Northern Sydney Freight Corridor (NSFC)

 
  Transtopic Assistant Commissioner

I've already mentioned this earlier in this thread, but the piers for the "new" John Whitton Bridge were originally built to accommodate 4 tracks.  Only the spans for 2 tracks on the eastern side of the piers were built initially to replace the existing 2 tracks on the "old" Meadowbank Bridge, leaving room for the additional spans on the "new" bridge to complete quadruplication.  When the quadruplication is completed, the tracks across the bridge will have to be reconfigured to match the 2 Up and 2 Down parallel alignments.

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  Piston Train Controller

I've already mentioned this earlier in this thread, but the piers for the "new" John Whitton Bridge were originally built to accommodate 4 tracks.  Only the spans for 2 tracks on the eastern side of the piers were built initially to replace the existing 2 tracks on the "old" Meadowbank Bridge, leaving room for the additional spans on the "new" bridge to complete quadruplication.  When the quadruplication is completed, the tracks across the bridge will have to be reconfigured to match the 2 Up and 2 Down parallel alignments.
Transtopic
I have been reliably told by two of the engineers who were involved with the construction of the new bridge that standards have changed and it is not a simple issue of just dropping in additional girders for the extra tracks.
Also the Chullora Workshops where the original beams were constructed are no longer capable of producing more beams and all tooling and jigs are no longer around.
  UpperQuad Station Master

Location: 184.8 miles to Sydney
I have been reliably told by two of the engineers who were involved with the construction of the new bridge that standards have changed and it is not a simple issue of just dropping in additional girders for the extra tracks.
Also the Chullora Workshops where the original beams were constructed are no longer capable of producing more beams and all tooling and jigs are no longer around.
Piston
So it won’t be a simple job, new girders can’t be built in-house, and they must conform to new standards. Hardly show-stoppers.
  M636C Minister for Railways

I've already mentioned this earlier in this thread, but the piers for the "new" John Whitton Bridge were originally built to accommodate 4 tracks.  Only the spans for 2 tracks on the eastern side of the piers were built initially to replace the existing 2 tracks on the "old" Meadowbank Bridge, leaving room for the additional spans on the "new" bridge to complete quadruplication.  When the quadruplication is completed, the tracks across the bridge will have to be reconfigured to match the 2 Up and 2 Down parallel alignments.
Transtopic
The piers were built (or at least one complete pier, a number of incomplete piers and both abutments) were built in the late 1940s or early 1950s. My recollection is that the piers were in the same style as those of the second Hawkesbury bridge. I believe that the piers were intended to carry double track through steel girders similar to those of the Hawkesbury bridge.

When the existing bridge was in need of replacement, the existing piers were modified to take four box girder beams supporting the tracks. To fit four tracks on the existing piers meant that the clearances had to be reduced below the normal standard. Only two tracks were installed.

There should be no problem in getting additional beams to the existing or to a modified design. However it is not possible to increase the clearances between the tracks. Since the bridge is straight this isn't that serious.

Peter
  The Inevitable Looney Beginner

I've already mentioned this earlier in this thread, but the piers for the "new" John Whitton Bridge were originally built to accommodate 4 tracks.  Only the spans for 2 tracks on the eastern side of the piers were built initially to replace the existing 2 tracks on the "old" Meadowbank Bridge, leaving room for the additional spans on the "new" bridge to complete quadruplication.  When the quadruplication is completed, the tracks across the bridge will have to be reconfigured to match the 2 Up and 2 Down parallel alignments.
The piers were built (or at least one complete pier, a number of incomplete piers and both abutments) were built in the late 1940s or early 1950s. My recollection is that the piers were in the same style as those of the second Hawkesbury bridge. I believe that the piers were intended to carry double track through steel girders similar to those of the Hawkesbury bridge.

When the existing bridge was in need of replacement, the existing piers were modified to take four box girder beams supporting the tracks. To fit four tracks on the existing piers meant that the clearances had to be reduced below the normal standard. Only two tracks were installed.

There should be no problem in getting additional beams to the existing or to a modified design. However it is not possible to increase the clearances between the tracks. Since the bridge is straight this isn't that serious.

Peter
M636C
Peter, Is the clearance between the existing 2 tracks is also reduced? If so, then clearly not a problem.
  M636C Minister for Railways

Peter,
Is the clearance between the existing 2 tracks is also reduced? If so, then clearly not a problem.

Yes

The reduced clearances apply on the two existing tracks on the bridge.
This is not a problem in general for passenger trains, since the widest suburban trains can now run with no problems.

However for freight trains allowances are provided for wider than standard loads and for loads only slightly out of gauge in "standard" clearances. Special arrangements would be needed for running such loads at Meadowbank.

