Today was a day of experiment.
When inserted, a concrete sleeper looks very much as above (this is before tamping and boxing, but in terms of the fastening down etc… It’s complete), but getting it in our track which has very little ballast depth has been of concern, so we set about working out what we could do.
Initially we set about doing things as we would for timber, scarifying to the depth of a timber sleeper (as set on the scarifier).But, and we knew this would be the case, you can see by the pic above that the pandrol lugs pretude above the sleeper top, preventing the sleeper sliding in.
We had two basic options from here, lift the track or dig a deeper hole.
Option 1 worked, we did have to jack up the track quite far and we were lucky ballast didn’t find its way under the adjacent sleepers keeping them up, but this method does work quite well, but it’s fairly time and labour intensive.
Option 2 worked also. We adjusted the depth setting for the scarifier and found the right high to be able to insert the sleepers without destroying the base below.
We ended up running with option 2 for most of the holes, as it was much quicker and we wanted to see if we were likely to be digging into the sub-base if we used this method. We didn’t in any of our 18 holes find that we’d dug too deeply, however we may have just been fortunate here and time will tell for other sites.
This beast, which gets talked about a bit here, really is essential to the resleepering process as it leaves a nice clean and square hole for the new sleeper.
We already knew this trick but we had forgotten and were soon reminded… Install the plastic pad on the sleeper before putting it under the rails! Here John’s doing just that to make sure we didn’t forget again.
Once the hole was scarified, gentle insertion with the excavator was undertaken. Pics above show the process, doing it this way prevents the concrete sleeper from damage as well as only disturbing the already loose dirt in the hole.
Once in, the clipping up process is quite straight forward (we’ll post more pics when there’s more hands to hold cameras instead of tools)
With the finished product (here freshly tamped and yet to be boxed up) looking very smart and secure, greatly reducing our ongoing maintenance of timber sleeper renewals!
Today’s efforts were very encouraging, with only 3 people and no preparation we were able to completely install 18 sleepers and have time for quite a bit of experimenting.
It certainly gives hope to getting 100+ installed in a day’s work with more bodies and a bit more of a systematic approach.
We’ll be out again this Thursday and Friday, re-railing. So please come along and help out, it’s always a great day out in the bush and we would certainly appreciate the help.
VGR Civil Blog 