help identifying an irregular OWSJ chord
help identifying an irregular OWSJ chord
(OP)
Hello,
I am trying to analyze an open web steel joist in an existing building in Ontario, Canada.
My problem is, the top and bottom chords of the joist are an irregular shape that I have never seen before. If someone can help me identify the shape, and help me find the section properties, I will be able to analyze the joist. I have attached a picture of the cross section in question.
Some browsing around past threads has led me to the macomber v-beam series of chords. I have downloaded some information on the sizes they made, and this has been a great help. I guess I'm wondering if anyone can tell me if this was the manufacturer for sure, or if other companies were also making this shape.

I am trying to analyze an open web steel joist in an existing building in Ontario, Canada.
My problem is, the top and bottom chords of the joist are an irregular shape that I have never seen before. If someone can help me identify the shape, and help me find the section properties, I will be able to analyze the joist. I have attached a picture of the cross section in question.
Some browsing around past threads has led me to the macomber v-beam series of chords. I have downloaded some information on the sizes they made, and this has been a great help. I guess I'm wondering if anyone can tell me if this was the manufacturer for sure, or if other companies were also making this shape.







RE: help identifying an irregular OWSJ chord
May I suggest that you contact D. Matthew Stuart, P.E., S.E., F.ASCE, SECB
He has written a series of articles on antiquated structural systems for STRUCTURE magazine. I know that he has an extensive catalog of proprietary joist information.
Adam Vakiener, P.E.
RE: help identifying an irregular OWSJ chord
http://www.slideruleera.net/contributions.html
RE: help identifying an irregular OWSJ chord
SRA...thanks again...from all of the "old guys" at E-T
RE: help identifying an irregular OWSJ chord
It looks similar to the Anthes Joist which was built in Toronto, Ontario until it went out of business (I forget the year). Page 27 of their catalog is attached.
If it is an Anthes joist, I would advise you to check the eccentricity of the end diagonals where they meet supports. As I recall, excessive eccentricity was the reason given for the collapse of a number of joists in several buildings. I understand this was the reason they went out of business.
BA
RE: help identifying an irregular OWSJ chord
BA
RE: help identifying an irregular OWSJ chord
RE: help identifying an irregular OWSJ chord
Yes, the chords were cold formed and conformed to CSA S136-1963, which means they were or should have been weldable. I have no reason to believe they were not weldable.
Furthermore, Anthes regularly load tested their joists taken from the production line under the supervision of an independent testing company. See attached.
On the projects I looked at, because the beam spans were not consistent, the EOR selected beams with a top flange varying from 5" to 12" in width. In cases where the c/c span of joist was constant, the fabricator provided joists satisfying the widest beam flange. The end diagonal cleared the 12" flange by 1/2" but cleared the 5" flange by as much as 4" which resulted in a bending moment too high for the joist shoe to resist.
I surmise (although I do not know for certain) that the load test did not replicate this condition and that instead, the end block of the testing device was located close to the end diagonals of the joists.
I was hoping that andrew705 would see my post because in all probability, the joists he is checking were fabricated by Anthes so he would want to have a look at end eccentricities on all joists, particularly where beam flange widths are variable.
BA
RE: help identifying an irregular OWSJ chord
thank you very very much for your very helpful response. i will look into the eccentricity on monday when i am back in the office. your post makes me feel a little bit better because i was using the macomber data for analysis, but my boss will be much happier to see me using specs from a canadian manufacturer. the buildings that i keep finding with this joist are all in the greater toronto area, so i think you're really on to something here.
i'll update you on monday when i get back to the office, thanks again!
RE: help identifying an irregular OWSJ chord
BA
RE: help identifying an irregular OWSJ chord
The two pages attached are not very clear, but illustrate the joist eccentricity. Some of the joists which did not fail had even larger eccentricities than those that did. In one case, the eccentricity was reported to be 8".
BA
RE: help identifying an irregular OWSJ chord
i find it very interesting that this company might have had problems with failure, as we're finding more and more of these joists that need to be analyzed. i assume by the age of these buildings that they probably dont share the same problem, but i will definitely keep the eccentricity in mind.
im trying to find more information on the company. do you have any articles about the collapses, or the closure of the company?
your help is greatly appreciated.
RE: help identifying an irregular OWSJ chord
So far as the collapses are concerned, I believe that excessive eccentricity between the supports and the end diagonals combined with lack of fusion in the weld between the end diagonal and the top chord were largely responsible for the collapses.
BA
RE: help identifying an irregular OWSJ chord
I have exactly the same issue as the one described in the OP. My building is located in Hamilton Ontario. The tag of some of the OWSJ I am interested in read " ANTHES STEEL PRODUCTS LTD M79 1751" and others read " GREAT WEST STEEL INDUSTRIES LTD N80 1751" The members of all joists are similar to the attached.
You have been a great help in identifying these joists, I wonder if you can post the load tables for 31" depth with 38' span. Thanks.
