Wednesday, 5 September 2018

Kyeamba Creek Bridge



The Kyeamba creek flows from the hills near the Hume Hwy south-west of Tarcutta, (near the Tumbarumba road intersection) for a distance of 66km before ending up in the Murrumbidgee River.  The Tumbarumba railway branchline crosses the creek just west of Ladysmith.


Kyeamba creek is but a muddy puddle in March 2017.  Whilst I was not able to actually measure the rail height above the water, I have estimated it at 21 feet.
Another shot of Kyeamba creek, photographed from the bridge, showing a typical creek bank, and vegetation

The Kyeamba Creek bridge is a 6 x 24’ span NSW timber trestle, with concrete abutments.  A small tributary of Kyeamba creek is crossed by a 3 x 24’ span trestle close by the main bridge.   

The last trains passed over the bridge in the late 1980s.  The bridge fell into disuse, although there was a later failed proposal from Tumba Rail to reopen this section for Trike rides.    It was last year, before I actually got to inspect these bridges.   My visit to the main bridge was unfortunately cut short, as I had disturbed a wasp nest, and they were not too pleased with the intruder, forcing me to make a tactical retreat.
Looking towards Ladysmith.  Checkrails are prominent., and also are spiked directly onto the sleepers, rather than on sleeper plates - similar to the Murrumbidgee River bridge.   The shed on the righthand side is part of the automatic water flow measuring system on Kyeamba Creek, used by the Bureau of Meteorology.

The first pier of the bridge holds the rail approximately 8 feet above the ground.  The ladder is part of the automatic water flow measuring system.  The wasp nest is hidden under the sleepers close to the ladder.  

The concrete abutment



The small tributary trestle was in far worse condition then the main bridge.  One of the embankments had been washed out in the big storms of 2016, and the rails had been left dangling in mid air.  But there was enough left to see what once was  present. 

The small 3 span trestle around 200 metres to the west of the main trestle.  This unnamed stream had caused a significant wash-a-way in the storms of 2016 

Closeup of the damage.  The main railway support piers survived but the embankment, and its supports had been washed away, leaving only the stumps.  The rail, and a few of the sleepers have been left suspended in mid air

The pair of intermediate piers are resting on concrete plinths, and these look in good condition

The timber abutment at the other end of the trestle is also collapsing, but 30 years since the last train, and probably over 40 years of no maintenance, this is understandable


Many years ago, I bought the Ironbark models NSW trestle kit and extension, and started construction of an eight span trestle bridge for a former layout.  I never finished this model, before a relocation forced me to tear the layout down.   However, I kept the part built kit.
My intention when designing the layout,  was to reuse, and complete the kit without modifications, as I like big spectacular bridges,  but the further I am heading up the prototypical accuracy modelling route, I realise that the bridge kit needs to be rebuilt.

2 spans and an abutment of the Ironbark models NSW Trestle kit that I built over 20 years ago.  I am hoping that I can use this section for the small tributary trestle, as the abutments look similar, and are the approximately the same height.  The longer pier will need to be replaced, rather than just cut down to size.  The reason for this is that the angled beams have been rebated into the round piers.  The other pier is really close to being right, but I will have to make a determination later


The Ironbark models kit has great diagrams to help with the construction of the trestle, but the Data Sheets (Sheet P4) is the reference for  the  24’ span NSWGR trestle bridge.  These plans contain all the bridge details I need, except the concrete abutments, and the height of the piers on the Kyeamba Creek bridge.  However, the end abutment drawing seems to be close to style found on the washed out tributary bridge. 
The first step was to draw up a diagram showing the concrete abutments, and pier heights. 

Sketch of the Kyeamba Creek trestle - showing details of the concrete abutments.  These sizes have been guestimated from photographs.


My next challenge will be to try and remove the trestle piers from the already constructed bridge deck, without doing too much damage to the deck, and construct the concrete abutments.
Until next time, happy modelling

3 comments:

  1. Rob

    When you build your bridge you might find these useful, 1.5 inch square nuts on 3 inch square washers.

    https://www.shapeways.com/product/55GMVEWWZ/ho-272x1-5-quot-sq-nut-bolts-with-3-quot-sq-washers?optionId=65254668

    Ray P

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  2. As always Rob, you keep raising the bar higher! I love exploring old railway lines such as this, and I'm sorry, but it was hard not to laugh picturing you scurrying back up the embankment with tape measure in hand. I'm sure one day this will only add to the story behind your finished bridge! Looking forward to your next update.

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  3. Hi Rob,
    Bridge is looking good. Looking forward to the finished product.

    ReplyDelete