 Party Party's not here. Party here. Party Stevens Rottz, Barry, Steinhubble. I only call people that I saw come in, because some people come dragging in late. We were working on welded connections. We had analyzed quite a few of them. Now then we're going to design one. We've got A-36 steel plates. This one is similar to the problem we had in example 712. Here's what it looked like. It had wells on the sides only. Look on page 447, you'll find it. It had an axial load P on a plate welded to a gusset plate. You've got to have a dead load of 9 service, a live load of 18 service, 1.2 dead plus 1.6 live. How long must a set of quarter-inch fillet wells be if you're going to use the appropriate rod for A-36 steel? The A-70 rod has a tensile strength equal to the hog. What's the tensile strength of an A-70 rod? The hog? I'm sorry. A molecule? No, not a molecule. This is not a chemistry class. L-A-H-A-U-G. Oh, I guess you didn't even recognize that. Well, I'll tell you what, I can do this probably. Lucas, how's that sound? Okay, and I'm just Lee. Okay, that'll work. How much tensile stress does an A-70 rod have? Yes, A-70XX actually. I see why you were delaying the inevitable. 50, very good. Add a little to that, though. How much? You're going a little higher than that. All right, A-70 KSA. That's right. That's why they gave it that name. Okay, you say, what are you picking on me for? I wasn't talking. It was simple, but there those girls say, yeah, well, but if you can't pick on girls, it's not politically correct. So people with names you can't pronounce, they're next on the list. So they're both parts are three-eighths of an inch thick. So whether it tears through the gusset or through the plate, I don't know. Don't care. Yes, sir. I don't know. I don't remember. Think you can look that up? 18 or 14? No, I don't think there's any of those. It signifies what? No, this pretty well tells us the alloy right here. The coating raises, but we don't care. That's how come nobody knows. That's how come you don't know. Yeah, well, no, they don't want to be curious in here. Oh, no, no. It gets you in trouble. All right, so now this one I know nobody's going to get. Let me pick somebody at random here. A car? Yeah, you notice that, huh? All right. So the shear strength per weld is 1.392 times dead. Now, if you say, well, I don't remember where that came from, it came from page 450, where we decided our life might be easy, made easy. We'd find out if we were going to use E70 rods, because they're the most common rods that we use for A992 and A3060 or both, go ahead and multiply the throat size of a 1.16 inch leg size weld times 1 inch and just see how strong a 1.16 inch weld was. And then if we happen to have a 3.16 well, we would just take the strength of a 1.16 inch weld. Since we have three of them, we just multiply it times three to get the strength per inch. So in our case, we have a 4.16 inch weld. So that's a good number to hang on to write it somewhere in your user's manual or your LRFD manual. 1.392 times four gives us 5.568 kips per inch of strength for one inch of weld. And we of course got a whole lot of load to hold up. We've got nine dead and 18 live. It comes from the equation on page 7.34a, page 450. In the sheer yield strength of the base metal, we had the same idea. It wasn't quite as nifty, because in this case, assuming you're going to use an E70 rod, all we didn't know was the size of the weld, and you're probably either going to pick that or saw for it. On the base strength in yield and rupture for the base plate, we don't know what plates you're going to use, as well as we don't know how thick the plate is. So it becomes a little less useful, but still worthwhile. It's going to be 6 tenths. In our case, it's a 36 steel, so the tension, tension yield is 36. That makes it sheer yield. And the plate is three-eighths of an inch thick, both of them, so I don't care which one you're talking about. That's the base metal. That one's going to be 8.1 kips per inch. And it really doesn't matter if we were talking about putting how strong these things are down around each one of these holes where we weld things or where we bolt things down. You can't have more strength on any one inch of this weld than the weakest thing. So if you say, well, once this weld gets on back to the end of the plate back there, it'll have 1.5 times the strength, because it's 90 degrees with respect to these wells. I'm saying I don't care. If you have a strength on this inch of base plate and a strength on this inch of base plate and a strength on this inch of weld, you must take the lowest of those in that weld. So the strength due to yielding along the base metal was a three-eighths inch plate, 8.1 kips per inch. And the strength with the shear rupture, you're going to be able to up that number to 58 for a 36-deal, but you're not going to be able to use as high a fee value. The fee value on this one, if you remember, was 1. So that drops the 0.6 down to 0.45 even though you raised the 36 up to 58. Now if you say, well, this one always seems to control when we just do it, well, you're going to have some metals that that doesn't happen. It's going to be that this number is pretty close to this number. And then when you apply the fee factors to them, then you'll find out this one takes over. So you just have to check them both. So so far we have 5.568 kips per inch due to the weld, 8.1 kips per inch due to yielding the base metal, and 9.7 due to rupturing the base metal. So we're going to have to take the lowest of those three. Then 39.6 kips, somebody calculated how much load we were going to have to have on that thing when I wasn't looking. There it is, 1.2 dead of 9 plus 1.6 live of 18, 39.6 kips. We have the strength of our weld is controlled by the 5.568. And