RE: help identifying an irregular OWSJ chord
I tried to send six pages but got an error message. Here are the first three.
BA
RE: help identifying an irregular OWSJ chord
BA
RE: help identifying an irregular OWSJ chord
Just wondering where you got this manual, and if there is any way I can see the rest of it, somehow.
The information you've posted in this thread so far has been hugely useful, but my company continues to see these joists quite frequently, and the more information I can gather the better.
Just to give you some background, the solar division of my company specializes in the design of roof mounted solar photovoltaic arrays, which is big business in Ontario right now. A huge part of what we do is analysing existing roof structures to ensure they meet current codes with an excess capacity that would suit the installation of a solar panel system... not knowing a lot about these joists we've had to take some conservative assumptions that have ruled a few buildings out, which doesnt make our clients too happy. Any more help you could lent us would be greatly appreciated.
RE: help identifying an irregular OWSJ chord
thanks again for all the help so far!
RE: help identifying an irregular OWSJ chord
I received the Anthes catalog many years ago from Anthes Steel Products. There was the original catalog entitled "Design Manual AA3" and a smaller document entitled "Supplement to Design Manual AA3". The supplement contained two newer V-shaped chord members similar but a little thicker than the sections in the original catalog.
Counting the outside cover, the original catalog has 30 pages and the supplement has 12. I don't know offhand where you can find these documents, but there is a business card attached to the supplement under the name of:
Anthes Steel Products Limited
Campbell A. Roylance, P. Eng.
Regional Sales Manager
491 Portage Avenue, Winnipeg 2, Manitoba
Telephone 774-2535
Res. 837-3348
I have no idea whether or not Mr. Roylance is still living in Winnipeg, but if he is, you might find some luck there.
Alternatively, if there were as many structures incorporating Anthes joists in your area as you say, I would expect you could find other consultants nearby with a copy of the catalogs. Engineers wouldn't throw such things away, would they?
BA
RE: help identifying an irregular OWSJ chord
Dik
RE: help identifying an irregular OWSJ chord
That is a whole bunch of eccentricity on those joist seats. Wouldn't want to be responsible for those jobs.
RE: help identifying an irregular OWSJ chord
There is not much to be gained by copying the Anthes catalog. It specifies chord sizes for various joist designations but it does not specify the web members used. You would need shop drawings for that.
It appears there were at least three types of end diagonal members which Anthes used. In some, the bottom chord was bent up to form an end diagonal then bent again to form the bottom of the shoe. In others, an open seam tube was used for both interior and end diagonals. The outside diameters of the listed Anthes O.S. Tubes do not necessarily conform to those in the sketch provided by Ailmar in his post. The end diagonal in Ailmar's sketch consists of two flat bars which are not shown anywhere in the catalog and whose yield strength is unknown.
If there are specific questions you have about the Anthes joist, I will try to find the answer from the catalog, otherwise you are simply going to have to use your best judgment.
BA
RE: help identifying an irregular OWSJ chord
Looking again at your chord sections, they do not seem to have the same profile as the Anthes joists in my catalog. Be careful about what you assume in assessing an existing roof.
BA
RE: help identifying an irregular OWSJ chord
RE: help identifying an irregular OWSJ chord
Indeed, they are different and I was going to say that. In my case, some of the vertical tubes, which their ends were flattened, the flattened ends were placed perpendicular to the axis of the chords leaving small length for the weld. BA, Thank you very much for helping.
RE: help identifying an irregular OWSJ chord
The joists with double flats as end diagonals are neither Anthes nor Great West Steel joists.
BA
RE: help identifying an irregular OWSJ chord
RE: help identifying an irregular OWSJ chord
RE: help identifying an irregular OWSJ chord
RE: help identifying an irregular OWSJ chord
BA
RE: help identifying an irregular OWSJ chord
RE: help identifying an irregular OWSJ chord
When Great West Steel purchased the assets of Anthes Steel Products in November 1971, I was moved from Winnipeg to Mississauga as the General Sales Manager for GWS ( Eastern ). Previous to this move I had been the the Western Canadian Sales Engineer for Anthes Steel Products from May 1961, through to July 1968, where after I became affiliated with GWS's Edmonton and Saskatoon manufacturing plant, to the purchase date of Nov. 1971
In these roles I became closely famliar with the attributes of the cold roll formed process and the application to this process to that of joist fabrication. In the 1970's there were 2 other fabricators who attempted to produce OWSJ's using CRF sections, York Steel and Frankel Steel. We really should meet as there is a thread of history here that will need be understood, if your current roof review work is to be made easier.
RE: help identifying an irregular OWSJ chord
As much as I would love to get together with you guys for a beer and a discussion on steel joists, I don't know if I can justify the travel costs. The other two guys, Ailmar and Andrew705, however are both from Ontario. I am surprised they haven't been in touch with you by now.
BA
RE: help identifying an irregular OWSJ chord
I provided your contact info to the engineer who is working on this job. However, I believe he decided to reinforce the roof by adding new joists to maintain the same loads currently applied on these joists.