When creating shell sections, why does LS-Dyna have the recommendation to change the shear factor to 5/6 instead of having it be a value of 1? What do you recommend the value should be?
So just to clarify, LS-Dyna is suggesting a value of 0.833 which is the same as 5/6. I recommend that as well, but you will be fine using 1 in a basic simulation. Here's an excerpt from the LS-Dyna manual:
"SHRF: Shear correction factor which scales the transverse shear stress. The shell formulations in LS-DYNA, with the exception of the BCIZ and DK elements, are based on a first order shear deformation theory that yields constant transverse shear strains which violates the condition of zero traction on the top and bottom surfaces of the shell. The shear correction factor is attempt to compensate for this error. A suggested value is 5/6 for isotropic materials. This value is incorrect for sandwich or laminated shells; consequently, laminated/sandwich shell theory is now an option in some of the constitutive models, e.g., material types 22, 54, and 55."
So basically, making this value 0.833 is an attempt to address an issue of the first order shear deformation theory which most shell element formulations are based on.