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Rule Of Thumb For Fillet Weld Size

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Rule Of Thumb For Fillet Weld Size

Rule Of Thumb For Fillet Weld Size

Veer007

(Civil/Environmental)

(OP)

13 Aug 20 10:41
This may sound silly,
If forces are unknown, is this a good practice to determine fillet weld size by the below table? Also, fillet leg and fillet size are the same?





Thanks in advance!!

Hey guysThis may sound silly,If forces are unknown, is this a good practice to determine fillet weld size by the below table? Also, fillet leg and fillet size are the same?Thanks in advance!!

RE: Rule Of Thumb For Fillet Weld Size

engineering_patrol

(Structural)

13 Aug 20 10:46

Regarding fillet width, you can estimate its size as 70% of the steel plate thickness.

RE: Rule Of Thumb For Fillet Weld Size

desertfox

(Mechanical)

13 Aug 20 11:00
My rule of thumb for fillet welds is the leg length of a fillet weld should never exceed the thickness of the smallest section being welded.

Hi Veer007My rule of thumb for fillet welds is the leg length of a fillet weld should never exceed the thickness of the smallest section being welded.

&#;Do not worry about your problems with mathematics, I assure you mine are far greater.&#; Albert Einstein

RE: Rule Of Thumb For Fillet Weld Size

phamENG

(Structural)

13 Aug 20 13:02

The "if forces are unknown" bothers me. Why are you designing a connection for which you don't know the forces? Seems like a risky proposition...

RE: Rule Of Thumb For Fillet Weld Size

dauwerda

(Structural)

13 Aug 20 13:34

I agree with phamENG, if forces are unknown it would not be good practice to use a "rule of thumb" weld. You may be able to use a weld that develops the full strength of the connected part, but this may result in excessively large welds which can introduce other issues.

RE: Rule Of Thumb For Fillet Weld Size

desertfox

(Mechanical)

13 Aug 20 13:42

Well you can&#;t have a fillet weld leg length that exceeds the plate thickness in practice, so if you choose a leg length that is the same as the minimum plate thickness, then that&#;s the strongest weld you can have unless you change the weld type to say a butt weld.

&#;Do not worry about your problems with mathematics, I assure you mine are far greater.&#; Albert Einstein

RE: Rule Of Thumb For Fillet Weld Size

dauwerda

(Structural)

13 Aug 20 13:46

desertfox, that is not true. The only time a fillet weld leg is limited by thickness is when it is welded on the edge of the plate. A T joint, for example does not have this limitation. See this thread for more information on that: https://www.eng-tips.com/viewthread.cfm?qid=

RE: Rule Of Thumb For Fillet Weld Size

phamENG

(Structural)

13 Aug 20 13:56

dauwerda - I think desertfox is getting at the development of connected part strength strategy. Once the leg gets larger than the thickness of the thinner part in a T-joint, you start getting into base material strength controlling the connection. It depends on strength of material, strength of filler, and the actual loads applied, but for a rule of thumb it's a decent practical approach.

I still go back to the not knowing the forces. In a building structure, you should always know the design load on your welds if it needs to be specified. A seal weld on a cap plate is one thing, but if you need to define a fillet weld you should know what loads to expect.

RE: Rule Of Thumb For Fillet Weld Size

desertfox

(Mechanical)

13 Aug 20 21:07
A quote from the site I use:-

The maximum size of fillet weld is generally that of the thickness of the thinner of the two items being joined but very large fillet welds may cause unacceptable distortion and/or extremely high residual stresses. In addition, above a certain size it may be more economical to make a T-butt, rather than a fillet weld.

https://www.twi-global.com/technical-knowledge/job...

see the link above

A quote from the site I use:-The maximum size of fillet weld is generally that of the thickness of the thinner of the two items being joined but very large fillet welds may cause unacceptable distortion and/or extremely high residual stresses. In addition, above a certain size it may be more economical to make a T-butt, rather than a fillet weld.see the link above

&#;Do not worry about your problems with mathematics, I assure you mine are far greater.&#; Albert Einstein

RE: Rule Of Thumb For Fillet Weld Size

dauwerda

(Structural)

13 Aug 20 21:40

If you don't know the loads that a weld needs to be designed for, the only safe rule of thumb is going to be to provide a weld that will develop the strength of the base metal. For a fillet weld this will result in a leg size that is larger than the thickness of the base metal if it is a one-sided weld (such as is the case with a tube welded to base plate). As noted above, excessively large fillet welds can lead to other issues. Hence the reason I say there is no good rule of thumb for fillet weld size if the loads are unknown.