so I can tell you how long the weld has to be 39.6 kips divided by kips per inch. This is assuming there's no weld on the end. Did he tell us that? Yeah, he did. If you remember the original problem had weld on the sides only. So he's not in that dilemma. Should I take the 1.5 and only get a piece of these? Well, how much piece did you get on these? One, no. You got one, one, one, if you had end welds and you were willing to live with one, one, one. But if you wanted to, you could take this one times one and a half, but then these had to be cut down by how much? 15 percent down. That was a 0.85. That's correct. Take your choice and you got the larger of the two, which is an unusual gift, but true. That doesn't apply to us. We don't have an end weld. So you need 7.11 inches. They're probably going to round it up to seven and a half, maybe eight inches, four inches on each side. No matter what they do, when they only put four inches down this length, somebody's going to have to go back and check this plate because this thing here may have a U of zero. Are U of 0.75? Are there several U's, values in there depending on how long is the weld and how far are they apart? If to scale this thing is drawn like this, there's your four inches and there's your four inches. You're not going to get much load out of that. That load's going to have too hard of a time getting through those little four inch welds. Did he tell us what that distance was? I don't remember. He may have, but it still has to be checked. Yes, ASD. No, thank you. Practical design of welded connections. I'm sorry. I missed the very end of it. This one. Okay, we got the 7.11. He was going to use eight. I was thinking that you could going to have to have four inches on each side. I was thinking that he could use, well he really can't, can he? Three and a half on each side, three and a half, three and a half. That's only seven, so that wouldn't work. So round it up to the nearest inch. That's eight inches total. Four inches on each side. All right, practical design requires a consideration of things like you already knew this, minimum, maximum weld sizes, short lengths, long lengths, the whole nine yards. We already covered that and we discussed it by looking at the AISC, the LRFD, the specs. They were listed in J22B. They're on this page, in our notes, they're on that page in the text. A quick summary. They can't be too small. Nebel, Ibel. You're right next. The other guy I can't pronounce his name. Okay. And you both got the name Taylor. What am I going to do about that? Okay. Nebel was wise the minimum size of restriction. Do you happen to remember? I mean, okay, well it's not unusual. This stuff goes pretty fast. Graham, you remember? Graham here? Graham, you remember? You'll remember something. Say the word heat. Very good, heat. That's right. Clark, where's Clark? What kind of heat? What's wrong with heat with little bitty wells? Did little bitty wells get hot when they lay them down in the fillet down in the corner there? Yes, they do. That's good. Wells get hot. Can too. There's can too. Berry, never mind. Brown, picked on berry. Brown, broon, barn, broon. Well, they get hot and if there are little bitty wells down in that corner, those little corners just suck the heat out of them like crazy. Didn't we discuss that? You could, and if you're willing to do that, then this probably won't matter. And then you're going to let the whole thing cool off nice and slow. But that's not cheap. So there's a minimum size and the specs let you get away with it if you want to do it, but then you've got to preheat the metal. Maximum size. Well, they don't want the thing to be too big because you burn a corner off this and I won't have a way to inspect it up to a little less than a quarter inch. At a quarter inch, you've got to leave me some corner. A little less than a quarter, they don't think you'll cheat. They don't think you'll just burn a corner off out of carelessness that you probably can develop that well successfully. Minimum length, it couldn't be too small. Maximum length, it couldn't be too large on end loaded wells. Minimum length, by that I mean too short. Here was the factor that you had to go by if you were going to have an end loaded weld. Here's an end loaded weld. I have that I'm talking about. Here's the load, the weld, and it's loaded on the ends. If you have an end loaded weld, it takes a while for these loads to get out way on down here. If this is a hundred inches down here, you've got to have a whole bunch of stretch in this well before the member can deform to get load on down the road here. So they will put limitations on how long they can be. Past 300 times the well size, forget it. You can put all you want down there. You're not getting any more 180 times the well size. Discusses end returns. A lot of times it's just to make sure that the weld has an appropriate size all the way down to the end. You can count that in some cases. Cost. Here is a quarter inch weld, for example, and somebody needed twice the throat. And so rather than making this a quarter, they made it a half inch weld. In changing it from a quarter to a half inch weld, they multiplied the volume times one, two, three, cost them four times the cost. It's a direct cost of the volume laid down in the groove there. Cost them four times the volume or the cost as you got out of added strength. It's twice as strong, four times as much money. Another example. Got a half by four 836 plate tension member. Got six dead 18 live. Going to be attached to a three eighths. Okay, right off the bat. Are these both 836? Yeah. This is the one that'll tear. So when we're calculating the base metal shear, it's going to shear right along the edge of the weld probably either all the way around or if it's just got welds on