As I have already said, It's hard sometimes for things to be interpreted the way they are meant on a internet forum like this. I have tried to explain my plan the best I can but you only seem to pick on pieces and parts and not the whole picture. I didn't mean for you to think the beam was going to be solely supported by the roof truss system. I tried to be clear with what I was saying but you seem to be hung up on the all the if's, and's, and but's of the job, and the legal aspects of it not being an engineered stamped design. This is a pole barn, built on agricultural land and for that I don't even need a permit. It's not a commercial building and is only put here for me to tinker around in now I am retired.
Over my life time I have built a lot of tools, equipment, roads, small bridges on farm land to haul pulp wood and logs out of the woods and countless other projects with the help of only what I had on hand at the time. One of the old truss bridges I built 30 years ago is still being used and has stood up to parades of logging trucks all that time and they just finished logging another 800 ac's and brought it all out on that little makeshift bridge. I'm not saying I know everything, or anything at all all I am saying is if what I have been using in the other shop has worked all these years I cannot see why this would not accomplish the same since it is 10 times the steel of the other rail that has worked for so long.
Now, I said I could support the beam if needed in several places to the truss system of the building and have talked to the truss people about beefing them up just in case. The BEAM I am putting up IS basically a truss in itself designed by ME to carry it's own weight plus the weight of the chain hoist and hopefully at least 1000lbs which would be at the most remote possibility. 300 lbs max would be the weights that would be picked up and rolled from one end to the other and even then something that heavy could be supported by a shop cart as it is being moved.
I wont be able to put the upper supports on the beam until the roof truss is in place because these braces will have to be intertwined through and around the roof truss. My test criteria may seem a little caveman style to you but I figure if I can hoist the test load in center span with nothing but end supports and it swing for a day in the open without failing I should have no problems once the truss beam is fully completed and braced. Then, hopefully OSHA wont start inspecting farm buildings to see if they have engineer stamps on all the lifting devices in the hay barn.LOL
Results 11 to 20 of 47
Thread: I need to make a 20' I beam 40'
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03-09-2011, 08:36 AM #11
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03-09-2011, 02:15 PM #12
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03-09-2011, 09:21 PM #13
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3 graduate engineers were discussing who might have been responsible for the design of the human body.
The first one said "Think of all the joints etc. it must have been a mechanical engineer".
The second one said "No no, what about all the electrical impulses and nerves etc? It must have been an electrical engineer".
The third graduate was shaking his head, "You are both wrong, the human body was designed by a civil engineer - who else would run a waste pipe through a recreational area"?
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What is the difference between Mechanical Engineers and Civil Engineers?
Mechanical Engineers build weapons, Civil Engineers build targets.Steve
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03-10-2011, 06:48 AM #14
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Hehehehe........Thanks I needed that but you owe me a keyboard. I try not to poke fun at computer geeks and engineers because one day I might need my computer worked on he will probably need somebody to draw up a set of plans for him to get out of bed by. I have a cousin that is a mechanical engineer and this guy has always been pretty good with fixing stuff. Before he went off to school and got all smart he worked at a car dealership and could fix anything. Every mechanic shop and dealership in the area wanted him to come to work for them and run their shop. He was making good money at the time but thought the grass was greener elsewhere so he decided to go back to school and become an engineer. Actually that was his dad's dream not his but he finally gave in and went off to school to get really smart.
Five or six years later he was out of school and unemployed for the first time in his life but finally went to work for Reynolds Medal and and worked there 4 years until the shut the plant and he was unemployed again and since then has worked for a couple other big companies and suffered the same fate now he is back at the car dealership he started out at and is happy. The owner of the dealership is a friend of mine and we were talking one day and I asked how my cousin was doing and he said great and it was good to have him back. I could tell from the look on his face that he wanted to say something else but was holding it back and I asked what it was. He told me it's great to have him back but I wish I had all of him back....the old mechanic that went off to seek greener fields years ago. I said, Oh yeah what do you mean?
He said, Well back years ago when he got a job in the shop he would do a quick visual inspection, listen to the engine, put his hand on the part in question and feel for unusual vibration or noise and go to the parts room and get a part, put it on the car and after a quick test drive the customer was happy with the bill and on his way. Something has changed since then because now the first thing he does once he picks up the work order is to go the parts room and picks up 5 or 6 service manuals then he goes into the mechanics rest area and sits down and reads manual after manual sometimes for and hour or so before he even looks at the car. Then it's back and forth from the car to the service manual until I finally have to go remind him that he is not working on the space shuttle that it's only a 96' Plymouth that needs an oil change so use the head the Good Lord gave you because this ain't rocket science.
