 Well, this is pathetic a car. I'm sorry AC a are he's not here. I'm Jamali. Barry Barry's here. Bowman. Brown. Bushey. Elzado. Cantu. Carrington. Casey. Chung. Clark. Cook. Curtis. This is more fun than teaching, man. Davila. Estes. Forrester. You know, they told me they weren't going to be here. Galia. Wow, bummer. Well, I think they've got some ocean thing that they had to go to for Randall. No kidding. I mean, they're half ocean people. Okay. I am hardy. He'll big. Okay, well, I'll check him here then too. He's got an excuse who. I won't count them all gone. Johnson. I think there's a lot of people just hiding in with the other ducks here. Hiding behind something. Mace. Mitchell. Navel. Perkins. Reeves. There's no way. Reinhardt. Raymond. Ratz. Savoy. Sudduke. I don't think Steinhub. Oh, there's Steinhubbles. I don't think Steinhubbles in the ocean. Okay, Steinhubbles here. Stevens. Taborga. Thompson. Tidwell. Triska. Vickers. Wiley. There's no way. There's no way. But now then I don't know what to do. Zepeda. I guess not. But you didn't pay me. If you don't pay me, you don't get to get a grade. Come see me if I'm just pronounced your name so badly that I did you didn't know who it was. Oh, is it Smith? Yeah, that's pretty hard. All right. Here's what we've been doing. We've been taking columns that had an initial deflection, had a P delta. If it was just a P little delta, then 8.866 took care of it to some extent, except now we're adding the fact that due to the delta, you have a P little delta. You'll have a little more moments you'll have to add. It'll have to be amplified. Sometimes the amplification factors can get a little aggressive and you should be able to correct it downwards somewhat. If you put a lot of loads on it, same idea, except you already have a big delta, but you again get an amplification and you have a correction. We worked a problem similar to this one. I want you to go through all of the stuff here and make sure you understand it. It's like I say almost exactly the same as the other one. It stops there and all of the tables and references to where you can go find where he got C sub b is equal to one and C sub b is equal to 1.32 and everything and all of the graphs used to quickly get the bending moment capacity so that you don't have to work it out using those equations. It's very similar. It's a column. It's still a column that's actually loaded. It has a load from on the side of it. I'm not sure we did one of those before, but that's where you had to go. Here you go. Well, here's a C sub b. Here is the axial capacity of the column without the lateral loads on it and moments not yet being amplified. I was thinking maybe that's the one we did. Well, because here's another one. There's two of them. This one has a moment about both axes. I guess this was the different one. It has a moment about both axes and it has a moment diagram looks like this. You'll need to know C sub b so you can find the bending strength of the lateral torsionally buckling column. Here's your quarter points and here's your maximums and your half point and that kind of stuff. C sub b is just listed as a number. I think that's the only thing I need to explain when you take a look at this one in practice with it. I forget what he has for C sub b, but let's just say it's here. Maybe I can see it right quick. Amplification reduction. C sub b, C sub b, C sub b. Here we go. For the beam design charge, here we go. C sub b is 1.67. Well, the book doesn't have a 1.67. It doesn't have anything. Our book, the book you get to bring in with you on the quiz, he doesn't have this case. He figures it's not going to happen real often, but it certainly could. Segui has that listed in his tables in the book, so he just says 1.67. But you would have to do 12.5 times m max divided by, I remember, 2.5 times m max plus 3 times m at the quarter plus 4 times m at the half plus 3 m at the 3 quarter. You'll have to work that one out even on an exam. Now you probably won't because you'll probably be smart enough to draw the little picture in users in your LRFD and say it's 1.67 and that's perfectly legal. And here are the calculations. They follow exactly as before. The only difference is rather than having a load coming in from the side, they have nothing but moments on the ends. And your correction factors and things will be a function of m small over m large. If you remember that, we discussed it. So go through the numbers. It does get a little longer than a lot of them. I've tried to really tell you what we're doing, so you don't sit there and say, what the devil's even doing? Strong axis bending, going to get an amplification reduction. You'll have to amplify it. But if you're a positive thinking person, you probably say, well, let me go see how much it can reduce it before I even find out how much I have to amplify it. That's what he's doing here. Talks about the stiffness reduction. Talks about here is your amplification. There's not an AISC. That's the one I was talking about. The C-S-B is not an AISC listed. He tells you how to get it with the moments. You know how to get anything if you know the moment diagram. But it's not listed directly on his page for C-S-B. Sugui does list it on page 10. It's one of the ones he worked out. That's the only reason he can just say it's equal to 2.67. Then here's your supply. We'll be using the moment requests and the moment supplies. Then you've got weak axis bending. Same idea. This is when I drop back and forth between the two books. This is your book if it's got real page numbers on it. If I got like a page 323 that came out of an old book and I needed it, I wanted these pictures. But here