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Stresses in Thin-walled Pressure Vessels (I). (Hoop Stress). (Longitudinal Stress). Stresses in Thin-walled Pressure Vessels (II). Stress State under General Combined Loading. Plane Stress Transformation. Mohr’s Circle for Plane Stress. Principal Stresses. Maximum Shear Stress.
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Stresses in Thin-walled Pressure Vessels (I) (Hoop Stress) (Longitudinal Stress)
Typical Rosette Analysis εmax εa = εx εb = εx/2 + εy/2 + γxy/2 εmin εc = εy gmax εa = εx εmax εb = εx/4 + 3εy/4 + γxy/4 εmin gmax εc = εx/4 + 3εy/4 - γxy/4
Stress Field in Beams Stress trajectories indicating the direction of principal stress of the same magnitude.
Dilatation and Bulk Modulus For the special case of “hydrostatic” loading ----- σx = σy = σz = –p where DV/V is called Dilatation or Volumetric Strain. Define Bulk Modulus K as
Failure Criterion for Ductile Materials(Yielding Criterion) σ1 σ1 |σ1| = σY σ2 |σ2| = σY σ2
Comparison of Yielding Criteria Tresca Criterion (Max. Shear Stress) |σ1| = σY |σ2| = σY |σ1 – σ2| = σY Von Mises Criterion (Max. Distortion Energy)