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Moment Connection when Minor axis bending is large
8

Moment Connection when Minor axis bending is large

Moment Connection when Minor axis bending is large

(OP)
Dear Engineers,

I have got a Beam Splice to design, which has both major and minor Bending Moment (BM). Major BM is 138 kN-m (102 kip-ft), Minor is 30kN-m (22 kip-ft). Please see the snapshot below.



It is taken from RAM Connection Program. The minor BM has been included in the program, but it used only the Major BM.



What I want to know is, the weld shown here for Major BM design, will it be adequate for Minor BM too? or Does it require further checks?

Thanks.

RE: Moment Connection when Minor axis bending is large

The plate takes the compression solely after the weld to the next weld for the weak axis moment, as such extra checks are advised not only on weld length but distance required.

http://www.nceng.com.au/
"Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning."

RE: Moment Connection when Minor axis bending is large

(OP)
rowingengineer,
I did not understand what you meant by this.

Quote:

The plate takes the compression solely after the weld to the next weld for the weak axis moment

RE: Moment Connection when Minor axis bending is large

Yes, I would check the connection plates, and weld, for minor axis bending.

RE: Moment Connection when Minor axis bending is large

(OP)
That would be helpful. Thanks.

RE: Moment Connection when Minor axis bending is large

If major and minor bending moments are concurrent, you can calculate an statically equivalent flange force to design the flange plate and weld. It can be calculated as:

Puf = Pu/2 + (Mux/(d + tp)) + 4Muy/bp

Where:
Pu = Beam axial load (if any)
Mux = Major bending moment
Muy = Minor bending moment
tp = Flange plate thickness
bp = Lesser flange plate width

I think this is a reasonable conservative approach, especially for the design of the weld.

If you want to design the splice using RAM Connection, then you must apply the major bending moment (Mux) in combination with an equivalent axial load equal to: Pue = Pu + 2*(4Muy/bp)

Hope this help!


RE: Moment Connection when Minor axis bending is large

We are not told the size of the beam. I assume that the flange width is 8" so that field welds will all be downhand. The weld to the top plate is along each side and each end, shown by the thick yellow line. The weld to the bottom plate is along each side, but if the weld is to be downhand, presumably not on each end.
Edit: Sorry, I used the wrong moment. Ignore blue highlighted text. See red text below.
For a minor axis moment of 138 kN-m and a width of 200mm, assuming only the side welds to be effective, the force transferred between beams is 138/0.2 = 690 kN, half top and half bottom. The weld length per beam is 100mm, so the force per mm of weld is 690/(2*100) = 3.45 kN/mm for minor axis bending alone. This will add to the major axis bending moment weld on one side and subtract on the other.

For a minor axis moment of 30 kN-m and a width of 200mm, assuming only the side welds to be effective, the force transferred between beams is 30/0.2 = 150 kN, half top and half bottom. The weld length per beam is 100mm, so the force per mm of weld is 150/(2*100) = 0.75 kN/mm for minor axis bending alone. This will add to the major axis bending moment weld on one side and subtract on the other.

I don't understand the computer output where it says "Weld size to bottom plate (1/16 in)", then shows an entry of 6 with no units in the column to the right. All other dimensions in that column are in mm, so I assume the default weld size is intended to be 6mm, substantially more than 1/16". Doesn't look like the specified weld is adequate for minor axis bending, let alone major axis bending.

I don't know why a WF beam is being used with such high minor axis moment. I don't like it, but perhaps there is a valid reason. I would certainly question the weld churned out by the computer. I still don't like it, but it's not as bad as I first thought.

BA

RE: Moment Connection when Minor axis bending is large

I usually take pause whenever the program doesn't allow input of a certain force, because often the developers have spent 100's of hours developing the program for each connection and have some valid research to back up their decision to exclude the allowance, but sometimes it seems that they just run out of time, or get lazy, and don't add certain functions. I just checked RISA connection and it doesn't include weak axis moment checks on this connection either.