is whether or not you use tals. Tals would be as equal to 1. Stuff like that. Here are the graphs that you use. Here's the tail end of the solution. We're still trying to find amplification factors and corrections there too. And do what this note is. Because the flange is non-compact, weak axis bending strength is limited by flange local buckling. Well, you don't care about that. None of that matters to you. Truth is, just come right down here. The tables you use to get the numbers account for flange local buckling because they are production tables. So we were down to the supply about the Y axis. Then you needed to calculate the axial supply. And then once you had all of that, you could plug in the overall equation to see if it was a good column or not. I'll leave it for you to follow through those numbers. It is going to take a little time and some thought. But better that you do it now rather than on the exam. And if you have any questions, let me know. Come see me. I'll be glad to tell you where the numbers came from. All right. Now, connections are critical. I want you to go ahead and read this information, rather than me just read it to you. Most every structural failure I've been called out to go to court on has been connections. Hyatt Regency was a connection problem with 118 people killed. Very seldom do you see the main beams fail. You see them fail, but they usually fail. And then they bend so badly and they pick up the reserve strength from the plastic moment and from the ultimate moment that nobody dies. Everybody screams and runs out of the building, but it usually doesn't collapse on you. Connections have turned out to be a point of problem. Before the Hyatt Regency, there was no real firm handle on who was supposed to design them. In the past, the fabricator, the person who was going to build it, one of those people would design all the connections. And the engineer just knew that and didn't do that. And the Hyatt, that's one of the things that happened. They had an engineer there, but they weren't real comfortable with a weird connection that was being used. And so they sent the thing back. They told the engineer, first off, we can't do it the way you want it. You told us to just put a big old 80-foot rod all the way to the bottom and then move the beam up and put the beam on here like this and run the nut all the way up underneath it. Then put the next beam up here and run the nut up underneath it. I just said, is that what you mean? We'll bit it, but he says, no, no, no. Well, give me your idea. The guy wasn't thinking and he put a rod like this. Then he put another rod next to it, and then the beam he put like this. Well, it turned out if you checked this out, you find out that the load on the beam got doubled by this. In this case, the load went in the rod right through the nut. It only had one floors worth of load on the nut. And this one would have only had one floors worth of load on the nut. This one, you put it together this way and you end up with two floor loads on the nut. So it was doomed the minute they stuck it in the air. Nonetheless, at that time, the courts said from now on, the engineer of record, the guy who's doing the engineering, putting his seal on it, you will be responsible for everything. We don't know if we missed something or not, but like connections have been slipping through, you've been telling us that this guy is responsible. He may be in the lawsuit too, but he's not responsible. You are. So that was settled at that time. You can connect things with bolts or rivets. Are bolts or rivets or wells? This is riveted. It could have just easily been bolted. This is the way they used to make them with rivets. Rivets were hot. The plugs of steel look like that. I'm sure you've probably seen them before. They'd heat them up in a big old furnace and they'd throw them up in the air and good luck. That's why at first I just started wearing hard hats and the guy would catch it with a bucket and then he'd throw it up to the next floor and then somebody would put it inside of the piece of steel to be connected and a guy with a bucking bar, they'd call it, would kind of look like that. He would come and he would mash a head on this end and the guy behind it would hold it so it didn't go anywhere. Then it would cool off and it would shrink and it would hold the pieces together pretty tightly. Not near as tightly as we can do with bolts today, but it would work for 100 years. They don't do it anymore. You may still be asked to go check something's got rivets on it. Can we add another air conditioner on the roof? Then you need how they work. Welding. Look at all the work it takes to put something like that together. First you got to rivet or bolt the angles to the plate, the web plate. Then you got to bring in the flange plates and you got to bolt them to the angles. That gets really messy. Whereas if you just weld it, you just weld the plates together and you're through with it. It's all one piece. Here you'd probably weld this piece of steel to the column before you go out in the field and then they will bring the girder and put it up against there. They'll put a bar that's kind of got a point in it through those holes so that they line up the holes properly and bolt the bolts on there. If you've just bolted and the top is still there then you don't have to check block shear of this piece of steel inside of the girder. Here you see the plate and here you see the bolts from the side. If they do cope that out then you'll have to check for block shear. Typical bolted connection, single shear, means you cut the bolts once. Double shear means you cut the bolts twice. In effect