How to Calculate the Demand on AND Capacity of a Weld
Вставка
- Опубліковано 23 сер 2024
- Learn how to determine what stresses are acting on your welded connections as well as how to calculate the capacity of common welded connections. Using the AISC manual in conjunction with my secret book Design of Welded Structures! Enjoy!
I’ve paid thousands of dollars to PPI and EET for structural depth classes and have failed the PE twice. I’m attempting again on Wednesday, I found your videos a little late in my studies but if I pass this time it is all thanks to you man. The way you explain the subject material in a fun engaging way makes all the difference! Keep it up and see you on the other side hopefully as a PE!
you can do it Armil! let me know how it goes
Thanks for the videos. Was wondering if there is a follow up video or similar that checks a the column for local failures due to the welds
Professor Kestava: Thanks so much for your superb videos with actual calculations along with the manuals. This is so educational! THANKS .... your the best. Yes you are truly a "professor" as I call you. CTF AIA
I knew you were legit when I saw Blodgett on the table! Great Video!
legoooooo - you know
Good stuff.
I like that you film the book you open to get the equations and info. Most problem-solving vids just reference the equation number from the CERM or AISC manual, etc.
Keep it up. Hoping you get more subs to keep the videos coming. I particularly like the "tips and tricks" vids along with the in depth design problems.
John thanks for the compliment and kind words! I'll keep pushing to get vids out to everyone!
I just want to say I love how you explain everything and back it up with code sections, etc. I'm an architect and have been providing my own structural design to all my projects since the 80's. I'm not so good with steel, but your video here encourages me to apply it or at least be able to review it as being accurate. I've been following your videos for a month now and wanted to say thank you! You are a fun guy to follow along with. Structural engineering is more fun now because I can follow you and apply it to my needs. Keep the videos coming and I may have to request some help in the future. Thanks Man!
I appreciate the kind words from an industry vet! thank you! and please do reach out anytime via my email on my channel or in any video description if you'd like to connect on a project your working on!
Excellent Video! Very helpful for intro into understanding the busy world of welding crap together. Side note: the pork chops cooking in the background were making me hungry
sizzle sizzle, thanks Matt!
@@Kestava_Engineering can I say again how excellent a video this is?? Asking for a friend
well explained. Need more like this.
appreciate it Sabbir!
Perfect example, hope get some in next exam.
ua-cam.com/video/vFDMaHQ4kW8/v-deo.html 💐
Best of luck!
useful and easy to understand , thanks
Glad it was helpful!
you´re great man thank you
you're great!
Great job man. Because of this video i get the omar's book and i learn more every single day. But i have doubt. The resultant weld force is not this:(Fv^2 + Fb^2)^0.5?
Awesome man. BTW the guy in the background is probably washing Friday night dishes.
LMAOOOOO
@kestava, What are your thoughts on a resultant force on the weld? i.e. Its not necessarily "fb + fv" you are checking against available strength, but it is "sqrt(fb^2 + fv^2)" .
Is the weld adequate because the 5.57K/in capacity > (Fb + Fv = 5.17K/in) OR because it 5.57K/in > Fb and separately 5.57K/in > Fv?
What if that W section was rotated 90 degrees and we still wanted to calc the shear weld capacity. Would now the flanges as the vertical welds only be used? Would the web be ignored if rotated as said to now be horizontal?
Is there a video explaining why vertical shear can only depend on vertical weld? Or can you explain why?
I've just been told it as a rule of thumb, but from AISC and AWS direction I believe you can design a weld for both directions. The quick reason is that the shear demand is carried through the web of the WF beam in this case, so the vertical weld to the web is the most direct load path for shear forces, where as the flange welds are a much more difficult load path.
Hi can you please do an example on how to design a moment connection? Like how to find the size and thickness of the triangular gusset plate and end plate at the joint of beam and column connection for practicing entry level engineer. Also, all type of foundation design shallow and deep foundation. Especially mat foundation first. I struggle to find good real live application example on this. Probably also go over how to design a simple 3 story residential building start to finish by hand calculation procedure step by step please so I can follow.Can you also share tips on how to connect formulas with real live applications. I can't seem to connect them.
The welding lenght yo take it as 1 in for comparison and its ok. I think in converting weld to line load by using tables its calculating for one side weld but in your example we have weld on both side for web and also flange. So I the value of welding line load should multiply by 2. Please if I have miss understanding revised what I said
Great Video! I have a couple of questions. When talking about which weld resists shear/moment, is there some literature on that? When learning under engineers at my company we've always used the full weld to resist shear and the full weld to resist moment using the welding design from "Steel Plate Engineering Data" by STI. None of us are structural engineers since we mostly work with ducting/piping/vessels but often require adding steel beams to supports things while we take out other pieces which require field welds similar to the example.
I was also curious if you could do a video on stitch welds/secondary welds as my current understanding of the matter is iffy.
