Quadratic Failure Theory Tsai-Hill Interaction

[garyjh]

Can you please check the stress report example equations for the Tsai-Hill Interaction. I think the ?11?22 should be preceded by a -ve sign not +ve and the whole section on the bottom half be square rooted.

[Phil]

Hi Gary,

You are correct on both counts.  In the stress report, Eq (141.1a,b) the cross-stress term should be negated and in the margin of safety equations (141.3a,b), the denominator should be square rooted (see attached).  This correction has been made and will be available in the next software update.

The values for the Tsai-Hill margin of safety returned from HyperSizer are already correct and will not be changed.  Therefore, this error is only a typo in the stress report documentation.

Phil

[garyjh]

Phil,
yes forgot to say that the actual margin was correct and that it was just a typo in the report.
Thanks, Gary.