Hi guys,
Thanks for the replies.
I hadn't realised that the relief lines were added at a later date - thought it had been 4 from the beginning!
I've always thought that one problem with the whole line setup between Reading and Paddington is the ordering of the up and downs (i.e. "up, down, up, down") that cause trains coming in the opposite direction to be slowed or stopped to allow a crossing. Was re-ordering the lines to "down, down, up, up" viable at any stage? or has it been the case that such a big change - moving signals and what to do at a station like Burnham - has meant that it never was (or will be) on the cards.
Cheers,
Boppy.
The four tracking between Paddington and Didcot was quite a complicated progamme completed in the 1880s. The Main complication being that as originally designed Reading and Slough were single sided staions similar to Cambridge today where Down trains were served by the West end and Up trains the East end, crosing in the middle. Later the two broad gauge lines were changed to mixed gauge. The Relief lines were only standard from the start and were mostly built on the North side although it got complicated through Twyford where they were on the South side hence the curved paltforms on the main line. So new platforms were required to serve both the Up main and relief lines at Slough and Reading. It;s also why the RElief line platforms at Langley and Taplow were heavily curved until the platforms were rebuilt. A friend of mine is researching the sequence of the doubling, it's complicated but the net result is that today the 4 lines are paired by use.
We have found out that the current 4 track station of 1884 at Taplow is in fact the second station on the site. A new 2 track (MIXED) station was built on what are now the mainline platforms in around 1872. When the original Maidenhead station on the A4 East of the river bridge was closed When the four tracking the up side buildding was demolised and the current building on platfrom 4 constructed to serve the up Relief.
When the
LSWR▸ and
LNER» 4 tracked out of Waterloo and Liverpool Street the lines are paired by use which makes the termini easier to operate, most suburban services out of Waterloo use platforms 1 -4 whilst at Liverpool Street the Shenfield stopping service use the high numbered platforms. However both built flyovers at Wimbledon and Ilford to give 4 lines paired by direction further out. Also the LSWR/ Sothern built flyovers/unders at most junctions between Waterloo and Woking. Unfortunately the money ran out and Woking remains a bottle neck.
The
ECML▸ is paired by direction but is a mixture of double and 4 track. If you go through Potters Bar Down trains use the new tunnels whilst the Up trains use the original tunnels.
Both the Midland and
WCML▸ are paired by use the Midland originally to Kettering and WCML to Roade and the junction to Northamprton.
It's an interesting operating conumdrum. Pairing by use is probably best for the approach to terminal stations where stopping trains can use platforms to one side and main line trains the other as at Paddington. Whilst pairing by direction is easier to operate out on the main line so you can put fast trains down the middle and switch them to the parrallel line to serve the station and possibly let the following fast past. This was the way one of the last mainlines built in this country the
GWR▸ and
GW▸ /
GC» joint from Old Oak Common to Anyho through High Wycombe was designed. Whilst mainly double track there were 11 places where fast trains could overtake stoppers. There were also flying junctions where the independant GC and GW lines branched. In fact you still go over the flyover at Ashendon on an Up train to Marylebone although the junctions long since gone. It's some of those loops Chiltern wants to put back.
If there were ever to a flyover at Woking then the LSWR mainline from Waterloo to Worting Junction could probably count as the almost perfect mixed use railway.