To make a TIN (triangles) you can select both 3d points and polygons. They must be together in the same selection set.
The break lines must join other points in the set and/or the end points and vertices of all polygons/polylines will become a part of the triangulation.
Arcs will be divided up into segments.
Line segments must not cross.
These line segments included when the TIN is created are considered "soft" break lines.