shear value for staples in wood
shear value for staples in wood
(OP)
Does anyone know where one can find tables that give shear values for staples in wood? I don't find it in NDS. I have a site built truss that has been put together with 3/4" plywood gussets and 7/16" crown 16 ga. x 1.75" staples that I must evaluate.
THanks,
THanks,





RE: shear value for staples in wood
They may even have a more recent one.
Mike McCann
MMC Engineering
RE: shear value for staples in wood
RE: shear value for staples in wood
RE: shear value for staples in wood
I had found info in ESR-1539 and also in IBC 2006 Table 2306.4.1. By comparing staple & nail values in both tables in the same plywood into DF, then looking at NDS nail values, I backed out separate values for the staples I mentioned in 19/32" plywood of 51 lb & 53 lb. I was encouraged that they were so close from 2 separate tables by 2 slightly different methods. I'm curious to see what the above mentioned reports give.
RE: shear value for staples in wood
How can you be sure the staples went in correctly and just didn't "bend over" when they hit the main members.
I think I might analyze each joint and add the appropriate amount of nails or screws.
RE: shear value for staples in wood
I pulled one of the staples out to check it. It went in fine. Staples have been used for years and they do have some shear value. This is only a 17' garage truss with 25 psf snow. I planned on adding nails to bring the strength to what I need, but am finding that there are sufficient staples in it. Whomever built it put a lot in each gusset, each side. Looks well built.
By the way, I could not get ahold of either report mentioned above. They are discontinued. Could not find an updated one. Would either of you above mind either checking my value against your table?
THanks,
RE: shear value for staples in wood
RE: shear value for staples in wood
Table 11 in ESR-1539 (pg. 16), which was easily found online, shows that diaphragms using my staples were just barely stronger in every case than the same diaphragm using 6d sinker (0.099 in) nails. I would think it would be conservative to use the NDS value for a 6d which is 53 lb.
msquared48, do you have a value for my staples listed above from your old ICBO Report 2403 for me to compare to? I'm using 19/32" ply into DF.
RE: shear value for staples in wood
If you can get a copy of the report, you will find the value in Table VII, Page 9 of 28 of the report. The value is listed at the very bottom line of the table.
Hope this helps.
Mike McCann
MMC Engineering
RE: shear value for staples in wood
It looks like you are deriving the staple value from a diaphragm table as well, correct?. If I understood you right, you meant that a 180 plf value corresponded with 6" o.c. edge spacing. I think by your method, that would be 90 lb per staple, right? I think that would still need to be decreased by 33% per most diaphragm tables I have seen, based on the load duration assumed by the table, getting us to 67 lb.
Are you sure about that method? When you look at say a diaphragm for 8d commons @ 6" o.c. for 15/32" ply in DF, you get 260 plf. Your method would give the 8d a 130 lb value, then decreasing by 33% to get 98 lb. NDS nominal value for 8d in same conditions is 73 lb.
I found some other older engineering that gave a 53 lb. value to the same staple. That seems most reasonable to me so far.
RE: shear value for staples in wood
Mike McCann
MMC Engineering
RE: shear value for staples in wood
Mike McCann
MMC Engineering
RE: shear value for staples in wood
RE: shear value for staples in wood
RE: shear value for staples in wood
So the theoretical and more conservative value of the Mode IV equation would be 46 lb. The 52 lb I derived from Table 11 diaphragm loads and NDS is based on testing, and is reasonable in my opinion. Close enough.
Hopefully this run-around will help someone else in the future.