Trestle Placement and Anchoring

[Anonymous]

What are good options for placing thresltes? I figure at least 1 every 1' but how is the best way to anchor them in the ground? One section of my layout is going to have a long (15' aprox) trestle. The grade will be just about 0% but the ground drops a total of 14" from one end to the other. Thank you!

[tangerine-jack]

Best way? HAHAHAHAHA!!!! Now you've opened a can of worms! There is no "best way" for anything in the garden, just what works for YOU.

I am building my anchors out of 4" PVC pipe, 12" long sunk into the ground, filled with concrete with a stainless steel bolt set into the top to anchor the bridge. I've used similar construction on non-garden RR things, but it should work as well for a little model bridge. Now if you have larger bridges, you may want to use real world contruction techniques, grab an engineering book and have a look-see.




[oX)]

[ttrigg]

TxPitmaster:

Like TJ just said, the right way is what ever works for you.

Having built at least forty (40) Timber Trestle Bent Bridges in the scale of 1:1 (FULL size, to drive M60 and M1 main battle tanks across {that's 23 years in the U. S. Army Corps of Engineers}) I can say this. IF you have solid ground to work on, lay in some footers, across the footers lay in a "sleeper" (same size as the cap on top of the bent) across the footers, attach your posts to the sleeper then the cap on top of that. It requires Transverse bracing (an "X" brace on the timber bent) and Longitudinal Bracing (an "X" brace connecting one timber bent to the next.) If on the other hand your ground is not solid enough for this then dig a small trench 3 times as wide as the thickness of the "lumber" you are using. Position your timber bents in place with lots of temporary bracing and pour in some cement. You might run a 2x4 from one abutment to the other and attach the bents to that until the cement cures. If you use the cement method make double sure that everything is in the proper place before pouring the cement. You can always use crushed stone to cover the cement as "decorations." A friend of mine recently e-mailed me that one of the bridges we built in 1979 was just pulled down this past summer and replaced with a concrete bridge.

Let me know if you are interested in this technique and I can post a couple of drawings.

[Capt Bob Johnson]

What I gather you are asking is how far apart should the bents be. A foot would probably carry the load, but what about looks? If you're trying to have a trestle that looks like real, you probably need to look at some pictures of the real thing! Judging from some that I have seen the real things are placed between 12 and 20 feet apart! Do the math and obtain your scale separation! I'd make a jig for making the bents.

There are many ways to anchor them. You don't want to provide Thanksgiving Dinner for your friendly termites, otherwise you will be replacing all that work pretty frequently!

[Anonymous]

Thank you all. I should have my plans in soon from Garden Texture so Ill be knocking out a few in the next few wekks and trying your suggestions. Since I have a lot to 'plant' Ill figure it out soon! Thanks again!

[kstrong]

QUOTE: You don't want to provide Thanksgiving Dinner for your friendly termites...

If they were friendly termites, wouldn't they be eating your annoying neighbor's house instead? [;)]

I've seen a few different methods for securing bents used. The one I'll probably use involves sinking a brick into the ground as a foundation, then gluing the bent to that with some silicon or polyurethane adhesive. On my dad's line, we nailed the bents to a short lenght of pressure-treated 2x2, and filled in underneath it with pea gravel. It's been in place around 18 years now, without any signs of rot. We actually hung the bents from the stringers which support the track, then filled in the ground below them. This made sure the track stayed perfectly even. The bents were installed individually, then the bracing between them was added once the bents were secured. (Photos, see current issue--December 05--of GR)

Later,

K

[Capt Bob Johnson]

K,

Touche, Messouir Pussycat!; Hoist on my own petard!

The floating Capt.

[cacole]

I have a 100-bent trestleworks on my outdoor layout, and placed them 6 inches apart for no other reason than appearance. Each bent sits atop a brick, and is glued down with silicon caulking. Stringers on top and the sides of the bents fastened with carpenter's glue and an air brad gun keep the bents from moving. I made my bents out of cedar fence pickets ripped into squares for the posts and top stringers, and used redwood bender board for the cross-bracing and side stringers. My bridges are also made from cedar fence pickets because they are plentiful and relatively cheap here in Arizona.

The results can be seen at http://members.cox.net/cacole2