RE: Rule Of Thumb For Fillet Weld Size

desertfox

(Mechanical)

13 Aug 20 23:07
Further to develop the full strength of of the base material using a fillet weld the leg size of the weld only needs to be 3/4 of the material thickness and this applies to TEE joints.
see link below:-

https://www.linkedin.com/pulse/rule-thumb-fillet-w...

dauwerda if the table shown in the op's original post shows all the fillet weld sizes to be less than the thickness of the material being welded why are you assuming he has a TEE joint?Further to develop the full strength of of the base material using a fillet weld the leg size of the weld only needs to be 3/4 of the material thickness and this applies to TEE joints.see link below:-

&#;Do not worry about your problems with mathematics, I assure you mine are far greater.&#; Albert Einstein

RE: Rule Of Thumb For Fillet Weld Size

Veer007

(Civil/Environmental)

(OP)

14 Aug 20 12:59

Quote (phamENG)

so the only considerable thing is weld size should not be lesser than 1/4Xt, Right?

so the only considerable thing is weld size should not be lesser than 1/4Xt, Right?

Thanks in advance!!

RE: Rule Of Thumb For Fillet Weld Size

desertfox

(Mechanical)

14 Aug 20 13:40

Well yes you are right but it depends on what you are doing, to develop full strength in the welds compatible with the plate you need 3/4 x plate thickness on both sides of the joint, if you are just wanting rigidity then weld leg length is 1/4 x plate thickness, but if you don&#;t know what the loads on the joint are then surely the best you can do is develop full plate strength in the welds

Hi veerWell yes you are right but it depends on what you are doing, to develop full strength in the welds compatible with the plate you need 3/4 x plate thickness on both sides of the joint, if you are just wanting rigidity then weld leg length is 1/4 x plate thickness, but if you don&#;t know what the loads on the joint are then surely the best you can do is develop full plate strength in the welds

&#;Do not worry about your problems with mathematics, I assure you mine are far greater.&#; Albert Einstein

RE: Rule Of Thumb For Fillet Weld Size

dauwerda

(Structural)

14 Aug 20 13:41

Quote (desertfox)

dauwerda if the table shown in the op's original post shows all the fillet weld sizes to be less than the thickness of the material being welded why are you assuming he has a TEE joint?

The OP didn't tell anything other than that it is a fillet weld, so my assumption is that it can be any type of joint that can be welded with a fillet weld.

Quote (desertfox)

Further to develop the full strength of of the base material using a fillet weld the leg size of the weld only needs to be 3/4 of the material thickness and this applies to TEE joints.
see link below:-

Did you see all the assumptions listed in your link that need to be true for this to be true, mainly the requirement that the fillet weld be on both sides of the plate. A fillet weld with a leg size 3/4 of the material thickness does not develop the strength of the material - two fillet welds with 3/4 of the material thickness do.

The OP did not give any indication of joint type, just asked if that table (which also doesn't give any more detail) is a good table to use as a rule of thumb for fillet weld sizes when forces are unknown. I have responded with reasons why it is not a good idea to use it as a rule of thumb for certain types of fillet welds. It certainly may work for some situations, but it is not a catch all (isn't that what a rule of thumb is supposed to be? or if not, at least include the situations it is and isn't applicable to) and it gets even more concerning if someone is trying to apply it to joints where they have no idea what the loads they need to resist are. Perhaps that table has footnotes to make sure it is not misapplied, but the information given in the OP does not include anything about where it should or shouldn't be applied or that it is providing information for two-sided fillet welds. I believe it is prudent to point out where it doesn't work as none of this was included in the OP.