the bolts become twice as strong but of course now you have three pieces of steel instead of two. Here it's welded instead. They weld all the way around. They may weld just a piece of it. As you know in some cases your welding can get to be not sufficient and you may be less than or equal to one. For instance if you did this, welded it like that then because these things are so far apart and so short this piece of steel isn't really being used effectively and you know the equations to account for that lack of steel when this tension load comes down the plate. This would be a simple connection. Everything's running right down the axis of the item. This would be one where it's not a simple connection where you also have bending. So rather than just loading the bolts right down their axis and each one taking an equal amount of load this one has same things equal amount going down each bolt but they're also being torqued or twisted which causes some bending stresses in the bolts. Same way here they've bolted a T to a column and although you will pick this load up and pretend it's right on top of these bolts causing an equal load in each bolt there's also a tendency to put this bolt in tension and although this bolt doesn't really go into compression a lot of times they'll just assume it does the real compression is taken between the bottom of the T and the flange itself. Here's one where they are loading the bolts in tension. So we have several things you have to check bolt and shear connection failure modes most obvious failure mode is you just shear the bolt itself. These are made out of extremely high strength steel 120 150,000 psi steel that way we can make them small if we can make them small you don't have to drill as big a hole in the plate and bring the gross area down to a really poor net area. That has side effects number one is is if you have a bolt inside of a steel plate with this thing having a tensile or compressive stress of 120,000 psi when the bolt presses against the side of the steel plate and that didn't mean those had negative side effects they just have side effects the failure will always occur in the plate in bearing because the plates what 50 ksi maybe 80 ksi and this sucker here is 150,000 psi or 120,000 psi you know the failure will occur actually in the plate some people get a little careless when they'll say okay and the bearing stress in the bolt well that's true the bearing stress in the bolt is the same as the bearing stress in the plate but the plate is always the one that you'll be working with always the one you'll be checking here you'll have a load on the plate as always you'll have to check the gross section area net tension area gross tension area you'll have to check across the holes now that you're going to have to also start checking these bearing stresses you really need to know where that bearing stress occurs and in this case here the bearing stress is on this side of the bolt and it goes through the bolt and shear and then the bearing stress occurs on that side of the bolt and then that load turns from compression in the plate or it goes around the hole and comes out in tension and it comes back to the load p here you have p and p over two in the two plates here the bolt gets cut once drawing a free body of just the top half you have the load on the top of the bolt and you have the shear inside of the bolt so that's really v and here you have a bolt in double shear so here we go first failure resulting one mode from excessive tension shear bending in the parts being connected say no more say no more he said it all gross area effective tension net area block shear anything that failed it before still has to be checked now now then the new things to be checked would be shearing the bolt itself and the resulting bearing stresses caused by the bolt in the plate failure of the connected part because of bearing exerted by the fasteners on the plates hole is going to be slightly larger than the fastener otherwise you'll never get it together contact between the fastener and the connected part will exist over approximately half the circumference of the fastener that's right around in here that's one diameter around the around the bolt now you say well it doesn't look like that to me it looks like a point contact yeah but when you put the load on it that we're getting ready to put on it you're going to find a big old gouge in this plate when you really stop at the limit and that deformation is permitted to be a quarter inch and by that time this steel plate will have wrapped nicely around that bolt regardless of what you think the cross sectional area is if you want to do the same thing your peers are doing the diameter of the bolt is the pressure area between those two plates and you will take the bearing area as the diameter of the bolt not the hole multiplied times the thickness of the plate that would be how much surface area is in contact and even that isn't true because that steel as you know is horribly stressed you say all right on up to f sub y well the truth is it's probably going up past f sub y you say well okay f sub u and i say well the truth amount is probably past f sub u so how can you get past f sub u well it's like jello you can't put a lot of pressure on jello unless you put it in a cylinder and put a plug down in there that's sealed nicely then i say how much force can you put on jello you say just about any stress you want it's not going anywhere first thing's going to fail is the tube is going to fail in tension you put enough load on it well all of this jet jello all of this steel is underneath a washer and the head of the bolt and so is the area really