Id argue for the times this happens versus a decent dam style retaining structure to encase the embankment that thered be more than sufficient opening for water to course. Most of the hydro pressure is to the southern bank. I wouldnt envisage a problem. far cheaper than building new piers and such.In the early 1980's the approach trestles at the Up end near the Old stratford Junction Signal Box were shortened as suggested by earth fill, culverts and a single steel span bridge with concrete abutments . Shortly after the river flooded and the new bridge had one abutment undermined, The Avon management authority got involved and it was decreed no more replacement of bridge with embankment as not working . The bridge involved had the subsiding abutment removed and the structure was altered to two spans with a new centarl concrete pier, and a second deeper steel span (ex the old bridge at Maffra) was added .
As insurance possibly...throw some larger corri culverts between existing piers before filling.
To clarify - an upgrade from Class 3 to Class 2 requires re-railing with heavier rail, yes?In this case Traralgon - Sale is already 94lb rail CWR in recent years . The issue to bring it up to Class-2 is address weak bridges, intensive tie renewal/replacement with slimline concrete sleepers, improved ballast depth .
I hope that the re-railing at the three stations about to happen as part of the upcoming project would include this heavier rail. Not that any speed improvements would be gained at the stations themselves, of course, but any eventual improvement must start somewhere.
IIRC the only VLP passenger lines not with 94lb/47kg rail currently is Mangalore to Murchison East , and Kerang to Swan Hill . There is plenty of surplus 47kg rail cascaded ex RFR available to upgrade these two sections .The sooner that is done the better. Even with timber sleepers, with proper bolt fasteners (no more dog spikes!) you could get to class 2 track. All you need is a ballast top up to 350mm. Oh and there are sleepers from grey box ash and similar timbers available, so no need for redgum either.
Is the duplication of the Bunyip - Longwarry section still going ahead ?Mulder & Napthine promised a lot for PT when they felt the whistle of the axe falling . None of it had timelines on it, and we all saw how little they implemented of their own initiatives in their 4 year term . So would have regarded the promise as Alice in Wonderland stuff really .
Or was this a Napthine Government project, that went out the window (along with It's Government)
The sooner that is done the better. Even with timber sleepers, with proper bolt fasteners (no more dog spikes!) you could get to class 2 track. All you need is a ballast top up to 350mm. Oh and there are sleepers from grey box ash and similar timbers available, so no need for redgum either.Doubt you will find VLP putting any more timber sleepers into passenger lines . Rather a progressive installation of the slimline concrete sleepers as tie renewal cycles proceed across the passenger network .
Doubt you will find VLP putting any more timber sleepers into passenger lines . Rather a progressive installation of the slimline concrete sleepers as tie renewal cycles proceed across the passenger network .For the high volume lines I would agree. Plus essential upgrades such as Shepparton etc.. But for the Bendigo to Swam Hill section, I expect timber to be used in future. Don't get me wrong, I would prefer slimline concrete sleepers, but dollars and low traffic volumes will have an influence.
Concrete sleepers have a 50 year plus life and lower track maintenance costs .
So you have studied the actual bridge for yourself? Actually seen the beams and their construction and how something a bit not right is there?Here's the cock-up that skitz is referring to. The cantilever section is angled to the left, when it should've been to the right, to match the curve of the track. As you can see, it has resulted in something of a clearance pinch.
Here's the cock-up that skitz is referring to. The cantilever section is angled to the left, when it should've been to the right, to match the curve of the track. As you can see, it has resulted in something of a clearance pinch.
As for the flooding, here's some photos from 2007. It has flooded a couple of times since then.
http://www.signspotters.hobbiesplus.com.au/floods.htm
Here's the cock-up that skitz is referring to. The cantilever section is angled to the left, when it should've been to the right, to match the curve of the track. As you can see, it has resulted in something of a clearance pinch.
Is the problem that simple, by the look from this shot what one has here is a straight bridge section with a curved track on it. In this case all that re aligning the straight bridge section will do is shift the clearance problem to another spot. There's very likley no simple solution to this problem other wise it would have been fixed.It may look simple from the top, but the problem is that the piers are not under the join of that particular span.
woodford
The steel spans are of three vintages and this can be seen clearly in the flood photos .Unfortunately, I don't get ARHS Bulletin, so I've not seen the article. I'm sure I'd learn from it.