The OP didn't tell anything other than that it is a fillet weld, so my assumption is that it can be any type of joint that can be welded with a fillet weld.Did you see all the assumptions listed in your link that need to be true for this to be true, mainly the requirement that the fillet weld be on both sides of the plate. A fillet weld with a leg size 3/4 of the material thickness does not develop the strength of the material -fillet welds with 3/4 of the material thickness do.The OP did not give any indication of joint type, just asked if that table (which also doesn't give any more detail) is a good table to use as a rule of thumb for fillet weld sizes when forces are unknown. I have responded with reasons why it is not a good idea to use it as a rule of thumb for certain types of fillet welds. It certainly may work for some situations, but it is not a catch all (isn't that what a rule of thumb is supposed to be? or if not, at least include the situations it is and isn't applicable to) and it gets even more concerning if someone is trying to apply it to joints where they have no idea what the loads they need to resist are. Perhaps that table has footnotes to make sure it is not misapplied, but the information given in the OP does not include anything about where it should or shouldn't be applied or that it is providing information for two-sided fillet welds. I believe it is prudent to point out where it doesn't work as none of this was included in the OP.

RE: Rule Of Thumb For Fillet Weld Size

phamENG

(Structural)

14 Aug 20 14:10

For what it's worth, I agree completely with dauwerda. In my last post, I was thinking of a two sided T - sorry I wasn't more clear.

If I need to rely on a weld for any kind of strength, 1/4t is too small. Take a look at Table J2.4 in AISC. Minimum fillet weld sizes are all larger than 1/4t. And, of course, that's the bare minimum. You really need to know what your forces are to determine your weld size. Just going for full capacity of the connected parts will, in most cases, result in a grossly over designed, inefficient, and expensive connection. A consulting or design engineer may get away with that occasionally or on small jobs, but you work for a fabricator where cost of each connection matters on every job. Do that very often and they'll probably show you the door.

RE: Rule Of Thumb For Fillet Weld Size

desertfox

(Mechanical)

14 Aug 20 14:27

You clearly stated in your post that I was wrong and in your next post that to develop full plate strength the weld leg length would need to be larger than the plate thickness. Which is also incorrect.

I didn&#;t make the assumption about double sided welds but looked at the table provided which clearly shows fillet weld leg lengths less than the material thickness which was the point I was making.
I agree that without knowing the forces on the joint the best anyone can do is develop the weld strength to match the plate strength but he doesn&#;t need a leg length to exceed the plate thickness

DauwerdsYou clearly stated in your post that I was wrong and in your next post that to develop full plate strength the weld leg length would need to be larger than the plate thickness. Which is also incorrect.I didn&#;t make the assumption about double sided welds but looked at the table provided which clearly shows fillet weld leg lengths less than the material thickness which was the point I was making.I agree that without knowing the forces on the joint the best anyone can do is develop the weld strength to match the plate strength but he doesn&#;t need a leg length to exceed the plate thickness

&#;Do not worry about your problems with mathematics, I assure you mine are far greater.&#; Albert Einstein

RE: Rule Of Thumb For Fillet Weld Size

dauwerda

(Structural)

14 Aug 20 15:10

Quote (desertfox)

Dauwerds

You clearly stated in your post that I was wrong

I believe you are referring to this post:

Quote (dauwerda)

desertfox, that is not true. The only time a fillet weld leg is limited by thickness is when it is welded on the edge of the plate.

which was in response to your post:

Quote (desertfox)

Well you can&#;t have a fillet weld leg length that exceeds the plate thickness in practice, so if you choose a leg length that is the same as the minimum plate thickness, then that&#;s the strongest weld you can have unless you change the weld type to say a butt weld.

Which I will again state, is incorrect.

Quote (desertfox)

in your next post that to develop full plate strength the weld leg length would need to be larger than the plate thickness. Which is also incorrect.

I agree that this statement is not true for a two-sided fillet weld, but it certainly is true for a one sided fillet weld which is why I specifically stated that. Again, the OP didn't give any information as to what he/she was planning on applying this to.

Quote (desertfox)

I didn&#;t make the assumption about double sided welds but looked at the table provided which clearly shows fillet weld leg lengths less than the material thickness which was the point I was making.

That table does not state anywhere that it is for double sided fillet welds. You can look at it and infer that that is what it is for because of your experience. I don't believe it is a good thing to assume that the OP (or anyone else that finds this thread in a google search looking for a rule of thumb on fillet welds) can also recognize that without pointing it out. I can very easily imagine someone seeing the information provided and misapplying it.

