Fig. (3) Examples of singular stress fields. Singular (right) and regular (left) statically admissible stress fields, corresponding to a concentrated load applied at a point on the boundary: (a). Singular (right) and regular (left) statically admissible stress fields, corresponding to regular data: (b); on the left of Fig. (b), the regular stress is a constant biaxial stress field; the regular part of the stress field on the right of Fig. (b) is represented by uniaxial stresses having discontinuities along the interfaces depicted with double lines. Singular stress inside a reinforced concrete beam: (c); Uniaxial stresses emanate from the upper boundary, concentrated compressive stresses have support on a curved line (represented by a double line in the picture), tensile concentrated stresses have support on the solid straight line at the bottom (the rebar). Below the curved line the stress is zero.