So comparing 2" plywood (assuming it is properly glued and screwed) to LVL (1.75")
Plywood - E = 8GPa
LVL 2.0E = E = 13.8 GPa
Tread is 12" wide
EI plywood - 8 x 305 x 50 x 50 x 50 / 12 = 25.4 .......
EI LVL - 13.8 x 305 x 44.5 x 44.5 x 44.5 / 12 = 30.1.......
LVL is stiffer.
No I was not aware - I just looked it up. Thank you. I am surprised that there is no difference in youngs modulus in the plank direction...interesting. I would have thought that they manufacture and orient the strands so that strong axis is stiffer than weak axis.
Yes - I was thinking about screwing and glueing the 2 layers of plywood. 1.5" - 1.75" screws, both ways would make it stiff. I'm just curious if anyone has the E for LVL (lowest grade) about the weak axis. Is it different from the published value about the strong axis.?
I want to build a stair case and clad the treads, so the appearance of the tread is not important. I am wondering whether to use 2 layers of 1" plywood or 1.75" LVL laid flat. I can't find the modulus of elaasticity for the LVL about the weak axis. The stair treads are 48" wide x 12".
Thanks!
I have sound absorption coefficients for a material that was obtained through testing. I have the sound absorption coefficients at various frequencies as well as overall NRC, SAA and αw.
I would like to be able to translate this to a decibel drop. How many decibels will be reduced with this...
