L2: Tri-Axial Stress & Strains Flashcards
(14 cards)
What are Auxetic Materials
Materials with a negative Poisson’s ratio, i.e expand latyerally when stretched longitudinally.
How does Uni-axial (1D) stress result in Tri-axial (3D) strains on a cube
How can the normal strains εx, εy, and εz that result from the tri-axial (3D) stress state be described by using Hooke’s Law
How can the three normal strain equations can be rearranged to give the 3 equations for the normal stresses
Derivation to find the three normal strain equations using matrices
Are there lateral or Poisson effects on the shear stress-strain relationships
There are no lateral or Poisson effects on the shear stress-strain relationships.
Equations for Shear Stress on a Cube
What is bulk Modulus, K, and what two things does it link together
The Bulk Modulus, K, is a measure of how incompressible the material is.
For materials that are compressible v<0.5 (most engineering materials), the relationship between the mean stress σm, and the resulting change of volume, δV, of a linear elastic isotropic solid is defined by the Bulk Modulus.
Derivation to find the Volumetric strain and Bulk Modulus for this Cube
How can you calculate the Volumetric Strain of this Cube
How can you calculate the Bulk Modulus Strain of this Cube
How can you adapt Shear Stresses in Hooke’s law by removing the the z-axis?
