Need Bridge (deck) input

North Idaho Wolfman

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Does this help clarify it?
So very similar to GSD- Keegan

Putting 2x's standing up and putting a deck over that will do nothing for support.

20230613_195709.jpg
 
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GrizBota

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Sure, give me the 40,000 i was quoted for a culvert and I'll be glad to pay a professional to do it.

btw, lot next door had a house that was just completed. They paid 50,000 for their fire marshal approved / engineered culvert and got a discount because they heavy equipment was there already to clear the land and dig the basement to build the house.

Dan
$40k for a 20 ft stick of 24 inch HDPE culvert with three feet of fill is great, for the contractor. Seriously that’s about a a $10k job all day long in my field. That includes the fill and compacting it and probably a six inch thick gravel surface.

20 ft of 24” culvert at $250ft, installed.
60 cy of fill, 7 ea 10 yd truck loads at $300 each
Equipment (exc, loader, dozer, only need one), one 8 hour day at $300/hr (w/ operator)
20 tons of gravel (one 10 yd truck load) at $35/cy, placed.

Did your contractor give you anything remotely like that? Or are you looking at a six ft diameter culvert?

But, bridges are cooler.

I see we have more bridge engineers on this site than I would have thought.

Anyhow, you really need to be thinking about connection details, how to connect beams to the foundations and the deck to the beams. You plan of 2x8 or 2x10 will get you there. But think about how to secure the 2x to the beams. Also, you’ve got a vertical grade issue on the low end, I’d try to do that with all little fill as possible.

The idea of transverse steel members to keep the beams parallel is good, as is the high/low vertical staggering of those members. Connecting the beams I in the middle is not great and connecting with anything other than welding or structural gusset plates and structural bolts is not good. I kind of like the railroad tie decking idea, hell for stout. Here in the PNW the cheap used ties are $25 each. You’d have to think on connection details again.

BTW the least expensive, simplest highway bridge over here is roughly $300/s.f. of deck surface area out the door. But obviously built much differently than what you’ve got going on.
 
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forceten

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I just put in 70 feet of 24" culvert. Started with 10 feet but liked it so much did 60 more feet. Three 20 foot sections and one 10 foot. Even did a flare at the start and a cage to stop branches from going in

I already had equipment - kx080 excavator, 6060 and bx25. But it can be done without much equipment. Just harder to slide the pipes together.

20' sections of 24" was about $600 a pop. Flare was stupidly priced at $450 but I still bought it. Cage was $300. I already had lots of fill dirt but if I thought about it maybe 60 tons of fill dirt and maybe 40 tons of crushed rock on top.

I think if I had to buy the dirt would be about $1,000 for the dirt, $600 for the crushed rock and $2850 for pipes and end.

Oh and rip rap for stop the new berm from eroding maybe 3 tons $150
So about $3600 for me as I had dirt. I could drive a tank over it no problem

If you only need to do a 10 foot or 20 foot section you are $600 for the pipe - dont have to do a flare end cage really. Dirt and rock should be under 1K

So for about $1500 maybe $1600 with rip rap you will have a bridge that wont rot and is strong as hell
 

dan_m

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Does this help clarify it?
So very similar to GSD- Keegan

Putting 2x's standing up and putting a deck over that will do nothing for support.

View attachment 104919
The 2-3" boards you're referring to are real 2" or 3" thick and not nominal? The Reason I was using the 2x8" standing up was to support the weight as what I found is 1.5" thick board was not enough to support the weight I have in mind across the span between steel beams.

I found a few more local hobby type saw mills last night that I will get quotes for boards in the next few days.

Dan
 

dan_m

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$40k for a 20 ft stick of 24 inch HDPE culvert with three feet of fill is great, for the contractor. Seriously that’s about a a $10k job all day long in my field. That includes the fill and compacting it and probably a six inch thick gravel surface.

20 ft of 24” culvert at $250ft, installed.
60 cy of fill, 7 ea 10 yd truck loads at $300 each
Equipment (exc, loader, dozer, only need one), one 8 hour day at $300/hr (w/ operator)
20 tons of gravel (one 10 yd truck load) at $35/cy, placed.

Did your contractor give you anything remotely like that? Or are you looking at a six ft diameter culvert?

But, bridges are cooler.

I see we have more bridge engineers on this site than I would have thought.

Anyhow, you really need to be thinking about connection details, how to connect beams to the foundations and the deck to the beams. You plan of 2x8 or 2x10 will get you there. But think about how to secure the 2x to the beams. Also, you’ve got a vertical grade issue on the low end, I’d try to do that with all little fill as possible.

The idea of transverse steel members to keep the beams parallel is good, as is the high/low vertical staggering of those members. Connecting the beams I in the middle is not great and connecting with anything other than welding or structural gusset plates and structural bolts is not good. I kind of like the railroad tie decking idea, hell for stout. Here in the PNW the cheap used ties are $25 each. You’d have to think on connection details again.