the diameter of the bolt no not really is it really uh it can't squirt out of there until it gets out from underneath the head and so probably what we're going to have to do is talk to the theory of elasticity people and they say you're nuts and so then we're going to have to go talk to the experimentals and they say go test every size bolt known to man or lady tell me uh for different thicknesses for different distances from the age this that and the other the whole nine yards how strong is that because i need to have a rational way to design these buildings when they tell you how much stress you can put on a bolt in bearing and they got a weird number like 1.2 2.4 that's the reason why but you still have to come up with the starting number and then work from there the area in bearing is that diameter of the bolt times the thickness of the plate nominal strength is going to be equal to the diameter of the bolt times the thickness of the plate times f sub u and they'll give you some factors to go with it i was using the previous one just for all the pictures i got on there same page in your text now other things can happen when you drill the hole in here if you drill the hole pretty close to the edge it's possible to pull this little plug of steel out in front of the in front of the bolt or if you keep it back here quite a ways then you still may pull the little plug out but if you put it back in here i just don't think there's any way you're going to pull the little plug out i think it's going to break across here and then you say well it's not going to break across there because for this hole right here this plate got to be this wide so it's not going to break across there and so i'm going to have to tell you what else could limit your strength when this thing gouges about a quarter of an inch down into this plate things have deformed badly enough that i insist quit so you have a limit based on the little shear plug here l sub c that's called l clear times t in shear and that'll be times two because there's one on both sides not to be exceeded by the number that is reached experimentally and we can tell you what that is uh when you get about a quarter of an inch now the research council on structural connections they're the people we depend on for boats they do all the boat research they do all the boat numbers and we take their numbers and we stick them in our specs by being an aspect that means they're in your city code or your state code or your navy code the strength of this thing in shear this little plug you're going to pull out uh uh i'm not sure what do you think at point six came from what is what's this right here all about that's right it's the shear ultimate why because the tension ultimate in steel is always about six tenths of that number always is the shear ultimate and therefore this number right here could also say f sub u v but there any such thing as f sub u v nobody would know what you're talking about because it's always based on tension ultimate or tension yield six tenths times that number of the corresponding shear ultimates are shear yields six tenths is the shear fracture stress because it's a u of the connected part l sub c is a clear distance from the edge of the hole say there's a little more steel here they don't let you count it they evidently didn't work out that well in test gotta go from the edge to the edge of the plate is the thickness of the connected part here is the bolt people boat council rsc s here's their address w of w dot bolt council dot org and you want to see their code or their specs here the specs for structural joints using high strength bolts the reason i went to see what it was is because segui here says we're going to base all our stuff on 2009 that's getting kind of long of tooth i was i was thinking okay this is a either my old book or your old your book hasn't been updated yet or something 2009 it's a pretty long time not to have something updated it says right there you want to see the current specs 2009 they say they're still good nobody's done anything since that time that was gonna give you a whole bunch of extra strength at no cost or at any cost now one of the limits will be shearing these little plugs out and one of the limits will be gouging this little plate to a quarter of an inch equations for both and you'll find out which one controls just by checking the equations here's one where the little plug sheared out and this one's where the gouging of the steel to a quarter inch limited this load here's one little too close to the end but they're not going to let you get that close to the end but it is pretty much trying to shear that plug out here's somebody who doesn't know what they're doing but it's okay that's what he wants if he says i don't have any choice well you get a little strength out of this l clear and this l clear they probably won't let you do that because once you put the nuts on there or the heads in the holes you won't be able to get a wrench on it so they're going to make you keep these centered line distances some limiting distance apart so here's our strength here is our little plug a b c d is seen from the top there's a b c d here is the thickness right here is the thickness of the plate there's the shearing surface area of the plug there's your nominal strength you're going to have to have to hit that with a fee stick to bring it down to things that i can talk about and therefore six tenths f sub u times l clear times t l clear times t i believe your book shows a lower case l you know why they would change cap l to lower case l in the specs and therefore force him to redo the book i don't know but i'm not about to do