His wife was fussing about him a couple years ago when she was trying to get him to fix a leaking pipe under the kitchen sink. After about two and a half hours she went in to check on him because it was so quiet and there he was sitting on the floor drawing out plans to rip out the whole wall to replace the whole piping section when all that was wrong was a loose fitting. She asked him what he was doing and he said he was doing the pre work drawings so he could go to the county to check to see what the codes required before he could do the job. At first she thought he was kidding and playing around but she soon realized the **** fool was serious. She then told him, I'll tell you what you are going to do. The first thing you are going to do is get all this crap out of my kitchen floor, then you are going to go out in the garage and get me a small strip of Teflon tape and I'll fix the **** sink and then you get the **** out of my kitchen.
He's getting better now, he really is and is almost back to his old self. Every now and then he will have a brain fart but either one of the kids or the wife will smack him on the back of the head and get his attention. Sometimes things like this just take time.LOL
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03-10-2011, 07:29 AM #15
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I’m not endorsing your project in any way, but for what it’s worth…
For a steel beam with actual dimensions of 9.88 x 3.98 x .189 web I calculate the stress at 10 feet from the end support to be 8000 psi with 1000 pounds at that location resulting in .8 inches deflection. With 1000 pounds in the center the stress is 11000 psi with 1.4 inches deflection.
The yield stress for A36 steel is 36000 psi.
As stated earlier moving loads will create higher stresses than static loads, how high depends on how they move. Having a chain slip, load falls, and then stops sharp will cause a much higher.
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03-10-2011, 07:54 AM #16
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03-10-2011, 07:54 AM #17
"Thanks I needed that but you owe me a keyboard" LOL...lol.....lol (Quote from MX842)
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03-10-2011, 08:13 AM #18
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Thank you very much this is what I was hoping someone would post for me. I have tried to figure out my beam specs but can't seem to get it right. I found that site that does the math but that site won't let me back on I think they want money before I can get the info I wanted and everyone else seems to get caught up on some detail I said and it goes downhill from there. Like I said I'm not the best question asker when it comes to stuff like this. It must be the ADD I have had all my life that gets in the way.LOL
Your beam specs sound like a W10X12 beam which is lighter than the one I am using. If I might trouble you and you have access could you please run the numbers for a W10X19 for me? Actually I'm not 100% sure the real value of the beam is because yesterday I weighted a 4' section and it weighted just shy of 85lbs so that means it's at least a W10X19 or more but I don't have anything showing a beam with measurements that match my beam size and weight. So going by the weight Of my beam material I should be safe going with the W10X19 numbers and have some built in overload protection.
I want to know this because I would like to find out what is going to happen at 20' mid span with 500Lbs and then at 1000lbs with just support at both ends. Please forget about all the what if's and maybe's for now. I plan on dealing with those with additional bracing and support. I just want to know what the beam is going to do at these points so I can figure out how much and where to place the bridging I am going to do on the top of the beam to support the load. I need to do this so I can order my roof truss and I need to know what style truss system to put in so I will have enough room above to run my steel bracing for the beam.
PS: I don't like lawyers either so this is not a trap I'm trying to snare you in so I can sue you and I realize anything I put up I am responsible for and if it falls down in a pile of rubble one day the board engineers can reserve all rights to say, I TOLD YOU SO.....Last edited by mx842; 03-10-2011 at 08:18 AM. Reason: Adding point
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03-10-2011, 09:32 AM #19
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A simple beam calculation for a W10x19 beam, 40 foot length, supported at each end with 1000 pound load at center comes out to 6400 psi stress with a .83 inch deflection. Half the load results in half the stress and deflection in this type of simple analysis (3200 psi, .41 inch deflection).
I would suggest in asking pointed questions, like "what is the theoretical deflection for such and such" rather then open ended questions like "I'm planning on ..., will it work". People are hesitant to give opinions on stuff like that because there is a lot at stake if this thing comes down. And there are a bunch of reason it could even if the material has inherent strength in theory.
Beam deflection and stress are useful calculations but they can't take the place of a detailed engineering analysis. I think you know this already. So, you are on your own. Good Luck.
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03-10-2011, 11:36 AM #20
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Thank you, and you are right about how you ask a question and getting results. I tried several different ways at other sites but when I did ask that pointed question on one site and my only response was.....well, go out and spend you $150,000.00 on a college education and you might be able to figure this out all by yourself. I guess he is right though but at 65 years old and broke as I have become over the last several years with this economy I don't think a college degree in in my future.LOL
Once I'm done I'll post up some pics of the completed project if I can figure out how to do it on this site.











