Kahn's patented invention is a steel bar of 45-degree diagonal "wings" as several minor members that are rigidly attached to the main member.
The idea of the "wing" technique is that the stresses are distributed throughout the main reinforced beam.
The steel then doesn't slip within the hardened concrete.

Another significant feature of the Kahn Trussed Bar and Kahn System of reinforced concrete was its resistance to fire.
Kahn's patented invention is a steel bar of 45-degree diagonal "wings" as several minor members that are rigidly attached to the main member. The idea of the "wing" technique is that the stresses are distributed throughout the main reinforced beam. The steel then doesn't slip within the hardened concrete.
Another significant feature of the Kahn Trussed Bar and Kahn System of reinforced concrete was its resistance to fire.
Kahn system