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Got a job coming up soon. It will be 3 awnings just like the one in the first picture. So I am debating which style base to use. Your thoughts on picture 2 and 3 ? Which will provide more support. Will be anchor bolted into concrete using 9/16" bolts.Also, on the cantilever design, do you think I can build it without the long beam underneath? I would like it just to be the top beam, and the smaller counter beam at the rear. I think building code says only 1/2 of the length of the joist. But this is a little different because of the angle of the top beam and the angle of the counter beam. Big tubes are 4x3, smaller ones are 1" square tube, and roof material is corrugated tin. Attached Images
Reply:Just flip the cantilever to the top of the posts.Miller Thunderbolt 225Millermatic 130 XPLincoln HD 100 Forney C-5bt Arc welderPlasma Cutter Gianteach Cut40ACent Machinery Bandsaw Cent Machinery 16Speed Drill PressChicago Electric 130amp tig/90 ArcHobart 190 Mig spoolgun ready
Reply:As STwelder said, put the long diagonal to the top so it's in tension supporting the overhang rather than compression. Another thought, just an opinion, the diagonal wouldn't have to go to the end of the structure neither, I think it would look a bit better and you would have less chance of the horizontal member twisting since there's no intermediate braces.Go for the second base design.....MikeLast edited by mrmikey; 06-26-2009 at 04:54 AM.
Reply:Just a recommendation, but if you're still bidding this job, and these are custom fabrication, you might consider including the cost to have a structural engineer review the design. This is something that could fall and damage property or injure someone. It's got to withstand wind and rain in your neck of the woods. The money spent getting a structural engineer, with a professional engineer's stamp, is money well spent. An architect might also be able to do what's needed, depending on the rules in your state.A good engineer might be able to save you some money on material as well. They'll recommend the: correct size fasteners for the base, size of the load bearing members, and the other materials used. One other thing to consider is whether or not the base needs to be installed in concrete footings, or if the existing slab will suffice. All this will depend on your local building code.Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:Just curious for myself - why flip the cantilever? Making sure I understand what you mean - taking the "triangle" created by the roof line, front & rear diagonals - then flip it so the two diagonals "hang" of the main post down to the roof?Reason I ask - we have several of these structures in a nearby park with the same configuration as the JC's sketch. The construction is wood (pretty beefy wood beams) supporting an arched metal roof.I'm actually planning similar structures for my yard to get some shade to sit in and was considering a design similar to these nearby park structures - only out of steel.PS _ Sorry JC - not meaning to hijack here..Miller Dynasty 200DXHypertherm PowerMax 45Victor OAIR CompressorLots of blacksmithing tools and other fun toys meant to creatively disfigure, reshape, manipulate and join metal.
Reply:JC--great confusion is mine.. under the tin roof i see a horizontal(flat-no pitch) beam (3) supported by a vertical post()3) which is nearer to one end than the other-are you asking if okay to eliminate the braces?you want it to be just the top beam and the small counter beam at the rear--aint that all one continuous beam under the tin roof?why not put the post in the middle and eliminate the eccentric loading?
Reply:Originally Posted by weldbeadJC--great confusion is mine.. under the tin roof i see a horizontal(flat-no pitch) beam (3) supported by a vertical post()3) which is nearer to one end than the other-are you asking if okay to eliminate the braces?you want it to be just the top beam and the small counter beam at the rear--aint that all one continuous beam under the tin roof?why not put the post in the middle and eliminate the eccentric loading?
Reply:Originally Posted by STwelderJust flip the cantilever to the top of the posts.
Reply:as for the anchoring id go for picture number 2, as theres more surface area of the gusset across the horizontal and vertical plane of the beam. as for the cantilever , you could flip the cantilever but still have a solid roof, have a bolt patern at the top of the main beam, that a support beam bolts onto from top and two steel wire lashings suspending the roof. transferring the force to the center beam.!!! maybe too complicated? Last edited by roco; 06-26-2009 at 02:22 PM.
