old roof framing member designations 1

[whir]

I am looking at a building that has drawings dated in 1960. Some of the framing has designations for "L" joists from the 50's. There are some joist framing members that span about 16'-0" that appear to be designated "12-1056" and "8-1256" spaced at 4'-0". Does anyone know what this framing designation is or if it is referring to something else?

Thanks for the help

 

[MiketheEngineer]

Is this steel or wood?? Got any pictures??

 

[whir]

I am going there tomorrow. I am trying to get an idea of what to expect when I get there.

 

[racookpe1978]

My "AISC Search Utility for Structural Steel, V13" has several "sort-of-similar" listings under the "Historic" section.

They have them listed as both "12BL" "B12L" - for 12" Bethlehem shapes of different weights.

Also listed were "10BL" or "B10L" and "8BL" or "B8L" - the BL designation was evidently stopped from production in 1948. (A little before the year of your building, so that is consistent with somebody using an old Shapes book for the drawing.)

Didn't see any sub-designations comparable to 1056 or 1256 though.

An "L" shape is (usually) an alternate designation for an AN or angle shape in modern terms.

 

[racookpe1978]

From the "8BJ" or "BJ8" designations from that same AISC search utility, these cross-references are in the "Footnotes" or "FSTR" section. Other data is the design data for the 8BJ steel section.

Library: HISTORIC
Type: ALL (Weight)
ID = 367
Designation = 8BJ,BJ8
W = 10
A = 2.95
D = 7.9
TW = 0.17
BF = 3.94
TF = 0.204
T = 6.865
K = 0.517
BF_2TF = 9.66
H_TW = 40.4
FY3P = 39
X1 = 1860
X2 = 14532
IX = 30.8
ZX = 8.6
SX = 7.8
RX = 3.23
IY = 2
ZY = 1.6
SY = 1
RY = 0.82
J = 0.04
CW = 30
a = 41.5
WNO = 7.58
SW = 2
QF = 1.48
QW = 4
FSTR =
BJ12-10-8-X4,S43 1933,
S47 1934,
12BL-10BL-8BL-X4,S51 1938,
S53 1943,
S54 1946,
S56 1948,

 

[whir]

Thanks for the information. I will post a message tomorrow to let you know what I actually found.

 

[racookpe1978]

So, in those "alternate names" you'll see the "56" designation from 1948, and the "BJ12", "12BL" "names" that your previous engineer might have been (desperately) trying to callout as he made a drawing in the mid-60's paging through an obsolete catalog written in the mid-50's looking for shapes that hadn't been made since 1948. By a Bethlehem steel mill that hasn't existed since the mid-80's.

For a designer looking at steel under a roof that will be worked on in the early 2010's.

 

[racookpe1978]

Here is the 10BJ, BJ10 data. For what it's worth. Looks like a W12 wannabe, but the alternate names are comparable. Odd.

Library: HISTORIC
Type: ALL (Weight)
ID = 366
Designation = 10BJ,BJ10
W = 12
A = 3.39
D = 9.87
TW = 0.18
BF = 3.95
TF = 0.204
T = 8.835
K = 0.517
BF_2TF = 9.68
H_TW = 49.1
FY3P = 27
X1 = 1585
X2 = 31596
IX = 51.9
ZX = 11.8
SX = 10.5
RX = 3.92
IY = 2
ZY = 1.7
SY = 1
RY = 0.77
J = 0.05
CW = 47
a = 48.8
WNO = 9.55
SW = 2
QF = 1.86
QW = 6
FSTR =
BJ12-10-8-X4,
S43 1933,
S47 1934, 12BL-10BL-8BL-X4,S51 1938,
S53 1943,
S54 1946,
S56 1948,