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#381 ·
CliffyJ said:
I hear ya Dirk, but for really undulating-ground trestles, it's still a chicken-and-egg thing. Like, you put the pavers down, or pour the footings, and hope that the measurements result in a bent that is exactly the right height....

I like what Alan's doing, in setting the top as the datum, and trimming the bottoms.

Still not sure about the casting in place though, no matter what the concrete type is. Though that's important too, thanks for reminding me of that stuff TW John.

So at the risk of sidetracking Alan's progress, and it is HUGE and INSPIRING, that interface between timber and footing is important. Like TW said, pilings are driven in; and, from what I've seen, cut timbers rest on a sill beam.

For me, to a large degree, things boil down to drainage. It's tough to make the lower part of the bent 100% drained, while anchoring it.

Here's a thought. Mark each suspended bent for where it will need to stop at the bottom. Take them off, and cut them short for the sill beam (say, 1/2"). Band them back onto the deck gauge. Somehow strap a piece of 1/2" plex to the bottom of each bent, as an upper form surface.... and when the crete is poured, add the sill beam to each bent. Maybe embed some SS nails in the crete for indexing the sill beams.

Naah, heck with that, that's too complicated....

[edit]
Interesting idea TW with the split footing. You think a CementAll anchor on each bent would be light enough, after it were made thick enough to not crack?
Click to expand...

As you noted the timber bents rest on a mud sill. I was thinking a footing an inch at least thick. The second pour is to bring the ground up to the good foot. Covered up you only see the good and the bents are stable.
I'd likely use rubber cement to 'attach' the foots temporarily, the idea is to locate the sub footings. I'd leave the final assembly as gravity held to allow for expansion/contraction.

John
 
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#382 ·
While my timber trestle is not as long or high as Alan's, I have used the paver stone method with success. The trestle was built off site with the bents being absolutely level and even along the bottom and top. The trestle site was dug out then weed block and tamped paver base was added. I placed the pavers via trial and error until I was satisfied that they were all even and level after being tamped in place with a rubber mallet. This required the addition or subtraction of paver base under the pavers.
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Note the prebuilt trestle in the lower right and the various levels in the lower left. Also the rubber mallet for making those fine adjustments. :rolleyes:
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The trestle and tracks were set in place and checked for level. At this point no major adjustments were needed.
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I made sure that the bottom of each bent was fully resting on it's respective paver. I recall that the step pavers at each end required some minor adjustments.
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I then added pond stone that pretty much covers the top of the pavers.
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After a long hard winter with temps down near zero the trestle showed no movement when trains started running this spring.
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#383 ·
I completely agree with John regarding allowing for unforeseen movement..

Both ends of a trestle are kinda tied inplace by the end retaining walls.. and track..
But the rest is subject to the properties of expansion.. as are every building material we use outdoors to build our pride n joy layouts..

Better to let trestle weight rest on a footing.. yet not be bound by them...

Dirk
 
#384 · (Edited)
Really nicely done, Wayne.

And TW John, good ideas, I'm liking it. One could further consider pre-casting the upper & exposed footer, and cast in a couple of SS nails. The sill beam would have a couple holes drilled to match, and can come away from said footer.

After using Alan's method to mark and chop the bents, the sill plate can be permanently installed on the bents. The upper footer is wired on w/ ss wire, and serves as the ceiling for the concrete base (which is concealed). The crete is poured up to the precast footer, which always remains on the concrete. Once set, the wires are clipped, and the entire bridge can be taken away (with a helper or two). The sill plates are indexed, yet there is full drainage for them (and the rest of the bents).

[edit: I just realized that John's rubber cement would take the place of my SS wire]

True, a lot of trouble. Clearly, the easier method would involve burying the timbers. On pavers. Just opining for fun though.

===>Cliffy
 
#385 ·
Trouble with fast and easy; the resulting repairs never are.
John
 
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Discussion starter · #386 ·
All great ideas and using sliced up pavers as footers should work. With the rain we've been getting the recently filled (Dec and Jan) area of the bump-out has compacted about 1 inch which isn't bad. How does using pavers as the main support then filling around the bents with 1/4 minus or next size up so it drains better an then topsoil over the gravel sound? Was planing on glue/staple of 1/2 x 1/2 at dirt level to strengthen the legs and spread the load. So many choices and ways to do things
 
Discussion starter · #389 ·
Yesterday was 6 weeks ago but vacation trips intervened. With the original three in place I've been adding on. As each new bent goes into place I'm learning a few tricks to speed things up. Still takes about 1/2 hour per bent to keep the grade at 1.5% (plus or minus 0.1%). Work in the morning and watch it rain in the afternoons. The first section of 11 bents is now in place and ready for stringers to be added once I complete the next section over the bump out and stopping at the first bridge.
Humm Photobucket not letting me copy and paste photos as usual since I went to Windows 10. :) Photos to follow as soon as I figure this out :)
 
Discussion starter · #390 ·
Discussion starter · #394 ·
If all else fails go back to MS Paint and do a resize. :) In addition to fighting with program "upgrades" I've been working on the trestle. Learning some techniques to reduce the time it takes to put the footers (12" pavers cut into thirds - Dirk) and get them level, place the bents and keep them semi-in-place (rubber cement - Cliffy), adjust to meet grade requirements, and attach the stringers (Tite Bond II and pin gin - Lots of people). The result is the "big pile" of bents are now in place along the edge the bump out (Dirk's - You know what would look cool is...) to where the tracks turn north along the edge of the raised plateau.
Thumbnails show the first section done(1), Bents stacked ready to be installed (2) Completed section 2(3), Train eastbound toward the Northbound curve (4), and looking west to where a mountain will form the entrance to the Hole-In-The -Wall and mine area.
Sections 3 and 4, along the east side of the plateau, include 2 bridges needed to cross over the 2 outer main lines and the beginning of the grade up to the plateau. Sections 3 to XX will require about 150 more bents.
 

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#396 ·
Looking good Alan!
Following instructions; Imagining a mountain... Behold the Russian Steppes!
A nit picker will tell you that timber (cut lumber) bents need a mud sill... while piles made from tree trunks were driven into the ground. Poor Cliffy may be miffed when I suggest you carry on, as you are!.
John
 
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Discussion starter · #397 ·
I plan to put in "mud sills" once I have sections in place and dirt/gravel/ground cover leveled. Thinking of using 1/2" x 1/2" timbers attached across the bottom of the legs on both sides with end caps
 
#398 ·
If I picture what you said correctly; you are going to add horizontal bracing and call it a sill? That will work for Some of the people...
The sill goes between your bent and the pavers.... just saying.... after a monsoon they may not be seen again! So it's not a big deal...
John
 
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Discussion starter · #400 ·
You are right on about the monsoon, TW. Several places on the site now have ballast 8" away from the tracks. I'm going to do a rough "level" put down weed block and then cover that with earth-colored gravel. Hopefully that will keep the braces above ground. I expect they will tighten up the bents even if they do disappear next year.
 
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