Hi Scotty
1. as a rule of thumb - shear only transfers through the web of a W section. Its very difficult to get stresses to move out of the web and through the flanges, so we typically calculate all shear moving through the web weld.
2. moment can be transfered through a "force couple" between the flanges of the w section. ultimately moving through the flange welds as either a compressive force or tensile force.
3. you CAN perform calculations to resist combined shear and moment through the entire weld but we generally prefer to stick to the methods ive described as its slightly conservative and we dont have to worry as much about weird stresses moving through our connections to make things pencil out.
I hope this helps in any way! the blue book i mentioned in the video is honestly all i use for weld information! an AISC steel manual has literature about welds also.
Question: The weld capacity equation in Ch. 8 (simplified as 1.392Dl) is used for longitudinally loaded welds is it not? How can you check the flange welds with the same equation? If the flanges are in tension and compression, then the corresponding welds would be loaded transversely. Thanks in advance.
Great Question! Id say check out page 8-9 in AISC 14th edition and 16.1-117. you can conservatively take a weld strength of 1.0 regardless of load direction. but there are other options.
@@Kestava_Engineering Thanks for the response, keep up the good work.
Very helpful. Thanks
Can i apply the method of checking the suitability of a weld described in your video, if the load is acting in tension only, i.e. no shear or bending?
Yes!
You may need to check block shear depending on the elements geometry tho.
Will this work for flange weld demand? Turn the torque into a flange force couple. Do you think the welds or beam will experience additional stress because the flanges are not welded concentrically to the flange force, ie. only welded on one side?
144IN-KIP/(8)=18kips/4"=4.5k/in
Hi JJ, that's a great questions! honestly I believe the additional stresses are minimal in the case you mention at the flanges. and the couple you showed is exactly how the S equations are derived when solving welds as lines!
How about the welded connection capacity of metal ring welded on a bottom of a metal cylinder? Can you please give me an example calculation? Thank you.
Can you also do portal method example 3stories with may be 4 bays. Also, can you please share the tip and trick of how to understand and reference all the code like AISC, ACI, IBC, ASCE, ETC. I been having a hard time understanding what they are trying to say in the codes its always referring to one after another. Thank you so much for sharing your knowledge.
ua-cam.com/video/vFDMaHQ4kW8/v-deo.html 💐
I am an agricultural engineer not a civil engineer so forgive my ignorance but why are you only allowed to consider shear through the web and not the flanges? Is this in a structural code somewhere?
Hi Jesse - its not a "code" specification but how internal stresses within the beam act. There is a fantastic video that talks through the concept beautifully. I will say that it IS possible to transfer shear through the flanges but it is very difficult and provides a fraction of the capacity. check out the link for the video
ua-cam.com/video/f08Y39UiC-o/v-deo.html
Hey Wonderful Job . I want to ask that the flange weld of 1inch will be also helpful to the transfer of shear . so, the length of weld in shear direction will be 6+1+1 = 8 inch . IS it Right? Can you let me know?
you should avoid transferring shear demand through welds on flanges in this condition. cheers
Quick question, at the very end, when comparing the strength per inch of weld to the stresses you calculated (shear and moment).
Are you supposed to add the calculated stresses together (shear + moment) and compare that to phi Rn, or are you supposed to compare the shear stress value to phi Rn and moment stress value to phi Rn separately?
you need to sum the forces by squaring each stress and then adding them and taking the square root to get a resultant total stress. then you compare that single stress to the capacity phi Rn
@@Kestava_Engineering ahh okay, so take the resultant of the stresses. Thank you so much for your quick reply!
why not take into account the inside of flanges? typically that side is welded too
if you needed the addition weld for loading then you could! but dont add more weld if you dont have too, it gets expensive
Why the shear can only be transfer trouh the web?? Thanks, great content
path of least resistance. its very difficult to transfer shear stress through the webs of a WF
and the web in this case is the stiffest element
Why not using the tables for welded connections of eccentrically loaded beams, where you incorporate values of C and C1
thats a great method as well! I highly recommend using those tables
Good stuff. A quick question: need to check (phi)Rn against fb and fv combined?
i did not check for combined forces in this example because I took a conservative approach and designated the weld on the web to transfer shear stresses and the flanges to transfer bending stresses independently. if we calculated the Sx for the geometry of an I shape weld then we would definitely need to check combined forces! I should do another vid with a welding example. Great comment Matthew!
Can you do a video on PJP welds?
you sonofabitch im in! great suggestion!
Does this approach apply for sheet metal weld connections?
hmmm im not sure. I would say it does from a loading standpoint, but capacities of welds I believe is different for sheet metal and thinner metal bases.
@@Kestava_Engineering Okay got it thank you!
Can make a weld design for HSS round section subject to torsion moment? Please, and the same for shear and moment, please
oooooooo I like the sounds of that example! consider it on the list!
How I can get these handbooks
search design of welded structures and its a big blue book! its about 20$
Someone cooking bacon
bulking season