the sides next to that. Wants to design a welded connection. Base metal, say 36, E70 rods. Somebody at random here, but I can't find him. Got so much for the word random, huh? Taylor. Taylor. What does this right here mean? Last name. The other, the other Taylor. I'm sorry. Your last name isn't Taylor. Your first name been Taylor? Your dad's name been Taylor. Your mom's name is Taylor. Yeah. Okay, well, that's too bad. I thought you, but oh, I bet I know what I was looking when I was looking at the other guy's name. Somebody next to him had the name Taylor. Okay, you. Yeah, you. What does this right here mean? Good. It has 10 strength, 70 KSI. That's correct. There, if that's true, then what is the shear strength? Because this thing is, does fail in shear. Well, no, because steel is usually weaker in shear than tension. Remember the number by how much? You need to see if your name was Smith, you wouldn't be having these problems. I didn't say everyone tell anyone having the problem. Vickers? Where's Vickers? Taborga? Tidwell? Look at this. You're the first out of three people. Even Mitch, you're here. Do you remember, I don't remember the question. Yeah, 0.6. Very good. Look at that. She got the question and the answer. That's right. Sixth tense is strong. All right. Minimum size. Why are they going to use the minimum size? Davila. They're going to use the minimum size. I'm sorry. Well, it is a place to start. That's not fair. KSI, what other reason would there be to start with a minimum size weld? It's cheaper. That's right, because it's a smaller weld. We just notice if you double the size of the weld, you double its strength, but you four times its price. So the guy says, well, why don't we make them as small as we can? Can't make them any smaller than the minimum or you'll suck all the heat out of it and it'll crack. Or you'll have to preheat the plate. Yeah, yeah, I know. So he's going to start with a minimum. Now what is the downside of making this weld a minimum size? Bowman? Don't know. Not only either, but I'm going to ask that I get an answer. Forester? Forester not here? Gamble? Gamble? How to do a much longer weld, which makes the connection much longer. Now if it makes it too much longer, well, then it just won't be reasonable because you spin up all your money and making this plate longer. So we're going to have to hit a happy medium of some kind. We'll start off trying a minimum size weld. Going to use these 70 rods. The design strength is 1.392 times some magic number of sixteenths of inch you're willing to purchase. You decided to purchase three of them sixteenths. What's going on here? Ooh, that's a mistake. Oh yeah, it says error right there, doesn't it? It's 1.392 times three. I'm not sure if this is still in your book. Sometimes they'll you know, print little pieces to fix things like that. May have the same addition number. 4.176 kips per inch. Shear strength of the base metal is for the thinner plate, 0.6 f of yt, 0.6 yield of 836, thickness of the plate 3 eighths, 8.1. This guy's controlling so far. The shear rupture strength is 0.45 times the change in the 0.6 to a lower number because this had a 1 in it for a fee, this one had a 0.75 in it for a fee, this one had a 36 for yield, this one had a rupture of 58 times 3 eighths. So these are the same numbers we saw before because they were still 3 eighths inch plates. This is going to control and it usually does, they usually have the if they if the well doesn't control there's not much reason to make the well that big because you're not getting your money's worth out of it, you might as well make it smaller if you can. So we're going to go on the 4.176 and say the well strength governs factor load 1 2 dead 1 6 live 36 required length 8.62 minimum length I don't think it's that's going to control you think that's four times three sixteenths can't be any less than three quarters of an inch that very seldom controls and that is less than ours ours going to be one on each side 4.31 oh I've got a couple errors here and so we've not violated the minimum length we can make them 4.31 on each side four and a half inch long for total length of nine inches for this type of connection who's he says side wells must be at least as long as the transverse distance between them that was because if you have something that looks like that this weld here and this weld here if these weld links are shorter than the distance between them he doesn't even give you a you you're lucky to get a zero and so you get no strength at all and so since they're at least as long as this width is he says we can work with that that may take quite a toll on the strength of this plate so you'll have to check the plate he hadn't checked the plate at all as of yet we got to check all kinds of goodies on it so far as well as concerned three sixteenths fill it well these 70 rods total length of the four and a half inches on each side has shown somewhere uh volume proportional cost of the weld true if you use a three sixteenths inch weld to carry a hundred kips of factored load as your 1.392 dead there's 1.392 kips of print for every sixteenths of inch of weld for a three sixteenths weld give you this load we already figured that out so the length of the weld necessary hundred kips over that if you use a three quarter inch weld uh using a 70 rods to carry a hundred kips it'll have to be 24 inches long volume of the weld base times height times the half times length 0.421 cubic inches that sure isn't a lot of cubic inches is it and using a four sixteenths weld to do the same thing you'd have a 1.392 dead four sixteenths instead of having uh 4.1 you get 5.568 now then the weld length can be shorter it's only 17.96 inches long base times height times a half that's the end area times the length 0.561 cubic inches