I am a building structural engineer trying to design a fiberglass sheet to withstand some loading. I am not sure if I got my head straight on this; I am so excited that I found this forum where all the experts in plastic/fiberglass talk:
Basically, it's a 12'x12' sheet, supported at every 4' each way by series of beams, the sheet is supporting some small loading. Using finite element program, I have easily determined the von mises stress in the sheet. It is a E-glass sheet with properties shown below:
Flexural Strength 28,600 psi
Flexural modulus 1.2 x 10^6 psi
Found a structural design manual online from Delta Composites, the manual calls for factor of safety of 2.5 for flexural stress check. Questions:
1. Is it safe to compare the allowable stress of (28,600 psi/2.5) to the maximum von mises stress from my program?
2. To determine the correct deflection, could I use Flexural Modulus as modulus of elasticity in my model?
Thanks for your input in advance.
Basically, it's a 12'x12' sheet, supported at every 4' each way by series of beams, the sheet is supporting some small loading. Using finite element program, I have easily determined the von mises stress in the sheet. It is a E-glass sheet with properties shown below:
Flexural Strength 28,600 psi
Flexural modulus 1.2 x 10^6 psi
Found a structural design manual online from Delta Composites, the manual calls for factor of safety of 2.5 for flexural stress check. Questions:
1. Is it safe to compare the allowable stress of (28,600 psi/2.5) to the maximum von mises stress from my program?
2. To determine the correct deflection, could I use Flexural Modulus as modulus of elasticity in my model?
Thanks for your input in advance.