I've never seen this detail used for significant weak axis moment, but like others have said the weak axis moment should be converted into a triangular force distribution on the flange plates, max compression on one side, max tension on the other. Additional design checks are basically just checks for the weld and weld base metal, with tension/compression from weak axis moment added to tension/compression from strong axis moment. (maybe flange plate buckling, but I doubt it with that short of an unsupported length).

RE: Moment Connection when Minor axis bending is large

BA,

The minor axis bending is 30 kN-m (22 kips-ft), but can be concurrent with the major axis bending, which is 138 kN-m (102 kips-ft), as noted by PROYECTOR.

RE: Moment Connection when Minor axis bending is large

retired13,

Yes, thanks. I have edited my previous comment.

BA

RE: Moment Connection when Minor axis bending is large

(OP)
Thanks Proyector, Could you give me a reference on that formula to check out in depth?

BAretired, Thanks for your analysis. Flange size is as you guessed. Weld size is actually 6 of 1/16 inch = 6/16*25.4mm = 9.5mm. The plate lengths are actually 200mm in each side of the separation point. so the force per mm weld is 150/2(200-2*25)=0.5kN/mm. 25mm is the setback from the separation point to the start of weld. Anyway, I am not much good at undrstanding weld strength. I need to go books.

MegaStructures, Yeah, it is very disappointing. At the time input, program takes all inputs, but when utilizing the data, its not considering one or two data, which someone might think the program to have taken into consideration, but may result in bad situation.

Thanks all, give me some sources of small readings in this regard, so that I can do it manually.

RE: Moment Connection when Minor axis bending is large

@All
As the minor axis momemt is 30kn-m .It will be divided between the top and bottom flange i.e each flange will resist 15kN-m of load. Thus the force in the flange will be 15/0.2 = 75kN.
Thus force in weld along lengtb 75/200=0.375kN/m
Also i will result in formation of couple like shear .Thus force in weld along width =75/175= 0.428kN/m
Is my understanding correct?

RE: Moment Connection when Minor axis bending is large

@BARetired As u said it will be added on one side amd subtracted on the other.My understanding is if my top flange in in compression amd due to minor axis moment my one side of flange is in compression and other in tension thus for one side we will be subtracting and for other we will be adding.Is my understanding correct?

RE: Moment Connection when Minor axis bending is large

Sammy,

FYI on weld design (for My only. Note that minor axis shear, Vy, needs to be added, if present). You shall also check the strength of the connection plate for the minor axis bending and shear.

RE: Moment Connection when Minor axis bending is large

@retired13 So is my understanding correct.Our drawings are matching.
But I have one doubt.When calculating the force for the weld we are adding the major axis bending momemt force to get the critical force for weld.
In case of simple I Builtup beam we design tge weld between web amd flange for only shear force that is acting on the beam and we never consider tge major axis bending moment force for weld calculation.
Why?

RE: Moment Connection when Minor axis bending is large

The web connections needs to be designed for the moment caused by eccentricity of shear (likely not present here), but the major axis bending is assumed to be taken up by the stiffer flange connection. Always think about which part is stiffer and will carry the load first.

I'm confused is Sammy345 and OP the same person on different accounts?

RE: Moment Connection when Minor axis bending is large

@Megastructures I just saw the post and wanted to know the concept.I am only handling this account.The OP is some other person

RE: Moment Connection when Minor axis bending is large

Got you. I thought Maybe Kevin Durant took up engineering.

To expound on my stiffness comment. As the member rotates the flange connection, farther away from the N.A., will take up force and stop the beam from continuing to rotate. At this point the web connection will have rotated far less, again due to it's relative location to the N.A., and will not develop significant stress from the rotation.

RE: Moment Connection when Minor axis bending is large

@ Megastructure I am talking about forces on weld and you are talking about stiffness.

