2) A machine frame is made of steel having Sy= 400 MPa and Say= 250 MPa. When loaded in a test fixture, the stresses were found to vary linearly with load. Two points on the surface were found to be most critical. With a 4-kN test load, stresses at these points were: point a, 0₁ = 200 MPa, 0₂ = 100 MPa; point b, 0₁ = 150 MPa, 0₂ = -100 MPa. Compute the test load at which the frame will experience initial yielding according to the (a) maximum-normal-stress theory, (b) maximum-shear-stress theory, and (c) maximum-distortion-energy theory. Discuss briefly the relative validity of each theory for this application. Considering all the information available, what is your best judgment of the value of the test load at which yielding would actually be expected to begin? σ1 02= 100 MPa a 02 0₂=-100 MPa 9 02 ₁= 200 MPa σ1 = 150 MPa

2) A machine frame is made of steel having Sy= 400 MPa and Say= 250 MPa. When loaded in a test fixture, the stresses were found to vary linearly with load. Two points on the surface were found to be most critical. With a 4-kN test load, stresses at these points were: point a, 0₁ = 200 MPa, 0₂ = 100 MPa; point b, 0₁ = 150 MPa, 0₂ = -100 MPa. Compute the test load at which the frame will experience initial yielding according to the (a) maximum-normal-stress theory, (b) maximum-shear-stress theory, and (c) maximum-distortion-energy theory. Discuss briefly the relative validity of each theory for this application. Considering all the information available, what is your best judgment of the value of the test load at which yielding would actually be expected to begin? σ1 02= 100 MPa a 02 0₂=-100 MPa 9 02 ₁= 200 MPa σ1 = 150 MPa

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 7.2.19P: At a point on the surface of an elliptical exercise machine, the material is in biaxial stress with...

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