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thanks alot bro

As you know that we allow the yielding in the flexural members. In shearwall, we also allow flexural yielding but do not allow shear yielding. We also do not want the brittle failure we always like to have ductile yielding. In case of shearwall we want the flexural yielding at certain locations. We can not allow the yielding at unwanted locations. When earthquake pushes a shearwall (structure) in one direction the in shearwall there will be Tension on one side (one corner) and Compression on the other side (other corner). This can be reversed. We do not want the shearwall to fail in brittle form and specially at corners. So code required that concrete to be confined by the horizontal reinforcement. In this case the fc' of that corners increased significantly and there will be no yielding at these locations. We need the shearwall to be yielded so we provide minimum flexural reinforcement in the NON BOUNDARY ZONE ELEMENTS. So that the shearwall can yield at the middle locations in case of earthquake. The remaining reinforcement ( Total Flexural Reinforcement - minimum reinforcement) is provided in the BOUNDARY ZONE ELEMENTS. For this actually we need to check the strain limits obtained by Non Linear Time History Analysis but code also provides a method to calculate boundary zone lengths. So thats the reason for confined zones. The length of Boundary zone also depends u[on Thanks Muneeb

They are doing it right. It depends on you. It is the beauty of the structures that they will behave the way you designed them. When reducing the torsion modifier for beams that are failing to a value approx equal to 0 then watch for the increased moments in slabs. If you put the reinforcement in slab for additional moment then it is ok! It depends upon the relative stiffness of beam and slab that how much load beam will take (Torsion, moment etc).