BTW the least expensive, simplest highway bridge over here is roughly $300/s.f. of deck surface area out the door. But obviously built much differently than what you’ve got going on.
Nothing around where I live is cheap in terms of contractors. It was earlier this spring when I got the quote and I think it was using 6' culverts, 2 of them.

I'll try to get a picture of neighbors culvert that he said was 50k. I'm not sure about the company that did his though, when site work started the operator drove the dozer through the creek at least a dozen times on the first day when I was at work . No culvert, no silt fence, just driving through the creek. After a call from my downstream neighbor that earned them a 5 day stop work order from the county.

Dan
 
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fried1765

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I was once metal detecting under a bridge very similar to yours, about the same size, and same type I-beams.
They had placed 3 or 4 heavy wall pipes, maybe 4"-5" in diameter, between the I-beams, and drilled holes in the webs for some large threaded rod. They clamped the pipes between the I-beam webs with the threaded rod, and then welded the pipes in place.
The "deck" was rough sawn lumber, (oak?) probably 3"x 10", bolted to the beams with carriage bolts.
Looked like it had been there for 20 or 30 years.
A very satisfactory, simple, and cost effective solution !

Having a CE degree.....once upon a time long..long ago,..... I did some rudimentary bridge design.
With all due respect, it does appear to me that the OP is in this project way over his head.
 
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GrizBota

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Nothing around where I live is cheap in terms of contractors. It was earlier this spring when I got the quote and I think it was using 6' culverts, 2 of them.

I'll try to get a picture of neighbors culvert that he said was 50k. I'm not sure about the company that did his though, when site work started the operator drove the dozer through the creek at least a dozen times on the first day when I was at work . No culvert, no silt fence, just driving through the creek. After a call from my downstream neighbor that earned them a 5 day stop work order from the county.

Dan
Well a six ft culvert is going to run you quite a bit more. $40k might not be too wild.
 
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dan_m

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Well a six ft culvert is going to run you quite a bit more. $40k might not be too wild.
It have just been one, I don't recall and I can't find the quote - It probably wound up in the trash.

Even dirt is expensive, local places close to me are 30+ a yard (unfiltered) and smaller delivery fees. Cheaper places are 20-25, but those places are further away (2 hour round trip drive) and charge a fat fee for delivery.

I have some low areas I'd like to level out in my yard. After getting bridge done, will be taking some dirt from across woods to use when I level a few driving paths.

The new neighbor who had the house built next door said another neighbor and I could have some of their dirt they were going to remove for free. The one neighbor has access to dump trailer and offered to haul it so there was no cost for dump truck driver (he's 3 houses down, I'm next door). However, the building contractor used it for other home sites he had in the works. They moved at least 50 dump truck loads of it. Then after house was done and they were doing landscaping, brought 5-10 loads back.

There are still a number of neighborhoods not far from me being developed after calling a few of them, they dirt is already spoken for.

Right before the pandemic, the friend who gave me the beam was able to get 247 loads (if memory serves) from a neighborhood development and leveled a large area in his back yard. Looking at it today, you couldn't tell it used to be a large hill/ravine.

Dan
 
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dan_m

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A very satisfactory, simple, and cost effective solution !

Having a CE degree.....once upon a time long..long ago,..... I did some rudimentary bridge design.
With all due respect, it does appear to me that the OP is in this project way over his head.
This post has given more different ideas I hadn't considered. Some better, some easier and some more work. As with anything the first time, it's a learning curve and sometimes the information you need isn't easily available.

With time and money, anything is possible. It's about making it work with as little money as possible.

Dan
 
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North Idaho Wolfman

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Normal good quality 2x6's would be fine, would true 2" or 3" be better, yes.
While oak sounds great, but it would require pre drilling all the fastener points.
The boards on the ends under the deck that run parallel to the I beams and a the 45 degree boards add a huge amount of strength to it.
You don't need as many 45 boards as you have deck boards one every 5 or 6 will do it.

Are your I beams bolted to your concrete piers?
If not that's one of the first things that needs to happen.
Should have been poured with cane bolts in them.
You should also have a rubber buffer between the I beam and the concrete.
 
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GrizBota

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Wow, fill dirt being trucked an hour. That would tend to make it very expensive. Thats 2 hours of truck and operator per load. Easy $300 plus the dirt.

Have fun with the bridge project. You’ve got a popular topic and lots of input.
 
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GrizBota

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This post has given more different ideas I hadn't considered. Some better, some easier and some more work. As with anything the first time, it's a learning curve and sometimes the information you need isn't easily available.

With time and money, anything is possible. It's about making it work with as little money as possible.

