I have a 12 foot span. I need to build a bridge across it. This bridge must be able to support a farm tractor.
2006-12-23 12:09:44 · 9 answers · asked by imanucklehed 2 in Science & Mathematics ➔ Engineering
One 6 x 6 will support 620# at the middle. I like the 10 member design above.
This assumes (Southern Pine) Fv = 110 psi, Fb = 1,650 psi, Actual size = 5.5" x 5.5", 4,000 lb tractor.
I would recommend two 8 x 14's if you want a two beam system.
Make sure to provide proper anchorage, especially lateral, and bearing area.
2006-12-24 07:49:23 · answer #1 · answered by daedgewood 4 · 0⤊ 0⤋
If you use about 10 of them (@ 16ft, not 12ft; 2ft in the ground at either end) along the span and then use smaller ones to go across the width, bolted to the beams and acting as a platform it should hold.
Use pillars at every 4 feet on each beam that are dug into the ground and anchored with concrete.
A bridge like that could hold more than a tractor.
2006-12-23 12:40:29 · answer #2 · answered by Johnny 2 · 1⤊ 0⤋
It depends if you are using it as a column (vertical) or as a beam (horizontal). A 4x4 column is a lot stronger than a 4x4 beam. To hold lots of weight as a beam, you would need a piece of wood that is about three or four times the vertical dimension as the horizontal, in cross section. (For example, a 2x6, or a 2x8). Contact an experienced carpenter for help!!
2016-03-13 21:42:04 · answer #3 · answered by Anonymous · 0⤊ 0⤋
24
2006-12-23 12:12:24 · answer #4 · answered by Princess1988 1 · 0⤊ 1⤋
1
2017-01-25 14:19:15 · answer #5 · answered by Anonymous · 0⤊ 0⤋
If you are planning to start on your woodworking project, this isn't something you should use, it's something that you would be insane not to. Go here https://tr.im/T0OSg
Truth is, I've been a carpenter for almost 36 years, and I haven't found anything like this for less than 10's of thousands of dollars.
2016-05-01 20:17:17 · answer #6 · answered by son 3 · 0⤊ 0⤋
6x6x12 Treated Post
2017-01-16 11:58:16 · answer #7 · answered by ? 4 · 0⤊ 0⤋
Not enough, you can probably just put some supports in though. Google images will have tons of pictures of bridges if you need ideas on how to do that.
2006-12-23 12:13:28 · answer #8 · answered by NeRdYkId1101 3 · 0⤊ 0⤋
you didnt give the weight of the farm tractor. considering the span of 12 feet i would say no.
2006-12-23 12:14:47 · answer #9 · answered by i_b_peein 2 · 0⤊ 0⤋
try putting the brodge on the ground.
2006-12-23 13:15:42 · answer #10 · answered by bunywars5000 3 · 0⤊ 1⤋