I believe you are referring to this post:which was in response to your post:Which I will again state, is incorrect.I agree that this statement is not true for a two-sided fillet weld, but it certainly is true for a one sided fillet weld which is why I specifically stated that. Again, the OP didn't give any information as to what he/she was planning on applying this to.That table does not state anywhere that it is for double sided fillet welds. You can look at it and infer that that is what it is for because of your experience. I don't believe it is a good thing to assume that the OP (or anyone else that finds this thread in a google search looking for a rule of thumb on fillet welds) can also recognize that without pointing it out. I can very easily imagine someone seeing the information provided and misapplying it.

RE: Rule Of Thumb For Fillet Weld Size

cliff234

(Structural)

14 Aug 20 15:35

If the forces are unknown, you cannot safely determine the economical weld size.

In general, a fillet weld made with E70 electrodes will provide a service level load capacity of 0.928 kips per inch per 1/16" of weld size. (example: A 1/4" fillet weld would be good for 3.7 kips per inch) There are many other issues related to weld size/strength that I did not go into, but this is a start. I would suggest talking to a structural engineer to get a comprehensive answer to your questions. Ask them to review your proposed detail. Most structural failures are connection failures. Don't try to design connections unless you know what you are doing.

By the way... That's a frightening table you posted. "Rules of Thumb Fillet Weld Sizes"?! That's like a list "Rules of thumb for disarming land mines". The fact that this table appears to have been published in a book is especially disturbing.

RE: Rule Of Thumb For Fillet Weld Size

desertfox

(Mechanical)

14 Aug 20 15:40

If you have two plate edges at right angles and can only weld on one side then the leg length Of the weld cannot exceed the thickness of Of the thinnest section.In fact in the above situation the best you can do As make the leg length the thickness of the plate to be welded as I previously stated.
The people that frequent the site are supposedly professional engineers and Therefore should have some knowledge of engineering so I don&#;t make assumptions about what they know and don&#;t know, bear in mind the OP has been a member for four years. If the OP was misapplying it he wouldn&#;t be asking would he.

Explain to me how with two plate edges say 10mm thick at ninety degrees to each other you can produce a leg length of weld larger than 10mm.

DauwerdsIf you have two plate edges at right angles and can only weld on one side then the leg length Of the weld cannot exceed the thickness of Of the thinnest section.In fact in the above situation the best you can do As make the leg length the thickness of the plate to be welded as I previously stated.The people that frequent the site are supposedly professional engineers and Therefore should have some knowledge of engineering so I don&#;t make assumptions about what they know and don&#;t know, bear in mind the OP has been a member for four years. If the OP was misapplying it he wouldn&#;t be asking would he.Explain to me how with two plate edges say 10mm thick at ninety degrees to each other you can produce a leg length of weld larger than 10mm.

Additional resources:
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How to Choose Plasma Cutter Temperature

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&#;Do not worry about your problems with mathematics, I assure you mine are far greater.&#; Albert Einstein

RE: Rule Of Thumb For Fillet Weld Size

jayrod12

(Structural)

14 Aug 20 16:01

I think what dauwerda is trying to say is that, for example, if you had two 1/4" thick plates at 90 degrees to each other, there's nothing stopping you from laying a 3/8" thick fillet weld connecting them. But that's uneconomical and wasteful in most instances since the weld strength will be far in excess of the base metal thickness. If you are trying to weld too close to the end of the plate, or to the edge of the plate, then you are obviously bound by the plate thickness (or the distance to the edge of your plate) when determining the weld leg length.

RE: Rule Of Thumb For Fillet Weld Size

r13

(Civil/Environmental)

14 Aug 20 17:22

I think the rule of thumb can be used for a large project, with many secondary/miscellaneous connections that do not have/carry structural significance, to facilitate the project manpower utilization, and construction flow. Similar to the note "all bolts shall be A325 5/8" diameter....u.n.o."

RE: Rule Of Thumb For Fillet Weld Size

phamENG

(Structural)

14 Aug 20 19:15

retired - I think I see what you're getting at, and I agree with the concept. But I would say that's not a rule of thumb. By all means, take all (or some reasonable grouping) of similar connections and provide one design based on the worst case loads. But design it for the load and not based on a rule of thumb.

