I need to build a bridge to open up a pasture. It was be traveled by horses and people. I am thinking of three ways to go about it. 4 concrete footers (2 on each side of the stream), 2 6x6s and several 2x6 for the slats. Or, the same thing but instead of the 6x6s, use steel i bars. And finally, find a culvert and have it put in as the final thought.To give you more information on the setting, the span is about 10 feet long and I would only need it to be about 6 foot wide for this purpose. The water does get pretty high during heavy rain, but never exceeds the banks, even during major floods. Most of the time it is a trickle. Banks are around 4 foot high. I have no idea where I can get i beams or culverts big enough for this gap. Also, not sure what the best method is. Would like to avoid culvert because I would have to contact the township and hire an excavator. A bridge I can most likely do myself.Any ideas are GREATLY appreciated!!
google how to make a bridge
consider a junk yard flat bed off a truck. i have the i beam style and it moves no matter how hard i concrete it in and down.
I think your first idea is the best one, but I would say to use 6 concrete supports ( three on each side adding a middle support) because you don't want to have a 6' span of 2X6 material. Take a 1000 pound horse or more than one and you may have a board break as it ages, not to mention that the 2X6's will warp down with moisture and time. So build the supports with 12 concrete tubes, for the frame from side to side I would use a double 2X10 instead of a single 6X6 for the 3 beams you would build, and then either 2X6 or 2X8 on the flat for the deck of your bridge. Considering the water exposure you should use stainless steel screws to join the deck boards down to the frame and TimberLok screws for the framing.
Cross-Ties,..like on a Railroad track makes a good bridge...Place 2-3 Ties at the point that would support the weight of a Truck or tractor....(4 or 6 total) The Bridge has to be secured to the ground, otherwise it will Float Away,..Ah Ha ha(trial and error) If you intend to have children riding horses, and crossing.. A culvert covered with gravel, would make more sense,..Not all Horses will readily cross wooden bridges.. If you know of Iron scrapyard,..They would have big size pipe(Oil-field,Casing, Drive-pipe).. The culvert would last the longest.. 2X6's as deck is not strong enough,..and it's possible a horse could step thru in a defect or rotten stop.. Old Time County bridges were deck with 3x 12,..at right angle to the sills,..then another set of 3x 12 run catter-corner,..at right-angle for strength....
