Plywood Floor Panel Under Concentrated Load

[civil_4343]

Plywood floor decking supported by joists. Plywood has a concentrated load between joists. I used APA Panel Specification Design Tables to check the bending capacity, but I'm not sure what the critical failure mode of shear is. What is the check for punching shear through the plywood? Does shear in the plane of panel, and panel shear through thickness need to be checked?

 

[dauwerda]

What is the load, if fixed in one place why not just put blocking below it? Typically you will run into deflection issues well before you run into strength issues with plywood.

 

[phamENG]

Agree with dauwerda. Creep is going to be a problem. Even if you load it up now and all is fine, you'll get a depression at that point load 5 to 20 years from now. Ever been in a house with a floor sloping toward a wall that doesn't have joists below it?

Even if the plywood can take it, that blocking is cheap and will likely improve the long term performance of the floor system.