Picked out my site and just finished initial survey: overall, it is slightly over a 2% grade from front to back (50 ft) and a gentle 4% from right to left 9(25 ft with 2% drop in last 2 feet at boundary).
My question are: 1. There are some low, mushy spots where removed bushes were so how do I fill these to get firm area for rail yard? Do I bring in fill and tamp it until firm and level? 2. On the side boundary, I need to level it somewhat but that will leave a 2 - 3 inch fall off. I plan on using the outside boundary like a river (since it IS a river when it rains) but the rail line will be the "bank" for a
3 foot section of this 50' . Do I use the ballast as the "shore"? Timbers? Gravel? Bigger rocks? This is a Georgia coast rail so rocks are not typical.
Doesn't the bank need to be porous or else I create a dam? This low area is a de facto "ditch" (albeit only 3 - 4 " lower than surrounding area) that drains my and my neighbor's yards down toward the marsh. At the marsh edge, it abruptly drops 36 to 44 inches. - if I squared it off, I would have a scaled Niagra Falls!
Rocks may not be the norm...but they are doable...trestle and bridges allow water run-off to cross from one side of your tracks to the other side...
Embrace your areas needs with mother nature! You'll be happier with results....
Set a yard area...add solid fill..flat and broad enough to provide your dream yard. Allow paths for drainage ..even moving low spots to new locations...think dry washes...
Planning is imperative..
A request for a photo essay of your layouts future location is helpful to us..your asking for help...help in creative solutions for your railroad!
Are you running old western rr?
Are you running mid century times??
Are you running modern ...to days present scene as a rr??
Sounds like your after this 25ft x 50ft area... Is it larger?.. Can it be larger?
This is a process...thanks for asking for our help and thoughts!!
My plan is to finish a detailed survey then bring in fill to make some areas flatter for a rail yard then let nature sculpt the area while I plan the exact layout. I thinking early 1900's steam. I have two 25' X 50' areas on either side of my yard which will be connected by a 120' line running along the top of my 4' high retaining wall - separating my yard from the tidal marsh. When I get the first area ready for layout, I will put up a picture and RR track plan to get some feedback and ideas.
I raised all my areas up to waist height so I don't have to bend down. Seems to be a problem for all of us as we get older. I have made garden beds some 6 metres by 2.5 metres. If just got to build the bridges to join them up. This way I can create a different theme in each box. A bit more effort at first but worth it in the end.
If you have low spots due to removed brush, bushes or whatever you need to fill those in. However it is a good idea to make sure organic matter has been removed. The issue is the roots and so forth rot.and result in low spots as the rot compresses.
If the organics have been removed then you will still want to dig a trench down to solid gouging and then fill with stone dust or crushed rock. The thing here is the tripping out a bush loosens the soil which will eventually settle again. The other option is to tamp the soil to the same density as the surrounding landscape.
While slightly unrelated a good portion of my property is a sandy loam. The side walks in several places over the years have settled and tilted dramatically. This is actually a problem with all construction in the neighborhood. In some places it was so bad I had to replace the walkway. So to try to prevent a reoccurrence I dug down a good two feet into a different layer of dirt (it is pretty obvious) and then back filled with two feet of crush stone (#2 I think) and then laid concrete across that base for the replacement side walk. So far so good.
Interesting the state took a similar approach when rebuilding one of the local highways that wasn't all that stable and in fact was on somewhat swampy land. They literally dug a channel deep enough to bury the rather large bulldozers they where using.
In the end construction is all about your foundation. That foundation can be a road bed for a rail way or a sky scraper, either way you need to consider local conditions.
And if the 4% involves a curve, it gets worse!!
In a low area my friend used rebar and plastic pipe to raise the track in a trestle like fashion. Water flows freely under and this gets rid of the grade.
Just for an example, the STEEPEST mainline grade for the eastern US states is the Saluda grade on the former Southern Railway. It is 4% over most of its incline. There was actually a switch to direct trains into a "runaway" track (which was markedly steeper) should a train loose its brakes descending the grade. The switch was normally lined for the diverging route, and engineers had to give a special whistle signal before they got to that switch, to let the switch tender know that their train was under control. Then the switch would be set for the main route.
I suppose such an arrangement would be interesting to do on a model railroad, but it would consume an awful lot of real estate.