I have a question on "How it's Made" in regards to bridge piers. I started scribing in top detail after penciling in some locating marks on the tops of my piers that I squared in a mill. My question is, do they fill the center with concrete & random stone, & make a nice level top in the center? (as I have illustrated). Or, is it field stone all the way through the entire pier? I'm asking as I wonder if I should continue scribing in blocks on the top or just leave it like the picture & paint the center slab a concrete color. I guess in my mind it could be done either way in real life. BTW, this is my initial primer coat, I do plan on filling the bubble holes & extra/accidental scribed lines, I may even chisel in some stone irregularities as well. Any info & suggestions would be greately appreciated & put to use..
First, I don't know how they did it in real life, but I am fairly certain that the top was flat and of either stone or concrete. The way I model the tops of piers (no matter what material is simulated) is to dust on either ground foam or fine ballast after the bridge is installed. I think in most cases, once the bridge is in place, they don't send someone out to sweep the tops of them off. They just leave what falls on them there.
Elmer.
The above is my opinion, from an active and experienced Model Railroader in N scale and HO since 1961.
(Modeling Freelance, Eastern US, HO scale, in 1962, with NCE DCC for locomotive control and a stand alone LocoNet for block detection and signals.) http://waynes-trains.com/ at home, and N scale at the Club.
Elmer,
Thanks for your response & suggestions, I may never would have thought of that.
My motovation for adding some top detail is that I'm adding a truss bridge (center) & two open girders for feeder units.. The ballast will not be close by, unless I do a bad job of laying bridge track! hah hah... Let me add a shot of the spans when I was sizing my base board..
If paint dries & I work hard I may be able to shoot this shot with it up on the piers & abutments later or tomorrow. Thanks again!!
I recall when they took the piers out from the PRR bridge across the Maumee River here. After all of the steel and iron work was removed, they set drilling rigs on top of the piers and drilled down through them. The outside surfaces looked like cut stone blocks, but I am not sure what the interior was. The bridge was installed in 1872, so it is possible they were cut stone all the way through. They loaded the borings with dynamite and blew them to pieces leaving them on the river bottom.
Jim - Preserving the history of the NKP Cloverleaf first subdivision.
Jim, That would have been something to watch!!! KABOOM!!!!!
This shows the pier with additional detail scribed & carved on top, with both spans on it. The Truss Bridge is on a temporary wood blocks until I cast some stone risers. Staring at it & then staring at the pix helps, as I am thinking of a couple slight changes & moving the piers slightly to better center the Truss span. I put a shot of the whole thing in WPF if you was to see the entire unit..
These appear to be all cut stone, built in the 1850s, I believe.
I can't imagine that they'd bother to face a concrete pier with stone.
This one looks to be a combination of stone and concrete: quite possibly a rehabilitation of an earlier span:
And some of the piers not visible in the second photo:
This is part of the east abutment - note the ironwork tying the stone together.
Wayne
Thanks Wayne, those are interesting pix & designs!
Chad, you do bring up a good point. I do agree w/ Wayne that why veneer a conc pier ( I have seen this for historical reconstruction though). Any concrete "capping" you may see is most likely done to repair "cap" a stone structure or to fit new bridge or shoes.
I notice that the girder/ shoe size requires differing elevations of the pier top. In the process of detailing the pier tops you should consider a shelf for the lower set of shoes. I don't believe that the main span would have been "blocked" up on stone as in the sample pic.
I never did give much thought as to the real detail of the tops on the stone piers I have made. This one was built up Hydrocal "stone" strips glued to a tapered wood block. I was luck enough on this one that the CV truiss and CV girder worked out to a flat top.
This span was to show differing abutments and pier to represent reconstruction of the "new" main line. I still may consider showing remnants of the old crumbling stone abutments.
Modeling B&O- Chessie Bob K. www.ssmrc.org
Thanks Bob,
You have a nice setup there, nice looking bridge set.
I have seen the girder types notched into the piers, while doing my own research, & I like those too.
Unfortunately I have been working on mine & it is built up now with new cast & trued parts.
I guess I have to put artistic license on it..
From my experience working on heritage buildings restoration, I would say that in the old times, most of the time, the exterior was made of cut stone for a better look, more durability and the interior was made out of mortar and rubbles and rough stones. That's the typical way to build in stone. The "veneer" stone acts has a weather protection. Is is often made out of granit or some other durable stone.
