steel flitch plate buckling

[AlpineEngineer]

Everything I have found regarding steel flitch plate design suggests that the plate must be sandwiched between wood members to prevent buckling. I have a situation where the builder wants to bolt the plate to an existing beam and we don't have the width to add another wood member, thus the plate will be on the outside of the member, no sandwich.

Can't I take my max bending stress and apply it to a slender column equation using my spacing between my bolts for my effective column length and then determine if the plate will buckle? I am thinking there has to be a tight enough bolt spacing to where the plate won't buckle and I can avoid the sandwich idea. Any of you ever done this?

Thanks a ton,

 

[phuduhudu]

You are right. It doesn't have to be a sandwich at all. Normally it is because you are using the timber to hide the steel as an architectural feature but there is nothing to stop you doing as you suggest and using the bolt spacing as the buckling distance for the steel plate. You would then also have to ensure that the timber member was stiff enough over the span to prevent buckling and that is a more complex issue.

Carl Bauer

http://www.bauerconsultbotswana.com