[homeboy]

20 years ago my municipality did a beautiful restoration on a historic 113 year old railway station in our town. It has a large pine board loading deck area totaling roughly 60ft long x 12ft with some angles and bays in the mix. It is supported by a tubular mild steel frame on concrete supports. As this is a busy public place used for many functions, in the winter a lot of salt has been used and the steel frame has deteriorated very badly and has to be replaced. I am involved in the reconstruction planing and am looking for information on the best materials and methods to make sure that this repair is done right and lasts for a long, long time. One thought being tossed around is to prefabricate a bolted support structure out of open structural steel,( not enclosed tubing as built), C channel, I beam etc. and have it all hot dip galvanized. Due to some of the irregular shapes it would have to fit around that could be a bit of a challenge as it all has to be fabricated before hand. Another is to use stainless steel members and field cut, fit and weld on site to match the building profile exactly like it was done the first time. There are 3 access doors along the length of the deck and we need to work in stages to keep the station open as much as possible. Logistics!! Once a material and method is chosen there will be some engineering involved. Does stainless make sense, what grade and so on? Cost of course is a factor but the primary objective is to get it right!

[Bill Beauregard]

Done right stainless lasts forever.It WON"T be cheap!!!!!!!!! Hot dipped galvanized, I'll show you my trailer. The entire structure changes its shape when dipped.
Aluminum will last forever, needs no treatment, and could be built in place.

[homeboy]

Done right stainless lasts forever.It WON"T be cheap!!!!!!!!! Hot dipped galvanized, I'll show you my trailer. The entire structure changes its shape when dipped.
Aluminum will last forever, needs no treatment, and could be built in place.

Thanks for the info. At this point I haven't got into pricing, just finding relevant options and going from there. Personally I know the built in place option is the only one that makes sense in this case but I need to gather enough relevant info and estimates to present a report to convince the committee. Glad you mentioned about the hot dipped galvanized vs trailer frame as I have been thinking of having one done sometime but might rethink.

[Poland308]

Aluminum doesn’t like the salts used in ice melt.

[Arno]

Left-field idea.. Does it have to be a full metal (sub)frame under the deck?

Aka. Would a wood/lumber structure work too? No idea of the expected loads, but as it's described as having a wooden deck I suspect it's not meant to drive vehicles up onto and such..

If built well and if the feet are designed properly to keep the moisture out (and rot away) then it would last a loooong time and be pretty much impervious to salt and the like.

Yeah.. I know this isn't a wood-working forum, but just to make sure we're not in the "if you have a hammer then every problem looks like a nail" mindset

Bye, Arno.

[homeboy]

Left-field idea.. Does it have to be a full metal (sub)frame under the deck?

Aka. Would a wood/lumber structure work too? No idea of the expected loads, but as it's described as having a wooden deck I suspect it's not meant to drive vehicles up onto and such..

If built well and if the feet are designed properly to keep the moisture out (and rot away) then it would last a loooong time and be pretty much impervious to salt and the like.

Yeah.. I know this isn't a wood-working forum, but just to make sure we're not in the "if you have a hammer then every problem looks like a nail" mindset

Bye, Arno.

Aluminum doesn’t like the salts used in ice melt.

The salt issue is something I have concerns about and have been trying get some info on. I have no knowledge of metalergy and that's why I am looking for info on best material / grade etc. I already had the conversation about making sure de-icers are compatible with whatever material we decide on. Arno -- Not left field at all. I have looked a bit at structural treated wood timbers just see whats available and it could well be considered. There are many very old treated timber structures ( railroad / marine etc ) that have certainly proved the test of time.This is all at a preliminary stage to get enough info to be able to start narrowing things down to the final " hopefully right" solution.

[Bill Beauregard]

Done right stainless lasts forever.It WON"T be cheap!!!!!!!!! Hot dipped galvanized, I'll show you my trailer. The entire structure changes its shape when dipped.
Aluminum will last forever, needs no treatment, and could be built in place.

Thanks for the info. At this point I haven't got into pricing, just finding relevant options and going from there. Personally I know the built in place option is the only one that makes sense in this case but I need to gather enough relevant info and estimates to present a report to convince the committee. Glad you mentioned about the hot dipped galvanized vs trailer frame as I have been thinking of having one done sometime but might rethink.

I had a 9 year old trailer rusted to an alarming extent. I wanted a 5 ton deck over. A fellow 60 miles from me was building trailers custom designed to my specifications. I opted for all steel & had it hot dipped in galvanized. The trailer twisted. Sitting on the level, one rear corner was six inches higher than the other. Had to take it to a frame shop and have it straightened.

[cj737]

Aluminum doesn’t like the salts used in ice melt.

Say it again. It doesn't even like saltwater much for very long.

[homeboy]

Done right stainless lasts forever.It WON"T be cheap!!!!!!!!! Hot dipped galvanized, I'll show you my trailer. The entire structure changes its shape when dipped.
Aluminum will last forever, needs no treatment, and could be built in place.

Thanks for the info. At this point I haven't got into pricing, just finding relevant options and going from there. Personally I know the built in place option is the only one that makes sense in this case but I need to gather enough relevant info and estimates to present a report to convince the committee. Glad you mentioned about the hot dipped galvanized vs trailer frame as I have been thinking of having one done sometime but might rethink.

