Thoughts on Plate joinery

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Any body have any comments or thoughts on this type of jointery? How does it compare in strength to traditional joints. How about attatching knee braces with 2 lag bolts like in these pictures? Basically, these barns are built out of green wood with no cut jontery, all timbers butted up and plates installed, or just lag bolts holding them together.
url=http://www.sandcreekpostandbeam.com/products/nebraska/pics/NebrBarn11.jpg]picture 1
[/url]url=http://www.sandcreekpostandbeam.com/products/nebraska/pics/NebrBarn1.jpg]picture 2[/url]
url=http://www.sandcreekpostandbeam.com/products/nebraska/pics/NebrBarn8.jpg]picture 3[/url]
url=http://www.sandcreekpostandbeam.com/products/big_barns/pics/GreatPlainsGambrel5.jpg]picture4[/url]
url=http://www.sandcreekpostandbeam.com/products/big_barns/pics/GreatPlainsGambrel7.jpg]picture 5[/url]


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Jim Rogers

[beenthere]

Looks a bit cosmetic to me. I'd wonder about the strength of the joints, as apparently you are as well.

Don"t see the engineering backing behind it but may be there.

As in Pic 2, seems the support beam is a tad bit undersized if someone is going to put any amount of hay in the loft above.

If we lose the pics from this site, this thread won't mean much to the reader in the future. Can you get pics into your gallery? If they are not your own, may not be able to.

[solodan]

I'm sure that the plates and joints are plenty strong, it is almost all you will see out this way as far as post+ beam goes. :-\ Unfortunately, Simpson Strong Tie has such a huge influence out here, that it seems some engineers and building inspectors have been educated that this is the only way to build a structure. : Definately easier to build using this method, but where is the craftsmanship ??? My 8 year old daughter can cut a butt joint. ;)

[Don P]

There is nothing wrong with this type of construction as long as the engineering is done correctly. We all have our personal feelings as to aesthetics, don't confuse that with serviceability. There's more than one way to build. I worked for one fellow who said "I'm spending money I don't have to impress people I don't know". Craftsmanship comes with a hefty labor price tag. There's 2 sides to every coin  ;).

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I'll add some pics to my gallery and change the links to them in the original post when I get a little time. What happens when the wood dries? Do all the bolts need to be tightened?

[Don P]

I looked in 2 books I have both said that bolt holes should be accurate and 1/32 to 1/16" oversize depending on diameter. They should be snug but not crush wood. Nothing about retightening. I can only think that it would be a good idea.

The main bible for that type of construction is the Timber Construction Manual. I bought mine in '85 so its somewhat dated. I think you could probably get it on library loan. It's available on their website aitc.org . It is packed full of details for this type of construction but not cheap.

The NDS has bolting provisions and design data for bolted plates. It has the most current design data. Some of which is new in the '05 edition.

I kept wandering in the NDS. Shear plates and split ring connectors do require tightening until seasoned. They were the most critical bolted connectors I could think of in that regard.

Timberlinx, knife plates and timber rivets are other pretty recent connectors.

One plus to bolted connections is they tend to weaken the recieving member less than some traditional connections  .

[beenthere]

Are we talking 'lag bolts' here, or through-bolts with nuts to tighten?  The first post mentioned lag bolts.
I think there would be a difference, and through bolts would be best.

[Don P]

First, Appendix A in the NDS, A.8 Maintenance;
There shall be competent inspection and tightening of bolts in connections of trusses and structural frames.

I was talking thru bolts, not lags.
I wonder how much difference we're talking about...

...In the NDS tables,
A 6-3/4" thick spf timber with 1/4" sideplates and a 3/4" bolt, loaded perpendicular to grain (weakest way) can safely bear 1670 lbs.

The same timber with 3/4" dia  lagged sideplates on each side = 1060 lbs (530 lbs ea side) (lag must be buried at least 8 diameters)

So roughly a third stronger to through bolt in that one example.

Either lags or bolts, or another fastener can be used, as long as its properly designed.

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In the pictures I attatched, The plates are through bolted. The Knee braces and the joints with no plates are lag bolted.
Thanks for the input so far.