Question on filling in an existing timber trestle

Came across article with pics courtesy of Wyoming Co Historian and WNY Heritage Magazine - one being of the B & O ROW at Rock Glen in the Town of Gainesville.
Referencing the ‘wooden trestle that was later filled in”.
Always figured filling in would alleviate having to worry about wood but how would you be able to pack gravel under the rail bed firmly enough to provide a solid base?

Maybe I’m thinking this through too much .
Mark

Apparently you just dump fill material from a train on the trestle. See https://web.archive.org/web/20140320042 ... ockwd1.htm and https://www.youtube.com/watch?v=Jp8R0YJ8NpI

Nice film- what a heck of an endeavor.
In trying to understand -instead of dumping from the main trestle apparently building smaller ones along side than building up from them?

Then would constantly be rebuilding the Spurs higher as the fill increased ?

A lot of the film was digging out the stream bed ?

As more material is dumped, the material dumped on top continuously increases the pressure on the material below, effectively compacting the earth as it goes. I imagine once all the fill is in and the vibration of passing trains is added, there will continue to be a small amount of settling that continues for some period of time, which will require some additional material to be added.

Yes, as has been stated, dumping the soil a bit at a time does provide some compaction as the fill gets higher the soil below will get more compact.

At some point, at least with some wooden trestles, the top the the trestle would be dismantled when placing the final few feet of fill and then ballast and new track.

The railroad would definitely need to go back and bring any low spots up to grade as the fill continues to settle. As long as the fill was not in a swamp it should only take a few years for the settlement to stop.