I suspect that "standard" clearances have been further increased since the Meadowbank bridge was completed and the reduced clearances might be regarded as more significant.

Peter
  simstrain Chief Commissioner

I don't agree sims.  There is clearly room for a 4th track (UP) between West Ryde and Rhodes, including over the John Whitton Bridge, once the new spans are constructed on the existing piers.  Regardless of the Inland Rail, there will still be a large volume of freight tragic passing through Sydney to and from the North Coast and North West, not to mention the coal traffic from Lithgow to Newcastle. It doesn't all originate in Brisbane.
Transtopic

The bridge might have space for 4 tracks but there isn't any room north or south of the bridge for 4 tracks between rhodes and west ryde. This isn't a freight line and any extra line through rhodes, meadowbank and west ryde will need a platform to go with it.

Modern residential developments means that the area for four tracks is long gone since platforms need to be of a larger size then those of 1920.

Car parking and many other things that were not an issue before are an issue in 2019.
  simstrain Chief Commissioner

In any case you don't need 4 tracks on this section. A third track for northbound is all that is needed so suburban services aren't affected.
  sydneyshortnorth Junior Train Controller

Location:
I'm with sims on this. I know this bridge well. Today's two live spans alteady fill exactly half of the cappings of the existing, pre-planned, (oversize) piers with no margin (I went down to look at it today). Have a vertigo-inducing look ot the down/up-river side if you're in any doubt. Doubling the spans would allow no space (the traditonal six-foot) between rhe existing and any new pair of tracks. It would simply butt the ends of the existing down-line sleepers right up against the new ones. Oops! One new northbound track do-able? Yup. North and South together - Probably not.
  UpperQuad Station Master

Location: 184.8 miles to Sydney
I'm with sims on this.
sydneyshortnorth
I’m with Sims on this, too. When additional spans are placed on the western side of John Whitton bridge, they’ll topple into the river. The cuttings for 4 tracks that were already built throughout have shrunk, and Australia has lost the technology to construct platforms where a carpark currently stands. Besides, there are new NBN cables in the way.
  simstrain Chief Commissioner

4 tracks in 1950 is completely different to 4 tracks in 2019. More space is required to meet modern safety standards and as I mentioned before platforms need to be larger to handle traffic and provide disabled access in the form of lifts. All this equates to 3 tracks from rhodes to west ryde.
  arctic Deputy Commissioner

Location: Zurich
Just to add what Infrastructure Australia thinks stage 2 of NSFC is

The candidate projects for the second package include Rhodes to West Ryde quadruplication and a third track between Thornleigh and Hornsby.
Infrastructure Australia
from https://www.infrastructureaustralia.gov.au/projects/map/?activeProject=5c645d1155da5a0016bd59b5

It goes on to say the prelim design is complete, so I suppose they figured out the problems

The New South Wales Government has completed a preliminary design for Rhodes to West Ryde quadruplication. A preliminary design for Thornleigh to Hornsby Third Track is being progressed.
Infrastructure Australia
cheers
  Transtopic Assistant Commissioner

Just to add what Infrastructure Australia thinks stage 2 of NSFC is

The candidate projects for the second package include Rhodes to West Ryde quadruplication and a third track between Thornleigh and Hornsby.
from https://www.infrastructureaustralia.gov.au/projects/map/?activeProject=5c645d1155da5a0016bd59b5

It goes on to say the prelim design is complete, so I suppose they figured out the problems

The New South Wales Government has completed a preliminary design for Rhodes to West Ryde quadruplication. A preliminary design for Thornleigh to Hornsby Third Track is being progressed.
cheers
arctic
Exactly. I'm puzzled why all of the naysayers, and sims in particular, are so negative about it.  I actually went there again today to check it out and there is no question in my mind that the John Whitton Bridge can accommodate 4 tracks.  

From my observation, the existing steel box girders don't quite take up half of the piers width.  It is also obvious that the O/H masts which are in place allow for 4 tracks.  There's no reason why concrete box girders couldn't be used for the additional tracks if the welded steel box girders are no longer possible.  It's not exactly rocket science.

I refer to the following quote from the NSW Office of Environmental Heritage with regard to the John Whitton Bridge.

"Limitations of the old Meadowbank Bridge had been recognised prior to World War II so plans were drawn up for its replacement as part of the quadruplication of the Main North Line.  The concrete piers were completed on the eve of the 1952 recession and work was suspended for 20 years.  By 1972 when a new bridge was truly a necessity, the new technology of lightweight steel, welded box girders offered a much cheaper and more elegant solution than the heavy, visually dominant trusses.  It was now possible to accommodate quadruplication of the line on the existing concrete piers, which were widened by a concrete cap to suit 4 tracks, but only 2 single track, steel box girder bridges were built and came into service in 1980.  These make up the John Whitton Bridge".

