Guest cbrunberg Posted March 22, 2004 Share Posted March 22, 2004 Hey guys, I need to build a short bridge (24 feet) on my property. I don't have access to steel tables (charts). My father, a civil engineer has recently taken ill and is permanently hospitalized. I don't need anybody to sign off on anything only a table yeild specifcation. If anybody has access please e-mail me. Thanks Carl Quote Link to comment Share on other sites More sharing options...
Guest Phil1934 Posted March 22, 2004 Share Posted March 22, 2004 How far is the nearest precast yard? Two double tees would do it and you would get the deck also. Questions others will ask. Will this bridge be required to support fire truck loading or is there other access to the house? Quote Link to comment Share on other sites More sharing options...
Guest cbrunberg Posted March 22, 2004 Share Posted March 22, 2004 This is the only access to the house. I'm designing for 60,000 lbs. A cement mixer. The span is 24 feet, the depth is only 3 feet. The banks are not steep (about 25 deg.) The base is crushed rock with 30 years daily driving in and out. There has been regular crossings with dump truck and back hoe and occaisional crossing by the propane delivery truck. The problem is that my Z car is too low to cross and friends and family with nice cars won't come visit. The local Gov. won't allow a culvert and gravel without several thousand $$ of studies and reports by various agencies, It's California. They will allow a span that doesn't infere or touch the bottom. The precast was a thought but is logistically difficult. I'm in the mountains on a narrow twisty road and no place to stage heavy vehicles while working. My idea was to build a steel deck with a welded grate top (to prevent lift if the water comes over the top). There's not enough flow to worry about a tree snagging it. My concept: 2- 24 foot by 12 inch wide flange beems parallel 10 feet on center. With 2-24 foot by 8 inch beems running parallel 6 feet on center and centerline between the 12 inch beems. Perpendicular between the 12 inch units and under the 8 inch units are 4 inch channels approx 10 feet long. The driving surface would be heavy expnded metal grate (like is used for equipment ramps). The ends would be welded to 12 channels and anchored to poured in place footings. That's the ruff idea. Sizing the steel was my next step... Quote Link to comment Share on other sites More sharing options...
Guest cbrunberg Posted March 22, 2004 Share Posted March 22, 2004 Sorry! My spelling isn't great. Beams not beems. CB Quote Link to comment Share on other sites More sharing options...
dmyntti Posted March 22, 2004 Share Posted March 22, 2004 A buddy of mine put in a similiar bridge. What he did was find someone selling a flat bed semi trailer. He bought the trailer without the axles and the person we bought it from delivered it and removed the axles. All he needed to do was cut off the front (headache rack) and build small ramps on and off of the bridge. Just a thought. Sorry I do not have my engineering tables handy. Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted March 22, 2004 Share Posted March 22, 2004 http://www.eurekalert.org/pub_releases/2002-09/jhu-fsp090302.php http://www.sciencedaily.com/releases/2002/09/020904073045.htm http://home.coqui.net/jencinas/Steel-bm.htm http://www.centralsteel.com/struct.htm Quote Link to comment Share on other sites More sharing options...
SHO-Z Posted March 22, 2004 Share Posted March 22, 2004 I did a quick look W12x63 or W12x 58 should work using the beam size program that I have. I am a mechanical engineer and do not design bridges. Quote Link to comment Share on other sites More sharing options...
Guest cbrunberg Posted March 22, 2004 Share Posted March 22, 2004 Thanks guys, Grumpy, as always a wealth of info links. I used one of the programs you provided and came back with same simple calc as SHO-Z Once again you guys are the best. PS dmyntti I was looking at useing a trailer but for the price of the trailer and delivery I could build new. Also trailers are 8' - 8'-6" wide. I perfer at least 10' wide the extra really helps when towing a trailer and making the turn just before and after the bridge. Quote Link to comment Share on other sites More sharing options...
Chaparral2f Posted March 23, 2004 Share Posted March 23, 2004 Have you given any thought about using a railroad flatcar? I have seen bunches of them used for bridges on local ranches, and they seem hell for strength, althoutgh the length is a problem I guess. Quote Link to comment Share on other sites More sharing options...
Guest cbrunberg Posted March 25, 2004 Share Posted March 25, 2004 Yah, I thought about it but I don't know where I'd get one or how I would handle it or what one might cost plus delivery. What ever I do it better be soon. Steel prices are going through the roof. I bought 2' comduit 2 weeks ago for $7.54 per 10 foot piece. That same piece was $15.54 today. Plywood, steel, gas it's all going throught the roof. So much for flat inflation. I got a quote from my local steel vendor and he's not happy. my cost for new steel is .40 per pound but he warned me it will probably go up 25% or more in a couple of weeks. It's something to do with the Chinese buying up all the scap and cornering the market. They overpaid for the scrap and got everyones business. Now they can control the retail. Something like that.... Carl Quote Link to comment Share on other sites More sharing options...
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