RE: Moment Connection when Minor axis bending is large

Sammy,

In this case, the minor axis bending becomes torsion on the half connection plate, so it is additive to the stress due to major axis bending (Fw = Mx/d), as both resulting in shear in the weld. Note that the shears are to be added together as vectors if they orientate in different direction/axis. Also, do not substract shears in opposite direction, but to use a single weld size for the largest force in the weld lines.

When design the flange to web connection in a built-up section, we consider shear (V) only, because moment is the integration of shear force, that is the source of deflection and curvature, for which the flange and the web have to be built in accordance to the rules of compatibility and stress equilibrium. I hope this helps. But I think BA/KootK maybe able to provide a better/clearer explanation.

RE: Moment Connection when Minor axis bending is large

Quote (Sammy345)

I am talking about forces on weld and you are talking about stiffness.

It's almost as if stiffness and force are directly related by some kind of.. law?

Hookes law --> F=Kx (force = stiffness times displacement). The more your material stretches and the stiffer it is the more force it carries. The flange connection is stiffer kflange>kweb and it rotates more (the flange is farther from the N.A. as stated previously), so x is greater for the flange. If kflange>kweb and xflange>xweb ==> fflange>fweb

Hopefully that helps you see how the two are related.

Edit it's possible I misunderstood your original question as well.

Quote (Sammy345)

n case of simple I Builtup beam we design tge weld between web amd flange for only shear force that is acting on the beam and we never consider tge major axis bending moment force for weld calculation.

You're talking about a built up I-beam made from plates and want to know why there is no moment calculation for the longitudinal weld between the web and flange? I originally thought you were asking why moment wasn't considered in a web connection.

RE: Moment Connection when Minor axis bending is large

Sorry that my response has caused confusion. My post for weld design/check was meant to assist OP (Newbie), but mistaken Sammy as the recipient.

RE: Moment Connection when Minor axis bending is large

I'm curious, do engineers generally consider the difference in strength between longitudinal and transverse fillet welds as shown in Sammy's and retired13's sketches?

Dik

RE: Moment Connection when Minor axis bending is large

dik,

I do consider weld stresses in all three directions, and combine them as vector fields. But I wouldn't reject simplification for certain cases.

RE: Moment Connection when Minor axis bending is large

@Megastructures Right. In case of Built Up I sections we only consider shear .But for OP's connection we are considering major axis momemt as well for weld design .Why?
@retired13 I am still not getting

RE: Moment Connection when Minor axis bending is large

@retired13 If I have simply supported I Beam(Built Up Section) with udl and a concentrated major axis momemt at center.I would still design tge weld between web amd flange for shear force only.But for OP'case why will we check for both major and minor

RE: Moment Connection when Minor axis bending is large

Sammy,

I think you can use minor axis shear, Vy, to check the weld for the connection plate in OP's case. But it can be misleading, as the minor axis moment causes an localized deflection/curvature on the connection plate, that is to be brought back to be in conformance with the shape of an continuous beam without the cutoff. Note at the gap between beam segments, the effective cross section consists of only the top and bottom connection plates, the beam continuity/rigidity is lost (parallel to Maga's comment).

RE: Moment Connection when Minor axis bending is large

Quote (Sammy345)

As the minor axis momemt is 30kn-m .It will be divided between the top and bottom flange i.e each flange will resist 15kN-m of load. Thus the force in the flange will be 15/0.2 = 75kN.
Thus force in weld along lengtb 75/200=0.375kN/m
Also i will result in formation of couple like shear .Thus force in weld along width =75/175= 0.428kN/m
Is my understanding correct?

I made the same mistake. The plate length is actually 400mm top and bottom (200 lap to each beam). Force in weld (to each beam) = 75/200 = 0.375kN/m is correct.

There is no "couple like shear" across the beam. The applied moment results in side shear only.


BA

RE: Moment Connection when Minor axis bending is large

Sammy,

Wish you can pick out the design forces for the two cases shown below. 1) A cover plate on the beam, and 2) a connection/continue plate on the beam segments.

