On the free surface of a steel machine element E 210 Gpa v
     On the free surface of a steel machine element (E = 210 Gpa, v = 0.31), strain rosette configuration shown in the figure measures the following values: epsilon_a = -115 mu epsilon epsilon_b = 750 mu epsilon epsilon_c = -15 mu epsilon.  Determine the strain components epsilon_x, epsilon_y and gamma_xy at this point  Determine the principal strains and the principle angles. Pair up & clearly state the associated strains & angles  Determine the maximum in-plane shear strain  Determine the \"out of plane\" principal strain, i.e. epsilon_z or epsilon_p3 and clearly state the criterion for your decision  Determine the absolute maximum shear strain  Sketch deformations & distortions, i.e., plot the principal strains and the maximum in plane shear strain on an appropriate strain element to also indicate the rotation of axes  Making use of the results you have found from part (b), determine the principal stresses  Determine the shear modulus G for the steel material  making use of the result you have found from part (c) & (h), determine the maximum in plane shear stress  Making use of the results you have found from part (g), determine the average normal stress  Sketch the principal stresses, maximum in plane shear stress & the average normal stress on an appropriate stress element(s) to also indicate the orientation of principal planes and maximum shear plane  Making use of the results you have found from part (e) & (h), determine the absolute maximum shear stress.    
 
  
  Solution
taking angle 1 =0, angle 2-= 120, angle 3 -60
Measured strain-1
E/(2(1+v))
Modulus of rigidity
Obtain strain components
ex=-115, ey = 528.33, gxy = =883.35
Principal strains e1 750.06, e2 -115.06, gamma 865.13, angle 0.497
| Measred strain 1 | 1 | x(cos1)2+y(sin1)2+xysin1cos1 | 
| Measured strain-2 | 2 | x(cos2)2+y(sin2)2+xysin2cos2 | 
| Measured strain-3 | 3 | x(cos3)2+y(sin3)2+xysin3cos3 | 
| Normal strain | x | (x/E-vy/E-vz/E) | 
| Normal strain | y | (y/E-vz/E-vx/E) | 
| Normal strain | z | (z/E-vx/E-vy/E) | 
| Shear strain | xy | xy/G | 
| Shear strain | yz | yz/G | 
| Shear strain | zx | zx/G | 
| G | E/(2(1+v)) Modulus of rigidity Obtain strain components ex=-115, ey = 528.33, gxy = =883.35 Principal strains e1 750.06, e2 -115.06, gamma 865.13, angle 0.497 | 

