LVL flat-wise bending

[bouk715]

Has anyone come across material properties for standard LVL plies (Microllam or similar) with load applied to the wide face? Specifically I'm looking at an exterior header application in a high wind area, so some of the wall wind load will be transferred to the header. Weyerhauser has load-span tables for headers, but I'm not sure if these are applicable to all wind speeds?

I'm assuming there would be some sort of reduction in Fb and E since the wood is engineered to be loaded from a specific (i.e edgewise) direction?

And feedback is appreciated!

 

[dhengr]

Those values should be pretty good, as are those for the normal bending orientation, since not much is changed. In the manufacturing the strands, chips or laminations or oriented for best advantage w.r.t. normal stresses (bending normal stresses) and those are in the same direction in either case. But, the wood species used, the glue resins used and the exact manufacturing process really influence the final mechanical properties. So, it’s best to know what brands are available in your area and then ask that particular manufacturer, the exact questions you asked in your OP. They will have literature for you, on their products.

 

[focuseng]

Also: Get the ICC code evaluation report off MFG website or product literature. All values are published in these to satisfy product code approval.

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MAP

 

[bouk715]

Thank you both...very useful information. I was able to download the ICC report for Microllam and it had the information (plank loading) that I was looking for. In case anyone is interested, Fb was higher and Fv was lower for plank loading vs edge loading.

 

[dhengr]

Not too surprising. There will be some good outer plys which are now the top and bot. fibers. But, then the max. horiz. shear stress will run parallel to the plys and glue lines near mid thickness, and these plys might be of a slightly lesser quality too.