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STRESS AND STRAIN ANALYSIS OF A HOCKEY STICK. Andrew Mills Jeff Tibbe Brad Vander Veen. Loading Analysis. Loading is due to stick blade striking the ice In bending and torsion The stick bends similar to a bow Elastic energy stored in the bent stick is used to accelerate the puck. Picture.
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STRESS AND STRAIN ANALYSIS OF A HOCKEY STICK Andrew Mills Jeff Tibbe Brad Vander Veen
Loading Analysis • Loading is due to stick blade striking the ice • In bending and torsion • The stick bends similar to a bow • Elastic energy stored in the bent stick is used to accelerate the puck
Picture • The bottom half of the stick looks like a cantilever beam; this is how the load will be modeled
Experimental Setup • Cantilever beam in torsion and bending • Fixed with clamps at midpoint of shaft • Mass hung where stick blade would strike the ice • Strain gage place at fixed end
Comparison • Theoretical and Actual follow the same trends. • Most results had a percent discrepancy of about 15% to 40% • Torsional stress results did not agree as well as bending stress results • Angles of principal stresses and strains agreed (3° vs 5°)
Failure Analysis • Hockey stick yielded when a 70 lb load was applied. • At 60 lbs, the measured maximum principal stress was 49,000 psi • The yield stress for the material was 52,900 psi • The 70 lb load caused a principal stress higher than the yield stress
Discussion • Error in torsional results was higher because it was hard to constrain it • Measurements were very sensitive to slight constraint movements
Conclusion • Stresses and strains in a theoretical analysis agreed well with results found in the actual experiment