The cantilever is always treated as allowable stress in a short cantilever, irrespective of the calculations of the designed deep beam.
Symbols:
d - Serviceable height of the cantilever cross-section.
a - Distance between the location of the resultant load and the face of the cantilever support.
L - Length of the cantilever measured to the support face.
Verification of stresses in concrete:
Calculation of reinforcement:
If the loads appear as suspended to the cantilever, the equivalent height of the cantilever cross-section is introduced into calculations as 
. In this case, the load must be transferred by the vertical suspended reinforcement whose percent may be smaller than 0.8fe.