Reply:JC's Welding,Now this whole thing is getting scary. I didn't comment about your taking on the fence rail project because, it seemed, that no one would get hurt if you screwed up.This latest "project/bid proposal" isn't in the same league.Maybe it's a product of the times (weak economy) but it seems that there are more and more "come lately's" that have a basic welding machine and are now "marketing" themselves as "professional welders".I don't know a thing about your qualifications to do said job, however, based on the equipment (welders) you've mentioned and some of the "rather basic" questions you've asked in the past, are you sure you're set up to even do this job. Seems that the first thing you do, when you hear about a potential job, is post up a bunch of questions about how to get it done. That's a rather weak business plan in my book.Do you have a business license to operate as a welder? Do you have the structural qualifications/experience to be designing such a structure? Do you have adequate insurance to cover a failure? Have you ever done this type project in the past? Do you have the equipment to do the job properly? ETC, ETC.As a registered PE (Professional Engineer) I can unequivocably state that "internet suggestions" cannot replace the guidance received from a structural engineer. This isn't a stand someone's going to hang a gong on in their backyard. People could get killed if this structrue should fail.Poorly designed or badly executed work is a negative reflection on the entire welding community.I guess it's just been awhile since I've seen a "business owner" who relies so heavily on advice he receives from an internet forum. Some of the information you receive from such a forum can be good, however, some of it is not only wrong but downright dangerous.Off the soapbox.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:You are very much within your right to be on a soap box about this. And, of course, your points are valid and well taken. I told my wife last night that I wasn't going to take this job. It's way above my league, and so much different that the little jobs I have been doing. I do have another full time job. This isn't my main thing, yet. Maybe in a few years. Like I said in my very first introduction post, having my own welding business is something I would like to do, when it gets to that point. In the mean time, I get great satisfaction out of the little jobs I do on the side, or on weekends, like that stupid fence! Originally Posted by SundownIIIJC's Welding,Now this whole thing is getting scary. I didn't comment about your taking on the fence rail project because, it seemed, that no one would get hurt if you screwed up.This latest "project/bid proposal" isn't in the same league.Oh, I know... read above.Maybe it's a product of the times (weak economy) but it seems that there are more and more "come lately's" that have a basic welding machine and are now "marketing" themselves as "professional welders".I don't know a thing about your qualifications to do said job, however, based on the equipment (welders) you've mentioned and some of the "rather basic" questions you've asked in the past, are you sure you're set up to even do this job. Seems that the first thing you do, when you hear about a potential job, is post up a bunch of questions about how to get it done. That's a rather weak business plan in my book.Most of it is just my enthusiasm. Even though I will not be doing this awning job, I still enjoy drawing it up, asking questions, and researching it. I learn a lot doing it this way. I will continue spending the weekend drawing it up on the computer, just to be doing it.Do you have a business license to operate as a welder? Do you have the structural qualifications/experience to be designing such a structure? Do you have adequate insurance to cover a failure? Have you ever done this type project in the past? Do you have the equipment to do the job properly? ETC, ETC.As a registered PE (Professional Engineer) I can unequivocably state that "internet suggestions" cannot replace the guidance received from a structural engineer. This isn't a stand someone's going to hang a gong on in their backyard. People could get killed if this structrue should fail.Poorly designed or badly executed work is a negative reflection on the entire welding community.I guess it's just been awhile since I've seen a "business owner" who relies so heavily on advice he receives from an internet forum. Some of the information you receive from such a forum can be good, however, some of it is not only wrong but downright dangerous.Off the soapbox.
Reply:Several have posted they feel that column base 2 is better than column base 1.I'm curious as to WHY they feel that way. Also for any that may be engineers or designers whats your take on the explanations.My thoughts would be that design 1 is better. It's been awhile since I studied structures and engineering, so I'm just looking to see if my thought process is faulty or not.With the braces in the corners, any side load in line with a face, is taken up by all 4 braces rather than just 2 as well as the 2 parallel sides. Any side load in line with the braces has 2 braces and the 4 sides of the post to work against. With the braces in the corners, the sides of the column can take and resist the force of the brace. you are pushing against 2 "thick" members. If you use idea #2 you are loading a flat unsupported surface and only the thickness of the column side keeps the brace from buckling the tube.In all honesty, I doubt either design would make much difference, as the brace would need to be fairly large to add any serious stiffness to the column. Most likely the column would just bend above the brace once the load passed the ability of the column to resist it alone.The only use I can see for this sort of thing, would be to spread the down load from the column to the base plate in order to limit punch thru and overloading a footing in only the center spot. In order for this to be the case we'd need to be talking about a column for a massive high rise not a tiny shed roof.Thoughts?....
