Trailer Loading and CQ - Hypothetical Discussion

[Beltzington]

Sodo's drawing is dead-on, he even got the grade right which is impressive considering he has never seen the place. His idea is also exactly how I was originally planning to do it but the more I thunk about it the more I like not having to move large logs, repeat.

Keep in mind there is not an actual hitch on the flat-rack, we have just been using the term to denote which end we are talking about. So my only option is to use my tractors loader. The 10K axle I can buy/build but had not considered the tires sinking in the ground, it will have to be when with dry ground, but this is clay so I believe it will support 5klbs/wheel.

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[schmism]

to complicate things more, remember that you can load the inside (or the top of the trailer) with more weight on the short end so as to balance the long end.

There is an amount of weight that can always be added to the short end that will make the trailer perfectly balance on the single axle such that the amount of tongue load on the loader is a non-concern. (granted this fails as you aproach 0 distance on the one side as the amount of weight becomes unreasonable and at 0 condition you have a divide by 0 condition so.... grain of salt there)

the levers link Levers can be updated if you convert your distributed load into a point load. to do that you take the lenght times magnitude =total force and apply that single force in the center of the distributed load.

for instance, a 10 lb load that runs from 0-6' and a second 30lb load that runs from 6'to 10' can be considered a single 60lb load at 3' and a single 120lb load at 8'

as to your question about do the forces change if you change the angle of the trailer (moving up hill or down) yes. anyone that has ever carried furniture up stairs knows that as you tilt the top up, the bottom guy carries more weight, to the point that its vertical and the bottom guy carries ALL the weight. To calculate this, consider a seasaw that has 2 guys sitting on it without any ground under it. As they tilt the seesaw, the distance between the 2 guys gets shorter (again at vertical they are sitting on top of each other) so at some point inbetween, the effective distance between the weight they are applying and the center piviot is getting shorter. TO recalculate the required change in weight to offset the uphill/down hill secnerio you have to know the tilt of the hill and then do the math to shorten the "seesaw" by the right amount. (for instance if it was a 45 deg hill the distances would change by the sqrt(2) or roughly 1.414)

 

[Beltzington]

the levers link Levers can be updated if you convert your distributed load into a point load. to do that you take the lenght times magnitude =total force and apply that single force in the center of the distributed load.

for instance, a 10 lb load that runs from 0-6' and a second 30lb load that runs from 6'to 10' can be considered a single 60lb load at 3' and a single 120lb load at 8'

as to your question about do the forces change if you change the angle of the trailer (moving up hill or down) yes. anyone that has ever carried furniture up stairs knows that as you tilt the top up, the bottom guy carries more weight, to the point that its vertical and the bottom guy carries ALL the weight. To calculate this, consider a seasaw that has 2 guys sitting on it without any ground under it. As they tilt the seesaw, the distance between the 2 guys gets shorter (again at vertical they are sitting on top of each other) so at some point inbetween, the effective distance between the weight they are applying and the center piviot is getting shorter. TO recalculate the required change in weight to offset the uphill/down hill secnerio you have to know the tilt of the hill and then do the math to shorten the "seesaw" by the right amount. (for instance if it was a 45 deg hill the distances would change by the sqrt(2) or roughly 1.414)

Very clear explanation, thank you.

 

[MossRoad]

The answer is based on the uniform loading of 250lb/ft to get 1667 lb at the hitch and 8333 lb on the axle. :thumbsup:

The forces that you can get into during motion are well out of my engineering experience but I would say that if you are anywhere close to the weight of the trailer being moved i.e. if your tractor doesn't weigh close to 2/3 the weight on the flat, or at least as much as the trailer on a hill, I'd find some creative solution to moving it such as a crane that was mentioned, or someone with some bigger equipment. The last thing you want to do is get beyond your tractor capabilities and have that trailer dragging you somewhere you don't want to be. Is there anyway to put this thing on a dolly to get a second axle under it until you get close and then fix the axle and push the trailer across it so that you aren't fighting another factor?

The equation incase anyone is curious:

Hitch=(W/(2L))*(L^2-a^2)=((250lb/ft)/(2*24ft))*(24ft^2-16ft^2)=1667lbs

Redneck is correct. And MossRoad. I just asked a Professional Structural Engineer licensed in 4 or 5 states. (Hopefully, he knows what he's talking about )

I failed Algebra in high school. I almost didn't graduate. A teacher took me under her wing, made me eat lunch in the teachers' lounge next to her and spoon fed me Algebra for 20 minutes a day my senior year so I could graduate. I got a C. I graduated. She gave me a trophy! Thank you Mrs. D.!

 

[dodge man]

Moss Road, in college I had two semesters of Calculas, statics, dynamics, structural anylsis, structural design and I dont know how to work this problem so don't feel bad. 30 years ago I'd could have figured in a few minutes.

 

[MossRoad]

Moss Road, in college I had two semesters of Calculas, statics, dynamics, structural anylsis, structural design and I dont know how to work this problem so don't feel bad. 30 years ago I'd could have figured in a few minutes.

That makes me feel a lot better. Thanks! :thumbsup:

I'm so glad I don't have to remember formulas anymore. I just look them up on google, plug in my numbers, and off I go. However, this particular problem, there wasn't an on-line calculator or formula that I could easily find. Had to think about it and do a best guess estimate. I knew I'd only be off by, oh, about a thousand pounds one way or the other!!! :laughing:

 

[check]

Look, guys, the wheel idea is just not going to work. Just look at Sodos diagram. Even if you could put a wheel at the appropriate place, lift up the front end of the bridge with the tractor, and then push it down the slope to the creek, as soon as the wheel gets over the edge of the first bank it's going to drop down rapidly and the far end of the bridge will stick in the mud at the bottom of the opposite bank. Then what do you do?

I think Sodo's idea of logs is a much better idea.

 

[RedNeckRacin]

That makes me feel a lot better. Thanks! :thumbsup:

I'm so glad I don't have to remember formulas anymore. I just look them up on google, plug in my numbers, and off I go. However, this particular problem, there wasn't an on-line calculator or formula that I could easily find. Had to think about it and do a best guess estimate. I knew I'd only be off by, oh, about a thousand pounds one way or the other!!! :laughing:

I guess my engineering education was worth something after all! I enjoy helping people solve problems like this because it really gives them good information to base a decision off of. You can always try and wing it and rely on a best guess but you can't argue with the numbers. We always like pics OP or else it never happened! I'm actually pretty curious how this project is going to progress.

 

[MossRoad]

I guess my engineering education was worth something after all! I enjoy helping people solve problems like this because it really gives them good information to base a decision off of. You can always try and wing it and rely on a best guess but you can't argue with the numbers. We always like pics OP or else it never happened! I'm actually pretty curious how this project is going to progress.

Yeah, I enjoy logic problems. The real head scratchers. Like if so and so's father is his mother's uncle's third cousin, who only has daughters, how are they related? :confused3:

 

[RedNeckRacin]

Yeah, I enjoy logic problems. The real head scratchers. Like if so and so's father is his mother's uncle's third cousin, who only has daughters, how are they related? :confused3:

Is that a WV joke? I do enjoy head scratchers too. Esp when you only have a limited means of doing something. There is always the "has to be done" vs "want to be done" consideration though!