RE: Rule Of Thumb For Fillet Weld Size

r13

(Civil/Environmental)

14 Aug 20 19:46

I think you are too focus on the name "rule of thumb" of the table. Rather it is a guide to minimize the unnecessary guessing when detail are not present, but the word in spec for such situation - "see table". The table does not rule out the engineer's duty to provide detailed design, and at least to filter out the suitability to refer to such table. I think that's the intent of the author who made the table - a design aid.

RE: Rule Of Thumb For Fillet Weld Size

mfrad

(Structural)

15 Aug 20 19:41
Your table came from Omer Blodgett's, "Design of Weldments" which is a good start.
Everyone's comments are solid information. I added two tables from AISC as my starting point and I hope it will help you zeroing in on the weld strength or plate size. I would memorized Table 3.2 to know the minimum weld size that I need for the steel plate being used. This is a mimimum bound on the size. The upper table gives you the minimum plate thickness for Grade 36 and 50, so that the weld size D strength for double sided welds can be developed. For a single weld line use 3.09 vs 6.18 so the plate thickness required for that weld will be half. (I added the formula for plate thickness to calculate for other grades of steel, this table is based upon E70 electrodes.)

Must check shear and tension strength of the plate too, then you will have a range of the connection capacity for design or analysis.

• https://files.engineering.com/getfile.aspx?folder=3ac-af80-401b-965c-e

Veer007,Your table came from Omer Blodgett's, "Design of Weldments" which is a good start.Everyone's comments are solid information. I added two tables from AISC as my starting point and I hope it will help you zeroing in on the weld strength or plate size. I would memorized Table 3.2 to know the minimum weld size that I need for the steel plate being used. This is a mimimum bound on the size. The upper table gives you the minimum plate thickness for Grade 36 and 50, so that the weld size D strength for double sided welds can be developed. For a single weld line use 3.09 vs 6.18 so the plate thickness required for that weld will be half. (I added the formula for plate thickness to calculate for other grades of steel, this table is based upon E70 electrodes.)Must check shear and tension strength of the plate too, then you will have a range of the connection capacity for design or analysis.

RE: Rule Of Thumb For Fillet Weld Size

IFRs

(Petroleum)

15 Aug 20 21:56
https://www.eng-tips.com/viewthread.cfm?qid=

This might be considered a double post, see thread 507-

RE: Rule Of Thumb For Fillet Weld Size

phamENG

(Structural)

16 Aug 20 19:34

IFRs - I disagree. There's a good month between the posts, and in the one you referenced he's asking if there is a calculation to better determine MINIMUM weld size. Here, he's looking for a rule of thumb to use when designing - not what the minimum size is (though some of the discussion has gone back to that).

RE: Rule Of Thumb For Fillet Weld Size

Veer007

(Civil/Environmental)

(OP)

17 Aug 20 08:47

Where would you recommend this rule of thumb table ? can you advise me on the conditions?

Also, is there no conditions that weld size rely on plate thick? nowhere?

Guys if this is T-joint, if 3/16" weld is enough for given force when I have 3/4" thick plate as thinner part, I should not use, right? So I have to go with 5/16" min weld as per J2.4,Where would you recommend this rule of thumb table ? can you advise me on the conditions?Also, is there no conditions that weld size rely on plate thick? nowhere?

Thanks in advance!!

RE: Rule Of Thumb For Fillet Weld Size

desertfox

(Mechanical)

17 Aug 20 09:24

Can you give details of the joint you are trying to weld, if this is a tee joint can it be welded on both sides? Also if the thinner part is 3/4&#; thickness then the table you posted suggests a 9/16&#; weld to develop full strength.
To get the best answer we need to know what exactly you are welding and it&#;s function otherwise we are making assumptions and second guessing and you won&#;t get a correct answer.

Hi veer007Can you give details of the joint you are trying to weld, if this is a tee joint can it be welded on both sides? Also if the thinner part is 3/4&#; thickness then the table you posted suggests a 9/16&#; weld to develop full strength.To get the best answer we need to know what exactly you are welding and it&#;s function otherwise we are making assumptions and second guessing and you won&#;t get a correct answer.

