Final answer:
The structural action of a folded plate system of reinforced concrete is analogous to that of a beam.
Step-by-step explanation:
The structural action of a folded plate system of reinforced concrete is analogous to that of a beam. Beams are rigid structures formed of relatively slender pieces, joined to support weight and provide structural stability. In a folded plate system, the concrete plates are folded to create strong structural elements that behave similarly to beams.