RE: Moment Connection when Minor axis bending is large

In the following, I am ignoring the weld across the beam in the top flange. It is probably not a good idea to weld across the beam flange as it may weaken it, so assume only side welds top and bottom.



BA

RE: Moment Connection when Minor axis bending is large

Quote (retired13)

In this case, the minor axis bending becomes torsion on the half connection plate, so it is additive to the stress due to major axis bending (Fw = Mx/d), as both resulting in shear in the weld. Note that the shears are to be added together as vectors if they orientate in different direction/axis. Also, do not substract shears in opposite direction, but to use a single weld size for the largest force in the weld lines.

I disagree with the orange highlight. I believe that minor axis bending remains bending in the top and bottom plates.

I agree that shears should be added as vectors, but in this case, I believe the direction is the same.

Subtracting vectors is the same thing as adding but paying attention to sign. It's okay to do that, but I agree that changing weld size would be confusing for the welder and could result in error.

BA

RE: Moment Connection when Minor axis bending is large

BA,

I consider Mw is the same as torsion (rotate about the vertical axis), so the weld design fw = Mw*r/Jw.

RE: Moment Connection when Minor axis bending is large

retired13,

I don't agree. J is not involved. Torsion for a plate oriented horizontally would be a rotation about a horizontal axis.

Mw in your sketch produces bending stresses Mw/Sy at the middle of the plate (each edge)
where Sy = tb2/6, t being thickness and b being width of plate.

BA

RE: Moment Connection when Minor axis bending is large

Think again. You have two tasks here - design the weld and check the plate. I do agree you can simplify the weld design uses Fw = Mw/b for the longitudinal weld lines. But for this case, the design was already done for the major axis bending use 3 sides weld, so I use equation of torsion to produce more tolerable weld size to add to the existing, rather than over simplification and overly conservative.

For the plate bending stress, yes, f = Mapp*y/I as usual.

RE: Moment Connection when Minor axis bending is large

retired13,

This is a case of biaxial bending. There is no torsion that I am aware of.
I don't know how to determine the expression r/Jw or in fact, what each term means.

BA

RE: Moment Connection when Minor axis bending is large

A side note on how I distinguish moment and torsion in this situation - it is a moment if normal stresses are the concern; and it is a torsion, when shear stress is required.

RE: Moment Connection when Minor axis bending is large

I vote with BARetired, in the original post this was described as strong and weak axis bending, no moment around the member length axis was described or discussed.

This is case of running down a rabbit hole of confusion and sloppy naming. Torsion in this case is NOT a useful concept.

Jim

RE: Moment Connection when Minor axis bending is large

Rotation can occur at any axis. In this case, due to symmetry, we can image half of the plate will be rotate freely due to the internal moment, thus the need of the weld at the end to hold the plate in place. And the weld is subjected to the shear stress produced by torsion.

RE: Moment Connection when Minor axis bending is large

Am I the only one that uses tb^2/4 for plates?

Dik

RE: Moment Connection when Minor axis bending is large

The connection plate weld design method is the same as the beam web connection with bolted ends. Both subject to torsion as the applied force that would cause separation if without. Hope this makes sense.

RE: Moment Connection when Minor axis bending is large

@BARetired Firstly this 30kN-m is applied to the whole beam cross section.Thus Top flange will take its share of 15kN-m and bottom flange will also take care of its 15kN-m.
For tge purpose of understanding let 30kN-m be applied to top flange only. Then Why are you dividng the force to side weld? Like you said 150kN or 75kN each side weld.(My= 150x0.2=30kN-m ; 75x0.2=15kn-m).The first one in bracket is correct as we get the same applied minor moment while the other one is incorrect).So it should be 150 kN only to each side weld and not 75kN.Am I missing something?
I did my earlier calculations considering only 15kN-m to top flange only.
Also why couple like shear would not be generated .The forces are actimg on the flange on opposite direction due to minor axis momemt.Suppose in clockwise direction .To maintain equilibrium tghe other two forces must be genrerated in anticlockwise direction like it happens in shear. Can you please expain?
And why are u adding major axis moment to weld design ?
We don't do it when we are designing weld betwwen web and flange of Builtup I section .Why are we doing it here?

