ISO 12215-5 Effective Plating for Plywood

Dood day for everybody!

Could somebody make it clear for me what is the meaning of the term "effective plating" in the ISO 12215-5? I am particulary interested in plywood on wood construction.

Chapters 11.6 and G.5 state "effective plating" for plywood on wooden stiffeners as 15 times plywood thickness plus the stiffener width.

Does this mean the distance between the stiffeners should be less than the effective plating?

In other words:

The example at G.5.5.1 says that the effective plating for 50x50mm stringer on the 15mm plating is 15*15+50= 275mm

Does it mean that stringers are to be placed not wider than 275mm?

Hope for some answers...

 

It can be said that way too when the stiffeners have same dimensions.

 

When calculating the section modulus of the stiffener you can take a "virtual strip" of the plating to be a part of the second moment area of the stiffener. This virtual strip is "effective plating". This is only possible when the stiffener is glued onto the plate.

In your example, if the stiffener spacing is 250 mm, you couldn't calculate the effective plating wider than 250 mm. If your spacing is 350 mm, you could use 275 mm wide strip as an effective plating.

 

Dear gentlemen! Thank you very much!