Reply:I was thinking gusset design #1 also. I also came up with this design for the awning. Seems it would be better, and have more weldable area. Attached Images
Reply:JC,I think it was a good idea to turn down the job. The best advice is, If you dont think you can safely build it, then turn down the job. It would be safer and cheaper (law suit) in the long run. There is no problem in saying "I am sorry but I will not build/weld/fab this for you, I can however recommend some other welders that might do it for you." In this time of day, you have to cover your A$$.
Reply:Originally Posted by JC'sWelding I told my wife last night that I wasn't going to take this job. It's way above my league, and so much different that the little jobs I have been doing.
Reply:Yes, I did pass on this, called this morning to tell them. But like I said in an earlier post, I will probably spend the weekend playing with the design. Nothing wrong with that, is there? I'll probably come up with 5 more designs over the weekend.I'll have to call my insurance guy on that. Good idea. I'm sure it's just a GC type. It's through Scottsdale Insurance.
Reply:I dont think the 10x9 base is anywhere close to sufficient regardless of the gussets.Wind Load and the assymetrical design , regardless of the brace location you will have the lower member in compression attempting to buckle the column.as others have said, unless your building this to put in your own property it needs to be looked at and approved by an appropriate engineer.I can refer you to a good structural guy if you need it.insert thoughtful quote from someone else2000 Thermal Arc 300GTSW 3.5 hours1946 Monarch 20 x 54 Lathe1998 Supermax 10x54 Mill2004 Haco Atlantic 1/2" Capacity Lasernot mine but i get to play with it
Reply:chenry,I could highlight a whole list of potential errors in the proposed design (starting with the anchoring system), but I won't.To do so could be interpreted as providing recommendations as to "how it should be built" and come back and bite one in the lower posterior.I think those with a structural background understand where I'm coming from.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:If I ever did anything on this scale, I would definitely be looked over by an engineer, and the city engineer too. In the mean time, I will continue to enjoy the little jobs I do.Thank you, truly, for everyone's input.
Reply:i cant see why that redesign would not fall down .
Reply:You, repeat....you do not, and again....do not ...... put a gusset in the middle of the tubing wall unless you have something to transfer the load to the shoulders of the tubingUprights may be fine depending on the roof load, thickness of the uprights, and anticipated wind and snow load. And the dead load.This is some pretty serious stuff you're gettin' into.It's done all the time, look at the last gas station you went to, but it's engineered to take the stress. Uplift, shear, etc.............. There's torsion too. It's a complicated mess.If you're not up to it, walk away, and no harm done. You cannot design/build something that isn't something that you live with. I'ts a whole different world.I see lawsuits in yer future"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Weldbead.... It's all about a live load as opposed to a static load. My little steel rack didn't even have to take into consideration a live load. It's static.Any time you deal with a roof, you're talking about some pretty changeable dynamics.It's about limitations, and knowing when ya reached them.Not tryin' to be an a$$hole, but consider the variables. You'll probably wind up with the same conclusion I reached."Any day above ground is a good day"http://www.farmersamm.com/
Reply:Aw crap, you said WOULD NOT FALL DOWNapology given"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Originally Posted by SundownIIIchenry,I could highlight a whole list of potential errors in the proposed design (starting with the anchoring system), but I won't.To do so could be interpreted as providing recommendations as to "how it should be built" and come back and bite one in the lower posterior.I think those with a structural background understand where I'm coming from.
Reply:Originally Posted by farmersammAw crap, you said WOULD NOT FALL DOWNapology givenGlad to see you walked away from this one JC. Was this your design or the potential customers? just curious. For future references, base plates for just about any thing start at 3/4 inch. Anchor bolts for structural start at 3/4 inch. spread footings, piers, rebar and anchor bolts. The way you said 9/16 made me think of a drive in wedge anchor. Shudder the thought.Lincoln Ranger 8 Lincoln 175 Drill pressLincoln 225 mig Plasma 8 ft brake 52" jump shear |
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发表于 2021-9-1 00:08:17