Dan
That last part is pretty much why the discipline of Engineering (pick a branch if you’d like, Civil in this case) exists. Make the design and construction fit the performance needs (while meeting applicable codes) while being economical and timely. Fancy bean counting.
 
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GSD-Keegan

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I rebuilt my bridge last year, and reused 22 ft 6 inch I beams. The I beams were basically sitting on , and bolted to a concrete pad. I learned the footprint of the pad was not large enough and the pad sank. I was only driving a small riding mower, or atv, or Snowmobiles across the bridge. The bridge lasted 20 yrs with pressure treated 2x6. Same scenario, got my new tractor and wanted to get it across the creek. I poured a larger cement pad, and incorporated a raised section like a curb about a foot tall with rebar and cane bolts. The I beams were spaced so that the tractor wheel stance would be directly over the beams. I do not have any supports between the two I beams to tie them together. Maybe I should have?? But so far so good. And the bridge was almost submerged during the spring melt!

IMG_0407.jpeg
 
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dan_m

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Normal good quality 2x6's would be fine, would true 2" or 3" be better, yes.
While oak sounds great, but it would require pre drilling all the fastener points.
The boards on the ends under the deck that run parallel to the I beams and a the 45 degree boards add a huge amount of strength to it.
You don't need as many 45 boards as you have deck boards one every 5 or 6 will do it.

Are your I beams bolted to your concrete piers?
If not that's one of the first things that needs to happen.
Should have been poured with cane bolts in them.
You should also have a rubber buffer between the I beam and the concrete.
The piers are set using a 24" round sonotube that was 12' long cut into 4 pierce so 3' per pier.
The concrete is 5000psi quikrete with 8 -10 pieces of rebar inside.
The beams are bolted down to concrete piers using concrete anchors (2 per beam per pier) that were set in the concrete before it cured. The concrete piers were completed last fall.

I picked up the anchors, rebar and sonotube from a concrete supplier.

No rubber buffer at this point.

I didn't think 1.5" (2x6, 2x8, etc) laying on side would be sufficient for weight - That's why I was thinking of running them as a joist is done on a deck, then putting a layer of decking across it to be flat and drive/walk on. That's good news.

Still a lot to do that was not mentioned. you can tell in the picture that the far side has square concrete pads under the end of the beam, plan to do same for near side. Also plan to use a rust inhibitor primer on the beams and if using treated wood, will do a water barrier

Based on some feedback here, some things will be tweaked.

Thanks for all the feed back, positive, negative and details to fill in my knowledge gap.

Dan
 

dan_m

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Wow, fill dirt being trucked an hour. That would tend to make it very expensive. Thats 2 hours of truck and operator per load. Easy $300 plus the dirt.

Have fun with the bridge project. You’ve got a popular topic and lots of input.
That's why the dirt project hasn't been done yet and why after completing the bridge, I'll have access to free dirt that will need moved anyway to make some nice levelish paths.

looking forward to access the rest of the property by something other than foot :)

Dan
 
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dan_m

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That last part is pretty much why the discipline of Engineering (pick a branch if you’d like, Civil in this case) exists. Make the design and construction fit the performance needs (while meeting applicable codes) while being economical and timely. Fancy bean counting.
Every profession has fancy bean couting.

When I started this project, I didn't think it would be as difficult as I found out to find the details i was looking for to accomplish what I wanted.

This has been a huge help and wealth of knowledge.

Dan
 
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GreensvilleJay

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I know ,late into this post, but kinda wondering.....
basic info, 1st post ....8' wide by 20 ' long 'bridge'...to drive a BX238 over..

why didn't you just buy a '20' long car hauling trailer, pull to the 'creek, install, then remove the tandem axles.....even a brand new one is less than $5K, well was.....

heck a 20' 'big box delivery van' could give you am 'enclosed' bridge.....

I've known several guys use 48' straight decked trailers as bridges.New ones are arched.....

just curious....
 

GrizBota

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Using a trailer, that’s an interesting idea, especially if it’s less expensive. A concrete slab or a mud sill of railroad ties at each end would probably do it. The way the trailer supports the load is different if the axles are near the center, but it’d probably be fine for reasonable loads.
 

dan_m

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Using a trailer, that’s an interesting idea, especially if it’s less expensive. A concrete slab or a mud sill of railroad ties at each end would probably do it. The way the trailer supports the load is different if the axles are near the center, but it’d probably be fine for reasonable loads.
I consider trailer idea, but didn't want to go that route for a few reasons.

the last few days, I did get the remaining 2 concrete pads for the near side end of the beams poured and beams sprayed with rust inhibitor (jacked up and sprayed under as well) and bolted down to the concrete columns. Also got a few holes drilled - didn't take as long as I thought it would- especially since I was using a 20v dewalt drill with step bit using cutting fluid)

I found a few more localish mills that can do white oak boards - still waiting on quotes from a some.


Dan