I had a 9 year old trailer rusted to an alarming extent. I wanted a 5 ton deck over. A fellow 60 miles from me was building trailers custom designed to my specifications. I opted for all steel & had it hot dipped in galvanized. The trailer twisted. Sitting on the level, one rear corner was six inches higher than the other. Had to take it to a frame shop and have it straightened.

I would freak !! When I build the frame it's dead level on threaded, height adjustable stands, X string corner / corner method, max 1/16in deviation all dimensions. Researched the prep required to the frame to allow proper galvanizing coverage ( I use a lot of tubing ) and ensuring nothing exploded! Really wasn't a "need" just something different. Primer and Tremclad looking better all the time! Couple years ago I scrapped a snowmobile trailer my brother and I built in the late 70's. Tubing and Tremclad. Fixable but getting tough. Not bad.

[homeboy]

Aluminum doesn’t like the salts used in ice melt.

Say it again. It doesn't even like saltwater much for very long.

Been doing some reading on aluminum just to get a bit more understanding and see chlorides are an issue. Only ever worked with mild steel so I have a bit of understanding there but other metals not so much. Highly likely a timber frame will make the cut but it's a "committee decision" so i need to be prepared to make my case. As a fairly new member of a municipal council and the only member of council or staff that has real construction experience ( lifetime) I am attempting to put this together in the most cost effective way possible. Knee jerk reaction in the past has often been to spend big bucks on lots of professionals even for a job like this that's relatively simple with a bit of research. My time is free! Appreciate the help.

[Simclardy]

Do you have any photos? I like the wood idea. If you can get black locust it should last 80yrs in contact with soil. I believe the Brooklyn zoo just built a bridge with black locust. My next thought would be heavy duty steel and paint. Many old bridges are in the salt environment, im thinking of the 2 bridges over the cape cod canal near my home. I would keep the steel out of the dirt obviously. Some type of concrete pier. You don't want water splashing on the steel if possible.
Stainless steel will be very expensive. You would save on maintenance cost but i don't think the council will like the price.
Cheers

Sent from my SM-G930V using Tapatalk

[homeboy]

Do you have any photos? I like the wood idea. If you can get black locust it should last 80yrs in contact with soil. I believe the Brooklyn zoo just built a bridge with black locust. My next thought would be heavy duty steel and paint. Many old bridges are in the salt environment, im thinking of the 2 bridges over the cape cod canal near my home. I would keep the steel out of the dirt obviously. Some type of concrete pier. You don't want water splashing on the steel if possible.
Stainless steel will be very expensive. You would save on maintenance cost but i don't think the council will like the price.
Cheers

Sent from my SM-G930V using Tapatalk

I don't have any photos yet but may later. I looked up the Black Locust which sounds interesting and it could be a possible contender if available. We have one very old riveted, I am guessing iron, bridge that doesn't seem to rust out like I would expect regular steel to. Maybe someone can explain why?

[homeboy]

Do you have any photos? I like the wood idea. If you can get black locust it should last 80yrs in contact with soil. I believe the Brooklyn zoo just built a bridge with black locust. My next thought would be heavy duty steel and paint. Many old bridges are in the salt environment, im thinking of the 2 bridges over the cape cod canal near my home. I would keep the steel out of the dirt obviously. Some type of concrete pier. You don't want water splashing on the steel if possible.
Stainless steel will be very expensive. You would save on maintenance cost but i don't think the council will like the price.
Cheers

Sent from my SM-G930V using Tapatalk

I don't have any photos yet but may later. I looked up the Black Locust which sounds interesting and it could be a possible contender if available. We have one very old riveted, I am guessing iron, bridge that doesn't seem to rust out like I would expect regular steel to. Maybe someone can explain why?

[Arno]

We have one very old riveted, I am guessing iron, bridge that doesn't seem to rust out like I would expect regular steel to. Maybe someone can explain why?

If it's old-skool (hot-)riveted then the bridge is likely either made from a ductile cast-iron or wrought-iron.

Both are much slower corroding than mild steel as they do not form the flaking rust layers that pit and dig into the material and the (usually fairly thin) outer corrosion layer slows the rate of further corrosion. (usually from the silicates in the material)

Similar effect you can usually see on old industrial machinery that has been left to rot outside. Any cast-iron or wrought-iron bases and other parts usually stand up well to the elements, anything steel that was attached to it like blades or tooling usually rusts/pits away to nothing in a few years.

Bye, Arno.

[homeboy]

We have one very old riveted, I am guessing iron, bridge that doesn't seem to rust out like I would expect regular steel to. Maybe someone can explain why?

If it's old-skool (hot-)riveted then the bridge is likely either made from a ductile cast-iron or wrought-iron.

Both are much slower corroding than mild steel as they do not form the flaking rust layers that pit and dig into the material and the (usually fairly thin) outer corrosion layer slows the rate of further corrosion. (usually from the silicates in the material)

Similar effect you can usually see on old industrial machinery that has been left to rot outside. Any cast-iron or wrought-iron bases and other parts usually stand up well to the elements, anything steel that was attached to it like blades or tooling usually rusts/pits away to nothing in a few years.

Bye, Arno.

A good example of this is - Blackfriars St bridge in London ON CA. Wrought iron, unique design, built 1875, complete restoration last year, in use today. Unlikely we'll get that kind of life from our train station deck project. Never know!