A stone structure like a wall and a pier is habitually topped with a stone crowning that acts as a protection from rain. It is slightly slopped for that purpose. Most of the time, they looks like large tiles. That was common practices. I just checked the book "Au rythme du train", documenting many railroad companies in Province of Quebec from the mid-1800 to the mid-1950. Most stone piers are done as I described. Major structure like Quebec Bridge and other cantilevers are also done the same way. I found a nice picture of an Intercolonial bridge commissionned by Sir Sandford Fleming under construction in the 1870's whre you can see clearly the masonny under building.
When concrete became more widespread after 1910, often, stone crownings were replaced by a concrete slab. As stated by Wayne, many piers also received a new concrete base to protect the pier itselft from the elements and erosion. In my area, most bridges date back to 1888-1889 and they received a concrete topping over the years.
Hope this may help you.
@Chad, your scribing is nicely done, however, in real life, that would mean the masonry core is exposed to water infiltration. In only a few years, this pier would be badly damaged and probably would crumble if not repaired and protected correctly. However, as said, the artistic license is fine with me on a layout! If you didn't ask, I doubt many people would have thought about it! ;-) If your nice bridge isn't installed yet, you could easily add a new scratchbuilt stone course to represent the crowning. You could also decide to make it looks like concrete. Large bridges as your had often more elaborate stone work than smaller structures.
@ Wayne: Interesting picture with the iron clamps. Looks like the stone veneer was separating from the core. Probably after water infiltrated and froze. It happens all the time. I've often seen iron sling circling a part (just like a water tank), but rarely seen that. I guess they couldn't rebuild the stone veneer without risking the structure stability. However, I'm not sure about this solution over the long term. If the rods rust badly, they could expand and break the stones. I guess they drilled the only keeping that in mind and with enough space to allow that.
These pillars are located about 300ft from my house, they belong to a "modern" iron suspension bridge (one of the earliest) over the Montmorency falls that collapsed few days after its completion in 1856. You can clearly see the very elaborate crownings. Despite the bridge failure, these pillars are still in great shape today (the inquiry proved they were excellent and should last at least a hundred year, the wire anchors were at fault).
Quebec Bridge piers with their original crowning (still in place and restored by my boss few years ago). Probably one of the most imposing railroad bridge in North American, it never saw the traffic it was supposed to carry (Double main line + 1 tramway track).
The first Quebec Bridge pier, built circa 1906. Infamous botched design by Phoenix Bridge, N.Y. that srastically changed the engineer profession (they designed the structure, then modified the structure to beat the world record, then the client asked to cut cost in half which was achieve by reducing the steel weight by half... Big deal! They never verified the structural strength after all theses modifications and it collapsed miserably in the river). More infos http://en.wikipedia.org/wiki/Quebec_Bridge
Matt
Proudly modelling the Quebec Railway Light & Power Co since 1997.
http://www.hedley-junction.blogspot.com
http://www.harlem-station.blogspot.com
Matt,
Thanks for your response & the great info! It is very helpfull. As my bridge stonework would probably be post 1900, I would guess the piers would have the outside structure act as a form for the concrete & rubble fill in the centers as you described.
Thank you! And thanks to everyone who replied, I enjoy the comments & learning about it!
ChadLRyan Matt, Thanks for your response & the great info! It is very helpfull. As my bridge stonework would probably be post 1900, I would guess the piers would have the outside structure act as a form for the concrete & rubble fill in the centers as you described. Thank you! And thanks to everyone who replied, I enjoy the comments & learning about it!
Chad, I found out this picture in my archives. It's a pair of bridge abutments I made out of styrene and balsa. They follow a prototype built around 1900 located in my area. You can see the upgraded concrete top. Also, the stones at the base are larger to prevent damages (water, erosion, ice, etc.).
Thank you, Matt,
Some more good informaton to work with!
After a bit of thought, & time to evaluate my build, I have been considering building an 0.100"ish top on the piers of my bridge. I thought that following the advise of ya all, & the common practice, it would seem appropriate to do so, so that is my next plan. It also will nest my short cut risers (which may be considered wrong) in a convienient & acceptable way.
I appreciate your thoughts & suggestons, & say a big Thank You!