Fig. (8) Contour plot of the physical stress components Σ₍₁₁₎ (a) and Σ₍₂₂₎ (b). In (c), plot of the physical stresses Σ₍₁₁₎ (dashed line) and Σ₍₂₂₎ (solid line), at x₁ = a/2, versus x₂. Notice that the stress Σ₍₁₁₎, at x₁ = a/2, represents the thrust per unit length applied horizontally to the supporting arch/wall. In (d), plot of the physical stress Σ₍₁₁₎, at x₂ = b/2, versusx₁. To read the pictures dimensionally, the load per unit area p must be given in kNm^-2, and the projected stress components, are generalized stresses given in kNm^-1.