&#;Do not worry about your problems with mathematics, I assure you mine are far greater.&#; Albert Einstein

RE: Rule Of Thumb For Fillet Weld Size

Veer007

(Civil/Environmental)

(OP)

17 Aug 20 10:17

below is the connection that will show you details, connection plates are 3/4" thick mentioned by EOR.

I can't have UDL for tube sections from CISC.below is the connection that will show you details, connection plates are 3/4" thick mentioned by EOR.

Thanks in advance!!

RE: Rule Of Thumb For Fillet Weld Size

desertfox

(Mechanical)

17 Aug 20 10:22

Have you another view of the section? Is it a &#;c&#; section you are welding, I can&#;t tell from one view what exactly you are trying to do. Are you welding the blue section onto the yellow bracket?

Hi veer007Have you another view of the section? Is it a &#;c&#; section you are welding, I can&#;t tell from one view what exactly you are trying to do. Are you welding the blue section onto the yellow bracket?

&#;Do not worry about your problems with mathematics, I assure you mine are far greater.&#; Albert Einstein

RE: Rule Of Thumb For Fillet Weld Size

Veer007

(Civil/Environmental)

(OP)

17 Aug 20 10:27

Both yellow are connection plates, the blue one is Girt HSS254x254x12.7 and Pink is w-column

Thanks in advance!!

RE: Rule Of Thumb For Fillet Weld Size

mfrad

(Structural)

17 Aug 20 10:57

Veer007
Blodget's table is not based on weld strength, nor plate strength. Fillet sizes are proportional to either E60, E70 or E80 welding rods. His book covers both building and machine design. In buildings the bottom half of the table fillet welds are not economical, suggest dropping fillet weld greater than 3/8 for buildings. The right column (33%) with asterisks is AISC the thinner plate weld size. PhamEng has clearly stated in his earlier response thread that thickness also relates to preheat requirements.

Your last sentence indicates 5/16ths weld. You can use intermittent spacing as one alternate. Therefore Blogetts table is not that useful in itself.

RE: Rule Of Thumb For Fillet Weld Size

desertfox

(Mechanical)

17 Aug 20 11:44

So the yellow plates sit on either side of the HSS section?

Veer007So the yellow plates sit on either side of the HSS section?

&#;Do not worry about your problems with mathematics, I assure you mine are far greater.&#; Albert Einstein

RE: Rule Of Thumb For Fillet Weld Size

Veer007

(Civil/Environmental)

(OP)

17 Aug 20 12:21

No, one is a gusset plate and another one is the connection plate which slots the HSS tube.

Thanks in advance!!

RE: Rule Of Thumb For Fillet Weld Size

desertfox

(Mechanical)

17 Aug 20 13:05

Hi veer007

So the a plate is welded central in the HSS tube And then using bolts that plate is fastened to the gusset plate is that right ? Also how is the HSS section loaded when in position?

&#;Do not worry about your problems with mathematics, I assure you mine are far greater.&#; Albert Einstein

RE: Rule Of Thumb For Fillet Weld Size

phamENG

(Structural)

17 Aug 20 13:06

Quote (Veer007)

I can't have UDL for tube sections from CISC.

Do you mean that the EOR put said to design all connections for 1/2 UDL values but the code you're using doesn't have UDL values for HSS? If that's the case, stop guessing. Stop trying to use rules of thumb. Stop doing anything but sending an RFI to the EOR and requesting a reaction because they failed to give you one. You're designing connections on behalf of the fabricator - the EOR is responsible for analysis of the structure. Get the data he/she is required to give you and don't roll the dice. It's not worth it for you, your employer, or the people who may one day walk into that building.

Veer - let's back up for a second. You say the following:Do you mean that the EOR put said to design all connections for 1/2 UDL values but the code you're using doesn't have UDL values for HSS? If that's the case, stop guessing. Stop trying to use rules of thumb. Stop doing anything but sending an RFI to the EOR and requesting a reaction because they failed to give you one. You're designing connections on behalf of the fabricator - the EOR is responsible for analysis of the structure. Get the data he/she is required to give you and don't roll the dice. It's not worth it for you, your employer, or the people who may one day walk into that building.

