When grade-separating quad tracks paired by direction, is it ever considered to slew the outer tracks and insert the turnouts in-between? Example an alternate Hitchin could be: DS-turnout-DF // UF-turnout-US, instead of turnout-DS-DF // UF-US-turnout.
That would remove the need for a DF train to cross the DS in order to access the diverging route, and require not much more land take than for an 'outer' turnout. Also, since the slewed outer tracks are likely to be the Slows, it probably wouldn't cause much compromise on linespeeds.
Isn't that how Airport Junction looks (between Hayes and Heathrow)? It's also, I think, the plan for grade separating Werrington Junction (if ever that plan comes to fruition), largely because there's already a handy gap between the Down Fast and the Up Stamford.
Correct me if I'm wrong.
Isn't that how Airport Junction looks (between Hayes and Heathrow)?
Isn't that how Airport Junction looks (between Hayes and Heathrow)? It's also, I think, the plan for grade separating Werrington Junction (if ever that plan comes to fruition), largely because there's already a handy gap between the Down Fast and the Up Stamford.
Correct me if I'm wrong.
GW is paired by use, not paired by direction. Following the rebuild, both mains and reliefs have grade separation. From the perspective of the through lines, all the branch connections are on the outside.
An interesting feature of the final layout (Xmas 2016 in the article linked in the above post) is that they will still have some alternative routes as well, e.g. using the crossovers on the branch there are two routes shown from branch to up main, and two routes from down relief to branch, I'm assuming the two airport flyovers are bi-directional.
The consultation leaflet somebody linked to on another thread
The double grade separation at Hampton Court Junction is impressive and in fact it can be easy to forget about the line to/from Oxshott given the flyover taking the Down Hampton Court branch. This is an old diagram that appears to show the Down Hampton Court branch as being a dive-under.
Network Rail Infrastructure Limited (Network Rail) of 1 Eversholt Street, London, NW1 2DN, has applied to the Secretary of State for Transport under section 6 of the Transport and Works Act 1992, for the above-mentioned Order under sections 1 and 5 of that Act.
The draft Order gives statutory authority to Network Rail for the construction, maintenance and operation of a grade separated junction in the form of a dive under beneath the East Coast Main Line (ECML) at Werrington junction. This will remove a key rail bottleneck in the Peterborough area, allowing trains from the Stamford Lines to reach the Great Northern Great Eastern lines without crossing the East Coast Main Line on the level. The scheme will, in combination with other schemes, increase the capacity on the ECML to allow for up to two extra train paths per hour in each direction for long distance high speed trains.
The construction of the new dive under requires works to move the Stamford lines westwards to allow space for the tracks to pass beneath the ECML. The scheduled works include a replacement footbridge at Cock Lane; diversion of Brook Drain and related watercourses; a widened Lincoln Road bridge, a further bridge to carry utility apparatus and a footpath, bridleway and cycle-track over the railway and a new access road for properties on Hurn Road. Temporary bridges over the Marholm Brook and the railway will allow access during construction to the main construction compounds. The Order also authorises further ancillary works including utilities diversions.