Dimension "k1" of Historic Steel Sections: 27WF102, 33WF130, 33WF141 (year of fabrication 1

[AK4S]

I am trying to find the value k1 (Detailing distance from center of web to flange toe of fillet, in.) for the Historic Steel Sections: 27WF102, 33WF130, 33WF141 (year of fabrication 1959).

I need the dimension to estimate the width of fillet weld at the Web-Flange interface in order to estimate the thickness of a filler plate (required to bypass the weld) for the below connection:

Also, is there a minimum dimension I would need to consider (beyond the weld) to estimate the thickness of the filler plate.
Per below extract from the State Bridge Manual for a connection plate, a dimension of 2*tw is recommended.
Considering this would require a considerably thick filler plate. For example for 33WF141, 2*tw = 2 x 0.605" = 1.21".
Any suggestions?

 

[Phil1934]

http://www.slideruleera.net/Carnegie Pocket Companion-1934.pdf

 

[AK4S]

@Phil1934: Thanks for sharing the link. Since these are CB beams, I was only able to locate the dimension corresponding to 33WF141(it is a Bethlehem Steel section I think).For the matching section shown in below extract of page #10 of the PDF, the width of the fillet weld is = 1.75"-0.9375" = 0.8125"
Am I interpreting this correctly? Since the detailing flange thickness (0.9375") is less than design flange thickness (0.96").

 

[Phil1934]

That's how I read it, but I'm a geotech . There are more steel charts on slideruleera

 

[kipfoot]

The Bethlehem tables don't give the number directly, but I think you'll get the same answer.

 

[AK4S]

@kipfoot: Thanks for sharing the scans. However, I am looking for a more definitive confirmation of this dimension, since my filler plate thickness will be dependent on it.

 

[r13]

AK4S,

This link you to ASCE library for historical steel producers, and manuals. You will need to spend sometime to dig into it. Also note, the radius of the fillet is only list for information, deviation might occur. So be generous when consider the cut dimension in your plate.

Link

 

[SlideRuleEra]

I am looking for a more definitive confirmation of this dimension...

It does not get any better than the information kipfoot posted... catalog cuts from the beam's producer that date to the approximate age of the beams. Every bit of information you have requested, for all three beam sizes, can be extracted from the catalog pages. It's just not presented in the (modern) way you are expecting. Revisit the catalog and do the math, you'll learn more than just being given the answers.

In your other thread, bridgebuster told you that "...steel repairs are combination of art and science...". You have performed plenty of "science", it's past time apply "art", so that the repair "parts" fit the deteriorated existing beams without finding out, in the field, at the last minute that a (theoretically) precisely sized repair "part" too big... and its back to the drawing board while the contractor (with the clock running) waits for a revision.

BTW, while looking again at the catalog, note the that the inner face of the flange (for all three size beams) is not parallel with the outer face. The inner face has a 5% slope, the angles in the proposed detail will not (theoretically) fit correctly.

http://www.SlideRuleEra.net

 

[r13]

Maybe consider to provide a note on the dimensions - "filed to verify", or "field fit required". I think it is not unusual to request a shop drawing submittal, so you can adjust/change the contract drawing accordingly, or catch major deviations/discrepancies.

 

[AK4S]

@SRE:You are correct. I was looking for the k1 values similar to what we see in the current steel book.I could not find them in the old steel books I had access to and thought there could be other documents with published values.

The values I estimated were all over the place (See snapshot below) and so was looking for a confirmation.

I understand these weld dimensions I am estimating are "theoretical" and actual values could vary, so I cannot size my filler plate to exact weld dimensions.
The extract of the State Bridge Manual I posted for a connecting plate, requires a dimension of 2*tw for the bevel which is 1.21". Using a 1.25" thick filler plate in my case seemed excessive/not efficient to just bypass the fillet.

Hence, I was trying to get a better estimate of the fillet size and also know if there is any way to estimate how much allowance I should consider for variations in order to select the filler plate width. I was thinking of using 1" thick for all cases.

 

[AK4S]

@SRE: Thanks for pointing out regarding the slope in the inner face of the flange.
On the other thread, I was thinking of modifying the detail to use a filler plate on the inside (to by pass the weld), web-plate on the outside (tw/2 thick and finished to bear against the bottom flange) and then the angle to transfer the horizontal component of shear force to the bottom flange.

Considering the above configuration, I was assuming that the slight slope could be adjusted in field by packing with shims below the angle.

 

[SlideRuleEra]

...requires a dimension of 2*tw for the bevel which is 1.21". Using a 1.25" thick filler plate in my case seemed excessive/not efficient to just bypass the fillet. I was thinking of using 1" thick for all cases.

Do you have several decades of experience with large, heavily loaded beams, like bridgebuster?
If not, suggest not arbitrarily "tossing" the results of the calcs out the window based on intuition and going with what... a guess with no hard backup?

Repairs are always a "hands-on" project, advance field verification of dimensions, distortion, deterioration, etc. are essential. Often will take more than one site visit to get enough correct info to design a constructable repair that works when it counts...the first time. This is not the type project where only "thinking it through" is enough.

For example, will there be access to make specified welds, or is "something" not considered for design in the way?

http://www.SlideRuleEra.net

 

[AK4S]

@SRE: I believe my response was not clear as I have no intention to toss the results of any calculation or standards. The extract of the bridge manual I posted was what I found for a connection plate (installed perpendicular to the web). It calls for the bevel in the plate to be 5*tw high by 2*tw wide. I am not sure if these requirements are really applicable to the configuration in my sketch, which is for an additional web-plate (installed parallel to the web).
I could not find any other reference, hence I had posted the question to know if "there a minimum dimension I would need to consider (beyond the weld) to estimate the thickness of the filler plate."

A brief from the discussion on the other thread:
I had referred to the FHWA design example shared by Bridgebuster, where basically we design for shear (using new tw/2 thick web plates on either side to provide sufficient material area to compensate for the thickness loss in the existing web). However, I was left with the problem of interference with the fillet weld in the existing web.
One option was to use a beveled plate for total thickness or to use a combination of filler plate (to get past to get past the fillet) and an unbeveled repair plate.

 

[SlideRuleEra]

AK4S - I overreacted to your post, sorry. From the photos in the other thread, appears much deterioration has taken place in 60 years. Saw that the bridge is being overhauled not just repaired, so assume a useful life of several more decades is expected. Even with improved modern paints and coatings there may be significant corrosion of the repair in the future. A corrosion allowance seems warranted.

Also, I always keep in mind the "strength" (a member's section modulus) is proportional to the square of the depth.
"Stiffness" (moment of inertia) is proportional the cube of the depth.
An 1 1/4" plate is 56% "stronger" and 95% "stiffer" than a 1" plate.
Perhaps that intuition is not needed for the application.

http://www.SlideRuleEra.net

 

[AK4S]

@SRE No worries! Thanks for your inputs.