I rest my case.
  UpperQuad Station Master

Location: 184.8 miles to Sydney
The bridge might have space for 4 tracks but there isn't any room north or south of the bridge for 4 tracks between rhodes and west ryde. This isn't a freight line and any extra line through rhodes, meadowbank and west ryde will need a platform to go with it.

Modern residential developments means that the area for four tracks is long gone since platforms need to be of a larger size then those of 1920.
simstrain
Sims clearly has no idea. If space is such a big problem, staggered platforms will gain at least 6m lateral clearance - problem solved.
  Transtopic Assistant Commissioner
  simstrain Chief Commissioner

Sims clearly has no idea. If space is such a big problem, staggered platforms will gain at least 6m lateral clearance - problem solved.
UpperQuad
You can stagger all you want it ain't going to change the lack of space for 4 tracks through meadowbank or rhodes in 2019 or later. Not only that but I now have several people supporting my argument with some facts.

I never said the bridge couldn't take 4 tracks. Meadowbank station and the cutting leading in from the south is a problem. Where are you going to put the fourth track at rhodes. Whatever space was there to expand in 1950 is gone in 2019.

There are 3 platforms at west ryde and 3 at rhodes and so all that is needed is a third track.
  Transtopic Assistant Commissioner

Sims clearly has no idea. If space is such a big problem, staggered platforms will gain at least 6m lateral clearance - problem solved.
You can stagger all you want it ain't going to change the lack of space for 4 tracks through meadowbank or rhodes in 2019 or later. Not only that but I now have several people supporting my argument with some facts.

I never said the bridge couldn't take 4 tracks. Meadowbank station and the cutting leading in from the south is a problem. Where are you going to put the fourth track at rhodes. Whatever space was there to expand in 1950 is gone in 2019.

There are 3 platforms at west ryde and 3 at rhodes and so all that is needed is a third track.
simstrain
Sims, what's your problem?  I am mystified why you are so antagonistic towards a fourth track between West Ryde and Rhodes.  There clearly IS room for it, even though additional earthworks will be required.  The fact that there are currently only 3 platforms at West Ryde and Rhodes is irrelevant.  There is room to construct the additional platform faces within the rail corridor, just as it was with Cheltenham and Pennant Hills with construction of the Third Track from Epping to Thornleigh and at Concord West with construction of the freight line (Fourth Track) from Rhodes to North Strathfield.  The Third Track extension from Thornleigh to Hornsby will also require new platform faces at Thornleigh and Normanhurst.  It's not a major issue.  You obviously haven't bothered to read the Infrastructure Australia submission, which clearly proposes full quadruplication between West Ryde and Rhodes.  Considering the relatively short distance involved, it would be ridiculous if this wasn't a primary objective of this project.
  NSWRcars Chief Train Controller

Whatever space was there to expand in 1950 is gone in 2019.
simstrain
No space has “gone” since 1950. If you have any doubts, go to the LPI SIX viewer https://maps.six.nsw.gov.au/ and under Map Contents turn on Lot Labels and Lot Boundaries, and this will reveal the railway corridor. You may be able to see some of the 1950s work on the aerial imagery. It will be clear that both approaches to John Whitton Bridge abut public roads and park, so if any corridor widening is required to accommodate new works, it will be done by boundary adjustment. It should also be apparent that there is ample room for required works at Rhodes, Meadowbank and West Ryde stations. Where 1950s work is deemed unsuitable, the design will be changed. If any new works cannot comply with current standards, solutions will be found and risks mitigated, just as they were with John Whitton Bridge in the 1970s.
  simstrain Chief Commissioner

I'm not arguing about the bridge Transtopic. I know that can handle 4 tracks but exactly where are you going to get the fourth track through north of the bridge especially at meadowbank. Someone was talking about offsetting the station but the truth is that to make room for four tracks it is going to require moving the station 100 metres to the north. This will be extremely expensive and what will it achieve in any case. There are quad sections both north and south which allow overtaking of locals by intercity in peak hour.

There are 8 suburbans in peak hour in this area and 4 intercity services and they overtake the locals on the quad sections that already exist on the line. It's not like the northern line is stressed even with 2 tracks segments at the moment. The third track is only needed for north bound freight trains to give them a non stop run and to provide an alternative in case a train breaks down.
  UpperQuad Station Master

Location: 184.8 miles to Sydney
I'm not arguing about the bridge
simstrain
Sims, please stop arguing, relax, and don’t worry about where the fourth track will fit. Space was reserved back in the 1950’s, is still there, and won’t be going anywhere. In any case quadruplication isn’t required for the current timetable, and when the time comes, project engineers will consider your feasibility study and find a solution that is not too expensive.

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