redo all these pictures so that's so that's little l sub c l clear there are two of them and so the nominal strength would be half on this side there's this side so r sub nominal is 1.2 f sub u l sub c t there's your equation number there's the page where the specs tell you to find it this needs to say i think l clears the distance from the edge of the hole well now that's a little bit of a question the edge of the hole or the edge of the hole it's only the edge of the hole in the direction of the load they will not let you put this too close they say something like the edge of the hole in all directions they mean this way and this way must not be too close but when we're talking strength of these little plugs we're talking the edge of the hole and the end edge of the plate not the side edge the true failure surface when they really pull these little plugs out they occur kind of at an angle but we just assume straight line here is half of the resistance half of the resistance that's l clear l clear will equal to l to the end minus the hole size over two interestingly the hole size is equal to the bolt size plus one sixteenth because that's the size drill you used that's it and you said i don't understand earlier you told me that i messed up all the steel around the hole to the tune of another sixteenth of an inch wouldn't even let me count it yes that was true and when you pull on the plate still that steel has really been hurt and i don't want you counting that extra sixteenth of an inch but we're talking about bearing stresses and this little plug coming underneath here and those bearing stresses are underneath uh nut and underneath the head of a bolt and so i don't really care if you have messed up i care that you drilled out but i don't care if you messed up that extra sixteenth because that's part of the steel that's going to get messed up to the tune of a quarter inch anyway and it's not going anywhere so this is the size of the hole that you use in calculating these little dimensions across here in your bearing stresses whole strength you already had that on a previous page now then he says not to be exceeded by a limit of some magic constant times the same bearing or times the bearing area bearing area times f sub u that c is a constant he's ashamed to even admit it he's afraid you're going to ask him why it's so big well i already told you why it's so big uh uses equation seven one for bearing strength subject to an upper limit given by seven two if excessive deformation as a service load is a concern that's at a service load and he usually is c is taken as 2.4 wow 2.4 times what you and i would have first off just said it ought to just be you know some number d times t that's it you crushed it d times t is the area times f sub u 2.4 now i don't mind this because we do it all the time we say go ahead and calculate something to make sure it's not any bigger than this the truth is it's two completely independent things and i bet you what this two are doing i bet you that one of them's texting the other one is watching them both one of them types and then the other one types and then the other one types and i say why don't you just talk and you say well we talk you get mad at us yeah okay go ahead good enough but these are two cops they're really different people they don't even talk to each other i mean this should be less than that that's true but if you calculate this then this must be less than that so basically you have two limit states you check the two limit states you take the lower of the two clear distance l sub c is in the direction parallel to the applied load from the edge of the bolt hole to the edge of the not sure that's an adjacent hole or to the edge of the material that's that'll i don't like those words to the end edge of the plate is it is material we're always talking about the distance to the end of the plate that's this way not this way now like i say max seems like it ought to be just the area times the ultimate because that's what it fails at where you get the 2.4 again here you got this washer here you got this liquefied steel and it's trying to get out and when it finally once i guess it can kind of bend up underneath this plate it will start failing stop picking up load but until then it just can't go anywhere probably long before that would happen anyway you've reached a quarter inch of crush in the plate and that's the limit now it's set to set with that 2.4 the old days the whole size for tension was diameter of the bolt plus 16th fit plus a 16th damage now then the h that you're going to use for bearing stresses going to be diameter of the bolt plus only the fit thing i use this whole page for was figures has the same equations as i just showed you here's one this is the h we were just talking about diameter of the bolt plus a 16th only dimension of this you need for the calculation how strong is the little plug that's being pulled out l sub c would be l to the end there's l to the end defined from the center of the bolt to the end of the plate minus half the whole diameter this one on the other hand is l sub c here is the dimensions i would give you i would tell you that this is four inches from there to there you need to calculate this so you would take four inches you would subtract half of the drill size which is a whole size minus half of the drill size which is the whole size not including damage and that would give you the l sub c that's the clear length had another one back here same thing this one would have three inches with a whole size on both sides subtracted this one would be six inches whatever i said minus two hold die two hole radiuses are one hole