Concrete Sleepers for 7-1/4″

[Gerald WeareParticipant @geraldweare85524]

I have a vague memory of seeing a fairly recent ME article on making sleepers from concrete/cement, but I’m darned if I can find it.  Does any one have a reference they can give me?  Failing that, any experience with concrete sleepers that you’d care to share would be appreciated.

Note: this is specifically about a ground-level 7-1/4″ track.  There is a decent amount of stuff on the web about standard gauge, but things don’t always scale…

 

Thanks!

[PeteParticipant @pete41194]

I’ve no hands on experience with 7 1/4″ gauge or any railway sleepers, but fwiw. I’ve broken and loaded trucks with multiple thousands of tons of both concrete road surfaces and sidewalks. Concrete is extremely strong in compression as long as it’s fully supported on a highly compacted crushed rock base material. It’s also easily broken in tension such as having any voids under it in that rail bed and then having heavy locomotives crossing above any unsupported areas. It’s a quite brittle material in it’s cured state, and in the right conditions easy to break. Adding steel as reinforcement and then cast the concrete around it would help a lot.

And concrete once cured isn’t a one type fit’s all uses material. Changing the rock and sand type and size, the cement in higher or lower proportions, how dry or wet the mix is, or even some of the more specialized additives used today in concrete can very much alter it’s strength, weight or amount of flexibility it will have before it breaks. One would assume your project is going to require hundreds if not thousands of those concrete sleepers. You really need to be asking a proper concrete expert your questions just to avoid any costly errors. Any batch plant that mixes and loads concrete trucks for delivery to the job site will almost always have at least one application expert that might be willing to advise you. Bringing a box of doughnuts or I guess in the UK, cakes along with you for your visit might help to get the best information and cooperation since I doubt your going to paying for or have any full concrete truck show up to load your probably limited amount of forms. You’ll also need to research the best release agent to apply to the inside of those forms so they can be easily released from the semi cured concrete and then reused. But concrete is also fairly expensive with usually a lot of time involved. Just like building a house, a strong and firm foundation isn’t optional. So the preparation below your rail bed and the bed itself is key. And that compacted rail bed absolutely requires a dry natural soil type under it as well. In construction, any soil that will allow plant growth is generally referred to in North America as a biological soil and none of it should ever be present anywhere below your rail bed because it’s seriously weak and has very poor compaction, any added water from rain will further weaken it even more. Without removing all of it and also ensuring good water drainage, both the rail bed and those sleepers will be guaranteed to fail given a bit of time. I hope some of this helps what your trying to do, or at least gives you a bit more detail about where to find better information than I can offer.

[DC31kParticipant @dc31k]

There is an index for Model Engineer here:

http://www.ropewalkview.uk/me_index.html

Download the latest version of it (http://www.ropewalkview.uk/data/181-230d.zip), search for ‘concrete’ and one or two things pop up. They are nearer the end of the file than the beginning so that supports your ‘fairly recent’ recollection.

Perhaps you could give an overall size (length x width x height) of the item plus a brief word on what, if anything, would be cast into the sleeper.

[Stephen Wessel 1Participant @stephenwessel1]

I wrote a series in ME about this starting in No 4621 Sept 2019. Aimed mainly at 5″ it also applies to larger gauges.

Briefly, the high strength concrete is glass fibre reinforced. Very easy to do, very cheap compared to plastic or wood and extremely stable low maintenance track. I have 1/3 mile most of it 3 – 4 years old and zero deterioration or breakages. Highly recommended.

[Werner SchleidtParticipant @wernerschleidt45161]

The Zürich steam model club use on his 5 inch layout concrete sleepers with glass fibre.

Please look here     https://www.dmc-ch.ch/    One of theire problems is that the dowels for the attachment apply problems by water intrusion and cracking in winter. Now they seal with epoxy in addition.

Werner

[Werner Schleidt]

On Werner Schleidt Said:

One of their problems is that the dowels for the attachment apply problems by water intrusion and cracking in winter.

As an alternative to sealing (trying to keep the water out), do not make the place where the water enters into a bucket (inadvertently storing the water once it has entered). Make it into a pipe, so any water that gets in can also get out (care not that the water enters, but care very much about encouraging it to leave).

[Author]

Posts