RE: Moment Connection when Minor axis bending is large

Quote (dik)

Am I the only one that uses tb^2/4 for plates?

That is the plastic section modulus, dik. You are not the only one to use it. I would use that for strength calculations if that was the only moment acting on the plate, but if we want to know the maximum stress in the plate as a result of My on the beam, we must use elastic section modulus. The minor moment My can't engage the plastic section because the plate will be stressed simultaneously by the major moment Mx.

BA

RE: Moment Connection when Minor axis bending is large

Quote (Sammy345)

For tge purpose of understanding let 30kN-m be applied to top flange only. Then Why are you dividng the force to side weld? Like you said 150kN or 75kN each side weld.(My= 150x0.2=30kN-m ; 75x0.2=15kn-m).The first one in bracket is correct as we get the same applied minor moment while the other one is incorrect).So it should be 150 kN only to each side weld and not 75kN.Am I missing something?
I did my earlier calculations considering only 15kN-m to top flange only.

You were correct to use 15kN-m for the top flange only. The bottom plate takes the other 15 kN-m. That means the weld on each side of each plate takes 15/0.2 = 75kN as a result of My.

Quote (Sammy345)

Also why couple like shear would not be generated .The forces are actimg on the flange on opposite direction due to minor axis momemt.Suppose in clockwise direction .To maintain equilibrium tghe other two forces must be genrerated in anticlockwise direction like it happens in shear. Can you please expain?

The couple like shear is not generated unless the plate is also welded to the ends of the top flange of each beam. It is true that an end weld would contribute slightly to resisting My but not as a couple the way you envisioned. The couple would need to be applied to both beams. Furthermore, welding across the beam flange is considered bad practice because it weakens the beam. It can't be done on the bottom plate without overhead welding, so I considered only side weld and no end weld for both plates.

Quote (Sammy345)

And why are u adding major axis moment to weld design ?
We don't do it when we are designing weld betwwen web and flange of Builtup I section .Why are we doing it here?

Yes we do do it between web and flange, but we have half the length of the beam in which to do it. When you calculate the shear flow in the weld, you use the expression VQ/I. and if you add that up between support and maximum moment, you will find that it is identical to the flange force at maximum moment. In this case, however, the flanges of both beams terminate at the splice. The splice plates have to carry the entire major moment Mx with a lap of only 200mm on each beam. To get the force into the plates, you need plenty of weld in that short length.

BA

RE: Moment Connection when Minor axis bending is large

retired13,

You are talking about a transverse weld. I believe it is considered bad practice to weld across a flange as it weakens the beam. It can't be used on the bottom flange without uphand welding, so I used only side welds to carry both major and minor moments. That makes welding for both plates similar.

BA

RE: Moment Connection when Minor axis bending is large

I would instead use the term 'moment in the plane of the weld group' instead of 'torsion' in Retired13's sense. And polar moment of inertia of the weld group instead of Jw. The numbers are the same though.

BAretired, how serious is welding across the flange? What about stiffeners which have two cross-flange welds at close spacing?

Dik, I don't treat longitudinal and transverse welds as having different strength.

RE: Moment Connection when Minor axis bending is large

Technical terms often are exchangeable, important are the method and results. The difference been, when conservation brings up bending moment and stress, we are likely immediately linking it to the normal stress, f = M*y/I; on the other hand, when we see a calculation expresses stress as, f = M*r/Ip, we will link it to torsion, even though the presence of moment abbreviation.