diameter and then this one right here is going to be l to the end minus only a half of a whole diameter that would be the length of this line same thing this is a little more noted this came from the shear load that you can permit on the plug of the plate this came from the crushing load on the plate between the bolt and the plate four pictures in case you don't understand you say understand understand here's the little plug that's being pulled out a b a b d e there's what you see looking at it from the top a b d e underneath the supreme numbers there's your little failure plane two of them bolts you can buy them with them threaded to the head they don't really get threaded quite that far there's there's a shank down in here little little space they're threaded as high as they can and when you install it the threads are in included in the shear plane they say in stands for not excluded i don't i don't like that it's a negative negative that i'm not sure what it means i see if they are here we go this is a good one the threads have been purposefully excluded from the plane of shear and as such there's more area on the bolt so i understand x meaning excluded from the plane of shear and if it's not that then it's in because it's not that it's this i don't know i just like included and excluded your choice how you remember it why the difference because this has pi d squared over four and this does not have pi d squared over four see how much smaller the root area is across there i'm sorry now see looking at the bottom of this boat right here and here's what it looks like right there and here here you see the threads down in here down in the bottom now then i understand that you see the peak of the threads here but the root of the threads are down in here and if you're going to shear it across the roots and you got to get a pi d square over four where the diameter is equal to this diameter minus the distance from the peak to the root on two sides so you have much less area in the root area than you do in the original bolt as a matter of fact it's right at this number is right at eight tenths of the bolt before you tinkered with it with that gum thing putting threads on there no the threads are excellent see the see the two plates you see how they're being pulled you see how the plane of shear is right here the did you see any threads in there they were excluded when this plate shears on this plate and it shears right across here did you see any threads were you shaking your head no they're right in the middle well all right if this if this bolt right here before it starts getting threaded if this diameter is one inch what's the area one inch some thickness no it's pi d squared over four it's these are round bolts that's the trouble you're used to seeing square bolts around the bolt it's a pi d squared over four now then if you cut some of that metal out of there such that this goes as far as here and this one goes as far as here and this new dimension is minus point oh six minus point oh six the cross sectional area is pi new smaller diameter squared over four now this is the shear plane this okay here's the shear plane and the threads didn't get up there yet maybe i want to take a few threads out oh no no no that's a those are bearing stresses now i'm talking to you about shearing the bolt now these the this bolt is still bearing against that full thing over there diameter of the bolt times the thickness of the plate and down in here even though there are threads in there that's okay we consider that these things here will fill up those threads and they do it does as you really mash that steel into the bolt i'm sorry i would guess i didn't mention what i'm looking for i'm talking about the thread area being cut or not cut all right and more pictures with bearing stresses and definitions of l sub c the load and resistance factor design since it is a braking situation we will be using a resistance factor of point seven five so when all is said and done he had done have it might have it on the previous page i didn't notice now well he'll get to it those nominal loads that we were calculating a minute ago will be reduced to point seven five of that value and he talks and he talks and he gives you the equation i told you l to the center line that's right is equal to l is sub e minus if so that's an end that's his l to the end minus h over two that was your clear distance from this point from this point from shut up you're confusing me from that point to that point because the load's going that way we already talked about that we already talked about this already talked about that talked about that i don't throw anything away man i well i tried to retire last year went over there and i applied and they said you can't retire i said why this issue's never worked and that's what can i say all right so if you have something that looks like this it's an inch and a half that way and two inches this way don't be using the two and a half for your l clear this dimension here okay now this l sub e is the one this is the distance from the center line to the edge you'll notice he also lists this is l sub e and that's that's true it's an l to the edge but it has nothing to do with bearing stresses or anything else they will make you keep this bolt they don't want you putting the bolts like this that's just not permitted so they'll make you stand out l sub e but l sub e to the end and l sub e to the side don't have to be the same number at all just because they're both called l sub e to maintain clearance so you can get a wrench on there they'll require that the center center spacing of the fasteners in any direction no less than two