CP Flog Subdivision

[Greyryder]

You could try something, like the latest Model Railroader has in it. The hinge is on a drawer slide, mounted vertically. You lift the hinge end first, then let the whole thing swing and slide down. The free end rests on a ledge, where vertical alignment can be maintained.

[Jeff AKA St0rm]

So after another busy season at the golf course it is starting to slow down and it is time to get back to the basement and some work on the layout. I have been working a little here and there throughout the summer but nothing worth posting about until now.

With my track still on backorder I started to work on building, roads and also I had enough track to work on my river crossing.

My “city” is starting to take shape with roads going in and building being placed. The road still needs lots of weathering but it is a start.







The river has a base layer of scenery and the trees are just in place temporarily until I get everything done around them so they still might move. Once I am happy with the back part of the river I will install the train bridge. I still need to build a center support for the bridge.







I have also started a kitbash with 2 George Roberts Printing.







And Lastly i airbrushed some clouds. I dont know if i like how they look but the good news is i still have lots of blue paint so i can always start over







That is all for now but I will post more often as things start to come together.

[mcjaco]

That's a very interesting Guiness building. 

[Philip H]

This is really nicely done.  The striping is excellent.  And yes a litlte weathering down the center will be icing on the cake, but honestly, not needed.

I don't think this needs a center support.  Perhaps a layer of class 3 rip rap below the footings (and not running all the way up to them).  But o center support.

[C855B]

... I don't think this needs a center support.  Perhaps a layer of class 3 rip rap below the footings (and not running all the way up to them).  But o center support.

Hmm. I do think it needs a center support. It's been decades since I knew how to run the calculations, but my edu-SWAG says the girder walls are not tall enough for the loading. They'd need to be about 50% beefier (or 25% shorter) for an unsupported span.

It would be OK for a highway bridge, but as it is it's too light for RR weights.

[wcfn100]

Hmm. I do think it needs a center support. It's been decades since I knew how to run the calculations, but my edu-SWAG says the girder walls are not tall enough for the loading. They'd need to be about 50% beefier (or 25% shorter) for an unsupported span.

Wouldn't it then also become two bridges?


Jason

[C855B]

Typically, yes. It's simply easier and lower cost to transport smaller spans to the site. But there's nothing I know of that would keep you from doing it with one big span and piering the middle. :shouldershrug:

I'm sure it's happened (Ed's Law applies here). Engineering does their calcs, sends the order off to the bridge company, company can't get Grade [whatever] steel in the size they need but goes ahead anyway, RR finds out, chief engineer blows a gasket and then goes back to his people telling them they'll have to design a center support. I've seen similar scenarios firsthand when I was working for DOTs. Not pretty.

[Jeff AKA St0rm]

The Bridge is 120' long so i think it needs something in the middle. I am no bridge expert but i am sure it will look safer if it has a support. 





This what i am using as a reference. It is hard to tell but it looks like 4 bridges that have been welded together. I don't see any seams. If that is the case I can make it look better with the center support with some bridge shoes. I will look tonight on my way home to see if i am missing somthing.

[Scottl]

Loading is one matter, but it would be unusual to put a pillar in the middle of a river like that.  The pillar would deflect flow and lead to undercutting of the banks. 

Given the span and the channel profile, a truss bridge would be more likely.  Alternatively, a shorter mid section (say 60 or 80') and two pillars at the banks with approach spans.

[Jesse6669]

Loading is one matter, but it would be unusual to put a pillar in the middle of a river like that.  The pillar would deflect flow and lead to undercutting of the banks. 

Does it have to be a river?  Why not a divided highway as in the pictures?   Or a river on one side, and a road along the other, so the center pillar wouldn't be interfering with flow?

[Philip H]

That span over the highway is more then 120 feet. Heck the single span over the one set of lane is probably 80 or so. The river definitely looks like a high flow channel - any pier In it would be cause serious erosion under the abutments.

[Jeff AKA St0rm]

ok so the prototype is the Red Hill Valley parkway in Hamilton On. The tracks go over the Highway and also i small river that has a light flow. The river banks look as there do because it is part of the Niagara Escarpment. In the prototype the river has been moved so they could put the highway in and is now lined with concrete. I was thinking of building a concrete river bottom under the bridge where the support will go, so it will not be a normal river bottom but a man made one.

[Scottl]

You could definitely do that.  Most diverted or straightened channels are not lined with concrete.  Common treatments are gabions and the selective use of concrete (especially near other structures like bridge pillars).   Coarse rip rap can be used too but most often the banks are just minimally graded and vegetated for erosion control.

In that setting, the last scenario would be most likely.  I don't think I have seen concrete channel in Ontario- not enough runoff and ice would not be an issue.

[Jeff AKA St0rm]

I knew i had seen bridges like what i wanted to do and here is a proto pic. Ed's Law at it best



Thanks for the ideas guys but this is how i always saw it working.

[wcfn100]

I never saw the issue with having a pier in the water. It happens, I've seen it on the prototype like you posted. Having a pier support the middle of a single span however, is another issue.

I'd like to see an Ed's Law on that.


Jason