you just caused an increase in the volume of weld 33 added volume to pick up the same load and i don't know why somebody didn't figure out how much more it cost well i guess it cost 30 cost 33 percent more didn't it oh it cost 33 percent more and you didn't get any added load capacity at all still got a hundred kips of load capacity that's how come we like little welts you're buying you're buying i'm not sure it's six because if you just took the difference in these two there's probably one on each side and so there'd be three inches shorter connection that's correct now once the connection gets to be uh 87 inches long well then we got problems with little wells we're gonna have to step it up weld symbols just so you know what they look like on the plans this little well looking thing is near to me and therefore it says weld on the near side want to use a quarter inch well six inches long this would say on the other side so if you were going to weld back here then you would point to this line and you would say welded on the other side you're going to weld it on both sides all the way around and you would show the little weld on both sides and give the links here i want to do all that you just say i want that size well that means all the way around if you're not going to use the normal rod that they're expecting then you'll put what rods you want them to use you can put all kinds of little things in that tail and that means you're going to do it in the field this probably means you're going to do it in the shop and they have thousands more to tell you everything got another example one eighth inch thick eight inch wide quite a wide plate of a 36 steel uses a tension member to be connected to a three eighth inch gusset plate that's that thick that's that thick gusset plate controls tearing of the base material as shown next page length oops can't exceed eight inches okay that's probably going to influence how small a weld we can put on it as far as that goes we'll probably just go ahead and solve for the size of the well since he's going to give us the length all welding must be done on the close side the near side can't weld that little back piece design a well to get the full capacity of the member well i don't know to tell you the truth yeah yeah yeah uh-huh so if i said well it's no longer max and so i shorten that down to six then this would be six and that'd be six and this would be longer than the distance between them you can do that you just get no strength out of it u is zero so you say well why do it obviously you wouldn't do it now this guy i don't know what the use of one here you know i don't know if he's going to be a one here unless you put a weld across the end of this thing maybe that's what he plans on doing if he does then from somewhere down in here he told me that and i stuck you as one up there design strength got to be based on gross section yield going to be based on net section rupture on gross section yield we got to go back to page eight in the book nine tenths f sy area gross uh feed point nine eight thirty six deal half inch thick eight inches wide 129 kips no reason to make a weld any stronger than that number so far how strong is it based on its effective area says if the wells are going along the sides only we got to go get you then there's you know some question about what you would be however if there's also a weld on the end then area effective is area gross because you didn't lose this little piece of metal on the end he says and let's assume the ladder okay so we got a weld on the end you as one you could also be one depending on how long the wells were if the wells were long enough this eight inch would be okay if he didn't have the weld on the end so far uh f sub u instead of f sub y and a point seven five instead of a point nine gross area point seven five fifty eight for a thirty six steel half inch thick eight inch wide hundred seventy four kips could care less still not going to design my well to carry any more than this incidentally when I designed my wells somebody has already factored the load so I want my I want my wells also factored when I do the design in other words if you've got well numbers running around loose where they say r sub nominal is equal to so many kips per inch I don't want to be I don't want you to be using that I want you to go ahead and have a fee times r sub n per inch because you've already got the fee in here if you want to take the fee out of this calculation then uh then you can design the wells based on their nominal strength but it has to match up so we're going to go for 129 kips with e 70 rods table j24 this page tells you the minimum size is three sixteenths however he says because of the length restraint go ahead and try a slightly larger well quarter inch well okay uh the design strength the factored strength that's got the fee in it already you're going to try a quarter inch well four sixteenths five point five sixty eight checking the base metal shear no new numbers here because there's still three eighths of a thirty six steel eight one and nine point seven the weld controls there's both longitudinal transverse wells are going to be used we'll know how long the longitudinal wells are these are these length wells says let's try both of those options first assume the same strength a hundred percent a hundred percent a hundred percent for everybody in sight well eight inches of this strength weld would take out eight times that number and leave us with some load to be carried by the side wells total length of the well required was 23 point 28 taking eight inches out of the total of 23 that we need leaves us with about eight inches on each side so probably going to be using eight eight eight if we just count a hundred percent hundred percent a hundred