Have you thought about grip width?
A bar will bend differently depending on with wich grip you grab it :
Squat > 1 central pressure point.
Deadlift > 2 shoulder width gripping points
Bench Press > 2 (average) 1,5 shoulder width pressure points
Snatch > 2 (average) 2 shoulder width pulling/pressing points
Clean and Jerk > 2 (average) 1-1,5 shoulder width pulling/pressing points
Do these actually play a role in what you're calculating?
Legendaryblaze wrote : "The mechanical properties can be easily calculated. Moment of Inertia, modulus of elasticity, shear modulus of elasticity, allowable bearing stress, etc. I imagine that olympic bars have a higher modulus of elasticity, lower critical point (concerning buckling) and less stiffness."
These factors will be modified from the bar caracteristics, but also from the grip, the technical specifications of each lift.
- A Clean and Jerk will make your bar bend more because your grip is narrow(er) and you use more weight. Your limbs will operate in a "straight" line hence more load.
- The Snatch will make your bar bend less at it allows use for less weight, as you upper limbs "rotate" to bring the bar up. The wider grip reduces the rotation radius (total distance to achieve the lift), then allowing more load.
So, my thought are :
1) If you only calculate mechanical properties of each tested bar, are you calculating from a UNIQUE central point? Or testing with actual human ergonomic settings?
2) Are you mesuring with equal speed? Taking in account acceleration/deceleration, as with O-lifts you don't need to decelerate your bar (bring it to the ground)?
3) Are you calculating/comparing performance in each lift with the same weight, but with different bars?
4) If so, will you take in account that elasticity and Inertia could modify the lift's achievement? When you stabilise, you "shake" making it more difficult to lift the load...
Hope this helps. If not, please apologise someone really interested in the subject, but with no actual idea in what the goals are (I'm a nurse...).