does anyone know anything about building bridges? Got a call today to perhaps replace one. Private residence, preformed concrete, approximately 25 feet long (two lane) by 15 feet wide (span distance). Apparently washed out/ got undermined from the storm Sunday.
Start your environmental impact survey tomorrow and apply for a Corps of Engineers permit. In about ten years you may get approved to start construction, unless there are court challenges from the neighbors. Just kidding, but I'd be surprised if you didn't need some permits to proceed from somebody.
John. Do they intend replacing with concrete?. We have built stone arch bridges, fun, hardwork, and expensive...but well worth it.
Surfer - you're right, we're going to look into the wetlands, zoning, engineering, etc. issues. Squizzy - yes, nothing architectural or fancy, just a plain-jane concrete/steel bridge that functions as such.
I've built a few. I'm a little dense. Is it 25' wide or is the span 25'? The length of the bridge is from bulkhead to bulkhead. I'm not an engineer though, I just do what the plans say.
We built one for access to our shale/topsoil pit. There was a old existing wooden bridge and we built a concrete one on top of the old one. We poured a 12" thick by 3' wide footer and built headwalls and placed the headwalls on the footer. The head walls are 2' x 2' and we placed (4) 24" beams on the head walls and then poured 13" of concrete on top. All concrete was 4,000 psi air entrained and contained 3/4" rebar. In the pics, you see that we placed 10" beams on the sides and welded t-rail to them to hold our concrete forms. Also, this is a 40' span bridge.
BTW......if anybody says that old wooden bridge isn't safe. It has been there since the 70's and I took our 955 across it.
John, Not sure if this would work in your situation or not. Might be worth a look. http://www.baileybridge.com/index.html
Hey John Need more info...how high, how much water, etc. Can you get a picture? Could you just replace with large pipe or box culvert?
Heres a site with some good basic info on bridges. http://www.brantacan.co.uk/bridges.htm another http://www.brantacan.co.uk/bridgeother.htm
John- i'm a little baised here, but check out Texas DOT website at www.dot.state.tx.us should be able to access online bridge design guides. Many, many bridges built in the Lone Star State using standard precast concrete panels, prestressed concrete beams. Pretty boilerplate design standards....
Here's the bridge I built to cross the stream in my driveway. The neighbor down steram put in 3 sets of pipes in the 10 years that I owned the property before I started construction so I went with concrete and steel. No problems in 17 years.
The deck is a 40' flatbed trailer that was junked due to a broken gooseneck. I sectioned out the broken section and made it match the rest of the beam. I cut the trailer in half and set the two pieces side by side for a 15 x 20 deck. I put rough sawn oak down for the deck, crossmembers are on 12" centers. The oak only lasted about 7 years before it rotted so I replaced it with pressure treated 2x. I've had a 65 ton crane across this bridge as well as tri-axle dumps loaded with 22 yards of material.
The key to building a solid bridge is making the abutments long enough so there is no possibility of water getting behind them during flooding. This stream has risen to the point that the water has touched the bottoms of the guard rail posts during floods. Also make provision for water that will run on the pavement so that it doesn't wash material from the sides of the bridge. I put a catch basin on the high side to catch the water running down the driveway and guide it to the stream
Thank you fellas, I appreciate all the info. The pics are great. I'll take a look at the links too. Again, thank you.
I don't know Steve, I've driven across your bridge a couple of times and it felt a little rickity