RE: Moment Connection when Minor axis bending is large

Comparing to BAretired's numbers from 30 Aug 18:02: BA gets 213kN/200mm = 1.065kN/mm weld stress. This is an assumed uniform longitudinal stress

Retired13's elastic analysis gives 1.011kN/mm peak stress at two points (either end of the 'additive' weld). The direction is a little oblique to the weld direction. This is based on the same two parallel welds as BA's analysis. I expected this method to give a higher stress tbh. I think what I overlooked is that the lever arm for minor axis bending resistance is bigger for the elastic case which overcomes BA's averaging along the weld length. The averaging effect is smallish for this geometry and then reduced further because the major axis stress dominates and the peak minor axis stress is at 45 degrees.

RE: Moment Connection when Minor axis bending is large

(OP)
Dear all,
Forgive my silence being OP. I don't understand a lot of things you are talking about which I need to learn to talk about.
Anyway, you may continue the discussion since it may be of benefit to me or someone else.

RE: Moment Connection when Minor axis bending is large

Newbie,

I suggest to open up an engineering mechanics textbook to review the equations for shear stress, normal stress (tension/compression), torsional stress and shear flow, then you know what has been discussed here.

RE: Moment Connection when Minor axis bending is large

(OP)
I understand those stresses. Maybe I need to check out some weld design examples.

RE: Moment Connection when Minor axis bending is large

Quote (The minor moment My can't engage the plastic section because the plate will be stressed simultaneously by the major moment Mx)


Might be missing something here... doesn't it just change the size of the rectangular stress blocks so that resultant is equal to the Tf and Mf? The reduced plate still has its tensile and flexural capacity.

Dik

RE: Moment Connection when Minor axis bending is large

2
You can download the "Design of Welded Structures", by Omer Blodgett, on the linked site. When prompted to "upgrade", don't, select the tap says "this paper only" instead. It is free. Link

RE: Moment Connection when Minor axis bending is large

Quote (Dik, I don't treat longitudinal and transverse welds as having different strength.)


I don't either usually, a matter of convenience, only. I don't know if I'm losing some significant value by ignoring them.

Dik

RE: Moment Connection when Minor axis bending is large

dik,

I think most people, me included, ignores the additional strength provided until desperate needs.

RE: Moment Connection when Minor axis bending is large

Quote:

I think most people, me included, ignores the additional strength provided until desperate needs.

The plate is automatically about 50% thicker... big change.

Dik

RE: Moment Connection when Minor axis bending is large

Quote (steveh49)

I would instead use the term 'moment in the plane of the weld group' instead of 'torsion' in Retired13's sense. And polar moment of inertia of the weld group instead of Jw. The numbers are the same though.

BAretired, how serious is welding across the flange? What about stiffeners which have two cross-flange welds at close spacing?

I think it is a precaution for field welding in situations where the structure may be compromised by weakening part of it by welding. Although not specifically stated, these welds are clearly field welds as evidenced by bolts in the web. We do not know where in the structure this splice occurs, so it may not be serious at all. It seems like a daft sort of splice to me, but who knows, maybe there is a good reason for it.

The second reason for avoiding transverse field welds is the overhead welding which would be required on the bottom plate. It would be more economical to make the plates a little longer and put the weld on the side.

However, if we are determined to weld across the flange, I would not consider that weld as contributing to My where it is only marginally useful. Instead, I would deem it to be resisting Mx where it is 100% useful.

You are correct about the weld group, steve. If there is to be a 'U' shaped weld on each beam, the stress will be sort of a torsion on the weld group. There is no torsion on the plate, which is what I first thought retired13 was claiming.

BA

RE: Moment Connection when Minor axis bending is large

Quote:

You are correct about the weld group, steve. If there is to be a 'U' shaped weld on each beam, the stress will be sort of a torsion on the weld group.

Thanks BA for clear me up :)

RE: Moment Connection when Minor axis bending is large

Quote (NewbieInSE)

Thanks Proyector, Could you give me a reference on that formula to check out in depth?

There is no reference, just statics assuming a plastic stress distribution in the flange plate due to minor axis bending. However, there is a quite similar approach for bolted column splices in Tamboli's book "Hand Book of Structural Steel Connection Design and Details".

The equivalent flange force approach is just a design simplification that may be quite conservative for the weld design (it works better for bolted splices).

