ps_01.tex:
Beam AB measures k·l while BC is l. Bending Moment
diagrams have blue-colored boundaries and are conventionally positive
under the structure; yellow lines indicate the Shear diagram which is
drawn positive upwards.
Four cases are presented here. Note the behaviour of these ones:
k=2: BM always negative in the whole structure
k>2(=2.5): Reaction in C (positive shear) directed downwards
Introducing k=0.333, on obtain the same sketch of Example 6.