Hertz contact theory can be used to determine the stresses due to contact between two spheres, which can be used approximate frictionless contact between the patellar and femoral components of a total knee replacement. Part a) Show on a sketch how the stresses at the surface vary from the centre of contact to the edge of contact. Part b) Make a sketch of an infinitesimal element of material at the centre of contact that shows the stress components. Identify the maximum principal stress, and write an expression for the maximum shear stress. Part c) Sketch a graph that shows how the maximum contact pressure varies with load and in a sentence explain why the curve has the shape it does.

Hertz contact theory can be used to determine the stresses due to contact between two spheres, which can be used approximate frictionless contact between the patellar and femoral components of a total knee replacement. Part a) Show on a sketch how the stresses at the surface vary from the centre of contact to the edge of contact. Part b) Make a sketch of an infinitesimal element of material at the centre of contact that shows the stress components. Identify the maximum principal stress, and write an expression for the maximum shear stress. Part c) Sketch a graph that shows how the maximum contact pressure varies with load and in a sentence explain why the curve has the shape it does.

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter7: Analysis Of Stress And Strain

Section: Chapter Questions

Problem 7.7.15P: A brass plate with a modulus of elastici ty E = 16 X 106 psi and Poisson’s ratio a = 0.34 is loaded...

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