### / ####
|- - - - -+-+-------------+-+- - - - - - - - - -#
\ / #
|- - - - - - -+---------+- - - - - - - - - - - -#
### ####

The stubs of Widened line at the Farringdon end probably wouldn't be long
enough to be of any use, but the stubs at the Moorgate end would all be
usable in one way or another. You might need a few more links or
crossovers to make full use of them. Whatever you do, they'll involve flat
crossings, though.

Actually, a cheaper version of this plan would just be to rearrange the
Cowcross Street sidings as a short four-track stretch. I'm not sure it's
long enough, but if it is, that would be somewhere to hold trains which
needed holding.

tom

--
Argumentative and pedantic, oh, yes. Although it's properly called
"correct" -- Huge

A study of Underground history will show a similar situation at Gloucester
Rd and South Kensington dating from the days of District vs Met egos. You
have side platforms @ Barbican. Unless extensively rebuilt as well, you
won't have the outer rail splitting to sharing sides of one island, inner
rail the other. Instead, the outer rail will be split to one side platform
and one side of the central island. If the down widened lines platform space
is still there, the same would appy to the inner rail. So, there'll be a
load of hoofing it up/down stairs involved. Bifurcation is a good idea, but
only with ISLAND platforms.

Cheers

David down under