Bridge project

[MikeD74T]

A few years ago I built a 24' bridge across the stream at my camp. I have pictures of the construction but not digital. Two years ago the planks needed replacement & wanted longer life, so decided to roof the bridge. Also have those pics, non-digital. Last weekend I borrowed a camera & took pics of the finished (almost) project. It's about 5' to the water in the pics and have had 16" of water over the deck on at least 2 occasions. This brook will increase in depth by over 2' in less than 3 hours after a big rain in the nearby mountains.

The original had log railings mounted directly on the deck. Had to add outriggers to attach the 6x6 posts to support the roof and allow for future plank replacements. The abutments are logs but will be replaced by concrete in my retirement years, hopefully in a couple of years.

 

[bones1]

Looks like a big project.What did you use to span the 24'.Are they 1 piece.

 

[wilkesland]

Man that's a nice bridge!

Great job!

 

[firemanpat2910]

I helped build a bridge last year that is 20' long. we had block 12"x12" block walls built. then used 4 20' H beams for the span. covered with RR cross ties 11' milled down to 3" thick. we welded some flat stock to the sides of the outer beams to bolt the planks to. We ended up using carriage bolts but did try some self taping screws that went right into the beam with no pilot hole. These screws were awesome, but they were expensive, were too small diameter and had "hex" heads that would have been on top of the wood.We did not want to have to counter sink them. We spaced the inner 2 beams centered with the wheel span of passenger car & truck tires and the outer beams were centered on th width of my firetrucks. We figured that would be one of the heaviest things to have to cross it. There is an old thread on here that really helped me alot. It was called " build a bridge and get over it" and I can not remember the mans name but it has great pictures and ideas I will try and search and find a link. The mans name was MRHURT. the year was 2004. It was this thread that first lead me to TBN.

 

[schmism]

looks like it would have served you well to raise it up another foot or 2. and just build up some dirt leading to the bridge...

looks like a fun project with a good size creek!

 

[MikeD74T]

bones1 The 4 beams are 14" with a 6" flange, don't know thw weight per foot. Two are spaced 16" apart on center & the pairs were spaced for my Ford 801 wheels. I got them from a steel company that also sells used. Their engineer spec'd the bridge for an 8000 pound live load & this is what they had that was used. Used was about 1/2 price of new. There are 2 sets of 10" spacer beams between the main beams. Planks are bolted w/carrige bolts.

Schmism I'll raise the bridge about 12" when I concrete the abutments. They will be part of a low head hydro dam that will be just upstream. Both times water came over the deck were considered 100 year floods - just 2 years apart. Previous was about 1955. Will put vertical board sides on at that time. Am afraid that solid sides now could push the bridge downstream to it's demise.