The straight wrought iron spans on the wooden piers , then some mild steel rivetted spans on the red brick piers and finally new mild steel spans on the concrete piers .
As explained previously as originally built the main stream passed under the old wrought iron spans on the wooden piers at the Stratford end, and the rest of the structure was wooden trestles . Then the main stream moved towards Sale and the steel spans on the brick piers were put in replacing high wooden trestles. Finally circa 1920 the concrete piers and more steel spans were put in on the Sale end again replacing higher wooden trestle structure .
Chris Banger wrote an excellent article on the history of the Avon River rail bridge at Straford in an issue of the ARHS Bulletin some years ago .
It may look simple from the top, but the problem is that the piers are not under the join of that particular span.If one looks at the top photo you can see quite clearly that the kink is not a design fault, rather just the way it is .
The pinch point between the spans shown in the photo from the train, is a few metres from the pier on the left of the photo above. It's not easily fixed without major works.
Above: One of the cantilevered sections showing the join of the spans.
As Kuldalai mentioned, the river originally went under the wrought iron spans with the timber piers. The river has gradually changed course with each flood and this section now only sees water under it during major floods.
Interpretive signage in the park at the township side of the bridge.
The wrought iron and timber pier section at the Stratford end of the bridge.
Trestle bent numbers 73 and 72 at the Sale end of the bridge. Originally, the trestle extended up to the highway bridge.
B67 said........Ummmm! I was only replying to your earlier comment where you said "Is it that simple". Granted, you then went on to say that it isn't or it would've been fixed earlier.
"It may look simple from the top, but the problem..............."
woodford comments.........
Errrrrrrrrrrrrr, the problem does not look simply and of course modifying any old structure is always a ____VERY____ difficult and expensive undertaking, thats why most such things are replaced totally.
If one looks at the top photo you can see quite clearly that the kink is not a design fault, rather just the way it is . Back to the top photo the steel span between the two brick piers is basically straight with a short overhang slightly wider than the main span on each brick pier. Then in the middle is a dead straight but slightly narrower canterlevered span . As such the available width within the structural beams for the track narrows slightly on the cantilevered span . At the Statford end the overhang beam creates a change of direction, this added to the narrowing of the cantilever span creates the situation shown from above in earlier photos. It is designed and constructed that way, it is not a design fault .I think I know what you're saying about the narrowing. But I've heard others say it's a fault - and it certainly looks to be. So I referred to it as such. The tight section appears to be only on one end of the cantilever. I'd have expected it to be the same each end. I'll wander down for another look when I get a chance.
All the pix ive ever seen regarding clearance niggles point to the height of the lower rail of a carbody. The Piers seem quite capable of standing for some time yet. I still dont see why effectively jacking the height of the actual track wouldnt solve some of these issues. Jettison the ballasted idea through the bridge and replace with effectively a new framework resting upon the older one. You could lift the rail height 200-250 quite easily I would suspect. Approaches to the main spans would need adjustements also but hardly rocket science. The bridge doesnt need to be rated for high speeds as theyd no necessary. Clearance is the issue. Bit like letting the air down on the stuck truck.. edit but I wouldnt think replacing the old wrought spans with new steel ones...or something was really that hard either Bridges are built everydayIf it was HO scale (or O scale in our case), you'd just turn the girder spans upside down and lay the track on what used to be the bottom of the bridge. But I suspect the full size isn't as simple as that.
In the early 1980's the approach trestles at the Up end near the Old stratford Junction Signal Box were shortened as suggested by earth fill, culverts and a single steel span bridge with concrete abutments . Shortly after the river flooded and the new bridge had one abutment undermined, The Avon management authority got involved and it was decreed no more replacement of bridge with embankment as not working . The bridge involved had the subsiding abutment removed and the structure was altered to two spans with a new centarl concrete pier, and a second deeper steel span (ex the old bridge at Maffra) was added .The second deeper steel span near the former Stratford Junction was actually an ex Lake Hume Sandy Inlet span.
Given the current problems with corroded Armco culverts they will not be using them again . In due course the long low wooden trestles over the flood plain will be replaced with a new structure of lesser number of spans .
Snip!Shows the cantilever off set heading the wrong way quite nicely. (as does the picture previously shown taken from the train)
A side view of the cantilever span taken the same time.
https://flic.kr/p/rhNw3t
Snip!
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