and two-thirds the diameter of the bolt preferably no less than three you can live with this but you probably don't want to walk out on the job site when you're doing it because you may get a wrench in your face d is the fastener diameter minimum edge distance in any direction is given in a table it's a function of the bolt size a table here's the what is the page it's on and i've got one on 385 b and let's just take a quick look here is the spec minimum spacing in any direction he tells you minimum edge distance he tells you and he refers you to the table here's a typical table for a three-quarter inch bolt they don't want you anywhere near closer than one inch from the center of the bolt hole to the edge of any to any edge of the plate and the end are on the sides all right we'll start there next time yes sir did i not call gamble well you know maybe i just was that's when i talked and said you know i just realized why all these people weren't here quit looking at that not yours yes sir yes sir yes sir age of the bolts of that bolt sure the one i just showed sorry i can tell you what i got oh yeah no i don't know where that is yeah no way this way down towards the end thank you okay far you see this let's let's come over here where other people when i don't know about in the surface area in contact with the bolt is indeed unchanged no matter where the threads are okay i'm talking about the sheer strength of the bolt itself okay so when this plate moves to the left and this plate moves to the right this bolt gets cut just like with a pair of scissors yeah and it gets cut across its long axis i thought these alternated where you had the short side alternated that's that's true yeah i don't have well yeah i don't have it drawn real accurately no no no no because let me let me change it because i can i can do that uh you would be you would be correct that on this side this would be a high spot yeah okay i mean i just i just drew it yeah that's just kind of all right no no no watch here now watch here now here we go still gonna have to change now here is your cutting area okay do you agree number one you lost this i don't the area's got to be smaller because right now what you're cutting through is you're cutting through a low spot you didn't you didn't add anything on this side you just didn't reduce the diameter at that point right now they have two things one of them is called the root diameter or the root area and that actually goes from there to there it's listed it's listed in all the tables yeah so i was thinking there might be an angular shear right and then there's another one that includes one threads area now let me see if i without messing things up too bad if i can find that i think i can but we always consider the shear point right on that line no not really not really you get to include the fact your fact in in fact you get to include the fact that you are not only getting the minimum thing but you're getting a little more duty you have to cut yet when you cut through the whole thing you got to cut a thread someplace okay here it is in the table number one for a one inch bolt you have so many threads per inch that tension area is point six oh six the minimum root area is point five eighty seven and the gross area with no threads is point seven eighty five so you're going to be using not the one i told you inside thread inside thread but inside thread plus three plus a thread you'll be using this area here that is correct root to root absolutely all that shear line absolutely however i would not draw that i would tell you that i'm using a325 in bolts that means automatically the threads are included or i'd say we're using a325x bolts that would mean we're excluding that means that you would use either the shank area or the threaded area there see this plate going to the right see this plate going to the right on the double shear well okay it could be well there's no double shear here now see there's a single shear plane oh it would depend if this wasn't well this is a bolt this is how it's got a nut on the bottom side here there's no other plate if there was other plate i would show it now if you say well i was thinking maybe of this situation here that is indeed double shear and if i'm going to spend the money to exclude the threads then i would show you shank shank shank shank shank shank thread thread thread thread thread shank shank shank shank thread thread thread and i would say that's an in connection with the threads or excuse me that's a x connection where the threads are excluded from the shear if you said look you know keeping up with a bolt like that and trying to figure out where the threads are fully just thread the whole thing all the way to the top then that is an included and you must use the small area times two times times two no no no it's not going to show here or here it's going to shear here and not fail if you say it sheared here then i'm telling you didn't fall apart this piece was still connected to that where it's going to fail is when this thing gets pulled and it shears in double shear two times then it fails i don't deal with there are no defects in these bolts we don't permit such a thing and if there is a defect in that bolt you remember that's probably why you got that little fee on there that resistance factor if there's an effect in that bolt there's nine there's six other bolts in that connection i'll bet you that one's a little stronger and if you say well i think there's a chance they're all six defective that's why we put the fee on there to take care of the chance that every now and then it might happen very rare very rare okay okay all right good sure thing