Working load capacities of E70XX weld

[MNZ1]

I am reviewing the capacity of an existing building in Canada, built in 1965.
The connection welds were designed for the following working load weld capacities (screenshot below taken from the original drawings. These seem to be much lower than what an E70XX weld should be capable of, even considering SLS design.
For e.g., a 1/4 inch weld should be more like 3.7 kip/in.

Any ideas of why these working load weld capacities are lower?

 

[dik]

I dunno... never used working stress... even back in '65. For 1/4" E70...last line just the variable values...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[JAE]

For ultimate level capacity welds per AISC are 0.6 x 0.75 x 70 = 31.5 ksi
Taking that value and using a 1/4" fillet weld you get 0.25 x 0.707 x 31.5 = 5.57 kips/in.

For service level loads in the US we've typically used a 0.6 factor on an ultimate load or capacity.
That would then equate to a working stress level capacity for a 1/4" fillet at 3.34 kips/in.

It looks like the table you posted uses 0.5 instead of 0.6.
0.5 x 5.57 = 2.8 kips/in.

 

[WinelandV]

For whatever reason, that table appears to be ~ 75% of the expected ASD capacity. That is, instead of 0.93 kip/in/16th, 0.7 kip/in/16th was used.

Please note that is a "v" (as in Violin) not a "y".