percent for the second option you're going to get only point 85 of the five point five but you're going to get a hundred and fifty percent of the five point five on the ends so hundred and fifty five point five gives you eight k s kips per inch on the ends you need a hundred and twenty six kips minus you're going to give me eight point three five per inch on the ends so the difference is sixty seven sixty two point seven for the two sides that's left for the sides and the required length of the longitudinal wells total load divided by yeah that's right so there's the four point four seven half of the load goes on one side half of the load goes on the other side here's the strength of each side per inch six point six three inches now I don't know we've got a problem here uh because all of a sudden now we don't have this thing here we've got this and this is only six I mean that's nicer I'd rather have seven inches I'm not gonna I'm not gonna ask that welder to do a six point six three inch weld he'll stick a rod up my nose seven inches this is eight is that gonna cause some eyebrows to be right raised no that's correct why not because you have transverse weld I mean no question we've been so busy making sure that this distance across here wasn't shorter than these wells because then without that there we had a u of zero but as long as we had this across the end all these little people can get out these doors and these can get out these doors very gracefully there's nobody running over like crazy like if there's no weld on the end all trying to get out the side doors and bunching up and causing a u to be less than one so that's okay still got all the old friends to calculate block shear in the thinner plate we'll bother that same old same old add a block shear strength with an upper limit of design strength turned out to be bigger than our gross section yield on the plate itself and our wells were bigger higher strength than that so we're good to go loud stress design a you would if the wells were a higher strength you would pay a little more for the higher strength rod you have to make sure you keep track of who's got one and where they're at make sure they're putting them on the right connection probably the guy's going to say look unless you're going to use those different rods on the third floor and above I don't want them just over in the ballroom and over in the saw and saw because I don't know my guys will be that careful no no block shear turned out to be a number higher than the gross section yield block shear once you got it all said and done 287 and then times fee still is 216 this was our gross section yield that's the limit there's not much you can do with that that's just flat based on the yield of the plate I'm sorry I don't think so I think the 196 was way back from day zero see that was back when we first found the gross area and gross section yield then we designed the wells so that they would not fail so we at least get the full strength of our plate all right now those are simple connections a simple connection is one where the resultant of the load goes through the centroid of the bolt group or the centroid of the weld group so if you have a weld on an angle here's an angle and you will find we'll talk about it later on that sometimes it's to your advantage to make that weld longer than this weld because the centroid of the angle is here looking at it from the end so you put so you don't get eccentricity in it don't know why I told you that and then here's the load coming down the centroid of the angle and then the centroid of the wells matches with the centroid of the angle that's why that is now still a simple connection but if you say yeah well I don't think the code really or the specs say that I'm gonna put six inches of well put six inches of weld and I'm going home you put your load wherever you dang well please well then that is a then that is not a simple connection because the centroid of your weld group six inches six inches is in the middle here is your load off by two inches that is not a simple connection that's an eccentric connection you may not have to handle it the specs may say that's okay reasonable and other times they'll say that's too far you must take into account the moment caused by that force times that eccentricity so if you have a load here at the center of something and then the wells are like this because you can't get to that side that's okay you can do that we do it all the time but you will have to admit first you'll pick up the load p and you'll put it at the centroid and you'll distribute that load p uniformly across the entire connection and then you'll have to come back once that's finished and put a bending moment p times e and handle that moment part on the connection or generally that's done when you have a plate that looks like this welded to a column and you just weld it and the loads out here then you'll take that load and you will pretend it's on the centroid of the weld and that all 50 kips comes out in all 10 inches 50 divided by 10 all the way around then you come back and on this weld group you put a moment p times e to handle that part of the load on the connection read this here are typical connections these will be bolted for a while number one the bolts are in pure shear where you see a number two they're in shear and in tension here is a side view of a beam bolted to a column here is the end view of that beam bolted to a column if you look at these bolts if you look at these bolts here and you cut it loose from the column and you ask what's going on with this angle there's a shear force acting up on the angle because there's some loads acting down on the beam and that load is eccentric from these bolts since that's the case the first thing I'm going to do is I'm going