The planes on which σ1 and σ2 act are oriented at 2θp from the planes of σx and σy respectively in the circle and at θp in the element.. The stresses on an arbitrary plane can be determi
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4 The principal stresses σ1 and σ2 are on the σ axis (τ = 0)
5 The planes on which σ1 and σ2 act are oriented at 2θp from the planes of σx and σy (respectively)
in the circle and at θp in the element
6 The stresses on an arbitrary plane can be determined by their σ and τ coordinates from the circle These coordinates give magnitudes and signs of the stresses The physical meaning of +τ vs –τ regarding material response is normally not as distinct as +σ vs –σ (tension vs compression)
7 To plot the circle, either use the calculated center C coordinate and the radius R, or directly plot
the stress coordinates for two mutually perpendicular planes and draw the circle through the two
points (A and B in Figure 1.5.4) which must be diametrically opposite on the circle.
Special Cases of Mohr’s Circles for Plane Stress
See Figures 1.5.5 to 1.5.9
FIGURE 1.5.4 Mohr’s circle.
FIGURE 1.5.5 Uniaxial tension.
FIGURE 1.5.6 Uniaxial compression.
FIGURE 1.5.7 Biaxial tension: σx = σy (and similarly for biaxial compression: – σx = – σy ).
FIGURE 1.5.8 Pure shear.