Old steel beam classification?

[Redacted]

Hi there,

I am trying to determine the section properties and yield strength of an old beam shown in some 1962 drawings.

It was a UK company that did the drawings, which is leading me to believe that it is actually a UK universal beam.

It states 10"x5-3/4" UB x 21# Cross beam (H.Y.S)

The closest UK beam I could find that has similar dimensions is the 254x146x31 universal beam.

I am guessing that HYS stands for high yield steel? If so what kind of yield strength would that have been in the 1960s for a bridge application?

See attached image.

 

[Retrograde]

There is some relevant information in the "Historical Structural Steelwork Handbook".

You can probably find a copy via Google.

 

[dhengr]

That’s probably a W10x21, 9.9" deep and a 5.75" flg. width, from the AISC Manual, 5th & 6th Eds. There were several different HSLA steels by the time of the 6th Ed.

 

[Ingenuity]

I agree with dhengr ==> W10x21: From AISC Manual 5th Edition, 30th Printing:

Look at AISC DG#15 for mechanical properties by year: Part extract:

 

[Redacted]

Thanks all for the responses so far.

I am surprised that the yield strength is so low for the A7-61T and A36-62T. I would've expected H.Y.S. steel to be at least 300 MPa.

 

[dik]

Just confirm the physical dimensions are the same as a W10x21 aka
10WF21, 10B21 or B10x21.

Dik

 

[Redacted]

Hi Dik,

Yea I can confirm that the physical dimensions are :

10x5.75x21

depth = 9.9 “ = 251.46mm

breadth = 5.75” = 146 mm

web thickness = 0.24” = 6.1mm

flange thickness = 0.34” = 8.6mm

area = 6.2 inch2 = 4000 mm2

second moment = 106.3 inch4 = 44120531.2 mm4

section mod = 21.5 inch3= 352321.9 mm3

 

[dik]

Data is similar for a W10x21...

Dik

 

[Lomarandil]

Rstars, bridge steel has often lagged behind the yield properties used for building steel in a given time period.

From the Manual of Bridge Evaluation (which governs evaluation of existing structures), you'd want to assume A7 (33ksi) steel given a lack of any other information.

In the 30s and 40s, some designers used "Silicon Steel" or other alloys which had higher yield strengths -- but these were out of favor by the 60s due to lack of weldability and ductility among other concerns.

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The name is a long story -- just call me Lo.