RE: Rule Of Thumb For Fillet Weld Size

Veer007

(Civil/Environmental)

(OP)

17 Aug 20 13:57

Quote (phamENG)

I greatly appreciate all your point. You are my one of inspiration.

I never going to do anything without confirmation or getting approval from EOR.

What was my concern is, Is this a good practice to follow thumb rule when there is a case, That we are not sure about load but we know the thickness of either bare/connected plate thickness.

I know a real engineer never going to use this thumb rule/J2.4 at anywhere without knowing force, but I want to say one thing, in detailing industry EOR never going to address each and every location, we also have to take some decision without EOR interference. In deep, EOR never gave us proper forces at all locations instead of saying connect for 50% UDL or full capacity of a member.

If we have to connect steel for its full capacity we end with larger weld, Meantime contractor pushes the fabricator for expediting deliver the steel to site.

We generally ask torsional force, axial force, moment forces, and lateral force... But if come to the point, we have to connect column with Beam/HSS for shear force using handbooks.

Also if connections seem too scary, we have to raise RFI states is this fine or not? Then they are changing original contract dwg.

So we often look for thumb rule that ends with better performance as well as safety too, we connection designer never going to do if something is not proper connection even if fabricator prefers, we will inform him/her that we should use this for better performance.

All these processes leads to more time than expected.

Thanks in advance!!

I greatly appreciate all your point. You are my one of inspiration.I never going to do anything without confirmation or getting approval from EOR.What was my concern is, Is this a good practice to follow thumb rule when there is a case, That we are not sure about load but we know the thickness of either bare/connected plate thickness.I know a real engineer never going to use this thumb rule/J2.4 at anywhere without knowing force, but I want to say one thing, in detailing industry EOR never going to address each and every location, we also have to take some decision without EOR interference. In deep, EOR never gave us proper forces at all locations instead of saying connect for 50% UDL or full capacity of a member.If we have to connect steel for its full capacity we end with larger weld, Meantime contractor pushes the fabricator for expediting deliver the steel to site.We generally ask torsional force, axial force, moment forces, and lateral force... But if come to the point, we have to connect column with Beam/HSS for shear force using handbooks.Also if connections seem too scary, we have to raise RFI states is this fine or not? Then they are changing original contract dwg.So we often look for thumb rule that ends with better performance as well as safety too, we connection designer never going to do if something is not proper connection even if fabricator prefers, we will inform him/her that we should use this for better performance.All these processes leads to more time than expected.Thanks in advance!!

RE: Rule Of Thumb For Fillet Weld Size

dauwerda

(Structural)

17 Aug 20 14:03

This is a bit off topic, but I would prefer to see that connection made with a WT or an end plate welded to the HSS so that the shear is directly transferred to the web of the HSS rather than through bending of the flanges.

RE: Rule Of Thumb For Fillet Weld Size

phamENG

(Structural)

17 Aug 20 14:35

Veer - I would say the only time to use a rule of thumb would be to put a cost estimate together. Preliminary design phase, rules of thumb are a good tool to get in the right ballpark and set everyone's expectations. Once you get past that, stop using them. If you find yourself in a situation where the EOR is failing to do his/her job, and you have no choice but to design for the "full strength of the member" (which is a pretty loaded requirement and can have some seriously complicating repercussions if you take it far enough), then don't use a rule of thumb for it. Figure out the capacity of the member and use that number to do actual calculations.

RE: Rule Of Thumb For Fillet Weld Size

Veer007

(Civil/Environmental)

(OP)

18 Aug 20 08:42

Quote (dauwerda)

Apologies, if this is irrelevant I just want to say the fact.

Apologies, if this is irrelevant I just want to say the fact.

Thanks in advance!!

RE: Rule Of Thumb For Fillet Weld Size

Veer007

(Civil/Environmental)

(OP)

18 Aug 20 08:59

Quote (desertfox)

So the a plate is welded central in the HSS tube And then using bolts that plate is fastened to the gusset plate is that right ? Also how is the HSS section loaded when in position?

Right and This HSS going to support a CMU wall over the opening.

Right and This HSS going to support a CMU wall over the opening.

Thanks in advance!!

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