For the weld design, I would ignore the transverse weld segment as suggested by BAretired. You could design each C-shaped weld group using the instantaneous center of rotation or any other method, but since you only have C-shaped welds at the top flange, it's not really worth it.

I find the following quote very relevant to this discussion:

Quote (Bo Dowswell)

A good design model is one that produces sufficiently accurate results in a reasonable amount of design time. In many cases, connection design time can be greatly reduced if the designer recognizes that the calculations are not always required to be theoretically correct. Over-complicated, theoretically correct design models can cost more money in engineering time than they may save in fabrication and erection costs. When more than one design model is available, the connection designer must decide which one to use.

Attached is a comparison between the equivalent flange force approach and a more theoretically correct design model. The plate acting stresses are calculated for comparison purposes only.









RE: Moment Connection when Minor axis bending is large

Sorry, there is a little errata in the above calculations. The modification is indicated in red...



RE: Moment Connection when Minor axis bending is large

Quote (retired)

You can download the "Design of Welded Structures", by Omer Blodgett, on the linked site. When prompted to "upgrade", don't, select the tap says "this paper only" instead. It is free. Link

This is by far one of the best structural steel design books ever published, thanks for sharing!



RE: Moment Connection when Minor axis bending is large

You are welcome.

RE: Moment Connection when Minor axis bending is large

Quote:

who knows, maybe there is a good reason for it.

I seem to recall that there is some evidence of a triaxial stress state induced.

Dik

RE: Moment Connection when Minor axis bending is large

Quote (This is by far one of the best structural steel design books ever published, thanks for sharing!)


I still have my '66 edition and I occasionally still use it... at the time, it was cheaper than dirt... like $10 or so if memory serves... about $1/lb. Only thing I missed was an index. Likely someone has put together a *.pdf file index over the years.

Dik

RE: Moment Connection when Minor axis bending is large

PROYECTOR:

Thanks... just turned this into an SMath sheet... keep up the good work.

Dik

RE: Moment Connection when Minor axis bending is large

dik,

Now the book has turned to 800 some pages monster... don't know how much has added in though.

RE: Moment Connection when Minor axis bending is large

It is an amazing book, and you can download all 837 pages on the internet in pdf format.

BA

RE: Moment Connection when Minor axis bending is large

Even the page numbers do not make it easy to determine the number of pages... With the *.pdf, at least you have a good idea...

Dik

RE: Moment Connection when Minor axis bending is large

I was going to order a couple of the books on Weld design from the foundation... but the shipping cost is greater than the books.

Dik

RE: Moment Connection when Minor axis bending is large

I've got them all. You'll find that much of the material is repeated unless you're looking at doing axles, machine bases etc.

RE: Moment Connection when Minor axis bending is large

By the way, in Ram Connection the column splice welded flange plate connection can be used to check for minor axis moments so you can turn ths problem on its side to get the relevant weld and plate bending checks.

RE: Moment Connection when Minor axis bending is large

@BAretired and retired13 Sorry I am replyimg late. Now I get it why it will not be a couple.I was thinking about it in a difgerent way.
Btw how Vy(Minor) will be 0.If a minor axis moment is applied on the flange then Vy will be generated as the ends of the beam connection will have to resist this moment. Also shear forces will come in flanges due to this Vy plus the major axis moment plus the axial due to minor axis bending.
As u said it is not a good practice to weld across a beam.But can you please explain in case of Vy ,the shear force that will develop in the flange will be in the form of couple.If we provide one side weld it has to resist both the couple.Otherwise I can weld across the flange amd my one couple will be resisted by both the welds.

RE: Moment Connection when Minor axis bending is large

@Sammy345,
Vy was not specified in the first post, so I assumed it to be negligible. If Vy is not zero, My is increased by approximately Vy*200. This would increase the weld force parallel to the beam, and in addition, would create a force normal to each weld of approximately Vy/4 in each half of each plate.

BA

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