to pick up this force R and I'm going to put it at the centroid of the bolted connection and I'm going to tell you the force on that bolt is r over three r over three r over three there's that bolt there's r over three on that one there's not room there's r over three straight up on that one there's r over three straight up on that one since this load does not truly go through the centroid of the bolts that we are now analyzing it's out of distance e you will have to put a bending moment m that'll be r times e r times e clockwise means that it's going to pull on this bolt it's going to push on that bolt and it's not going to do anything to that bolt because that bolt is on the centroid of the bolt group this number was r over three this number right here has to keep this thing in equilibrium since that moment is equal to r times e then this force multiplied times the bolt spacing plus this force times the bolt spacing those two two times the force in shear times the spacing has to cause a moment r times e that's how you'll solve for f sub v f sub b is equal to the reaction force times the eccentricity divided by two times the spacing that's if there's two bolts if you got four bolts or eight bolts or 11 bolts obviously it's a little more complex the interesting thing is is when you push this angle up on this girder you shear the bolts in shear you load the bolts in shear you wipe this face across that face and shear the bolts when you put a moment on this angle you also wipe the bolts you push this point right back you push this point to the left and you shear the bolt therefore the force in the bolt is r over three in shear squared plus this force in shear squared take a square root and these bolts are loaded in these bolts are loaded in shear now then instead of looking at this free body let's look at the column with the bolt the bolts attached where the force r the same force r that was on the last one is down through these three bolts now we're talking about these people here first i'm gonna you see it i do it all the time i lie i picked the load up and i put it at the shear plane in other words i say e is zero you say no it's not i say well until i say otherwise right now it's right there it's okay be that way then i'm going to show you a force down on this bolt at this shear plane right here and that force is r over three and there's one on that bolt and there's one on that bolt and there's one on that bolt now then i'm going to admit that i have a moment that goes this way about this centroid it's magnitude is r times e there it is right there m is equal to r times e it's going to pull on that bolt you'll notice it's not shearing the bolt now on this connection it's a tension force on that bolt and this one is compressing the bolt now the truth is it's not compressing the bolt it's really compressing these two surfaces but we assume that it's just pressing on the bolt and since i'm going to design this one for that tension the fact this one doesn't really have that tension or compression force in it i don't care it's really just going to get pure shear still the force up here is going to have to say t times s plus t times s is equal to r times e going to be the same tension force there as we had a shear force here the problem is i can no longer do this i can't say that's r over three and that's equal to t i don't know what it is whatever it was up here i can't say that that's well i can say that and that is what's going on in the bolt but a minute ago you could design this bolt for shear period go home what do you have with what do you have to do here what is it biaxial okay biaxial sounds about two axes give me something else that sounds like two interaction equation it's nastier than biaxial bending oh i guess not really because biaxial bending you got an interaction equation you got to do all that interaction stuff first you got to design it for shear make sure the shear is not too big then and once you do that you find out if you got any tension left over for you and then if you got any tension left over for you you can check it against that force there so this connection is not the one you want to see on the quiz this is the one you want to see on the quiz now there's two ways of doing this one's called is not called it is an elastic analysis what you do is you take the load and you put it at the center or to the bolt group and you distribute the load uniformly between eight bolts then you take the load times the eccentricity and put a torque on it and you apply a tc over j equation to it doesn't exactly fit the real world because tc over j was derived for a solid cylinder uh flat circle but it's plenty close and it's a little on the safe side so we will get some forces that go this way and some forces that go due to the twisting and then we stop the world whenever the first bolt yields now that leaves us with a lot of strength there that we haven't accounted for number one the fact is this bolt can yield it can go past yield allowing the next bolt to yield and then he can yield and then the next bolt will yield and the next bolt and first thing you know they may not all get to yield because for instance to get this one to yield you might have to roll that plate 50 degrees so when one of these bolts reaches a real honest goodness max that we have to quit then we'll quit on the whole thing but believe me picking up all these other people's additional capacity is quite uh an increase in the number so we're gonna have an elastic analysis then we're going to have a plastic analysis so we'll work on those next time it's getting time to drag your quiz by since you found that uh i can't even add right five points to your detriment you need to bring those up pretty soon a few days or have you got cheated in any respect thank you