This article presents advantages in the application of precast/prestressed concrete in structural frames. Using pretensioned concrete components in conjunction with a composite cast-in-place concrete topping creates a lighter structural system than an all-cast in-place structure. Shoring pretensioned beams and slabs before adding the composite topping can reduce member size even further. Extending reinforcing steel from the precast components creates functional joinery systems that can be used instead of, or in conjunction with, a number of other connection methods, including mechanical couplers. A complete system of precast units can be integrated to form a building frame that behaves monolithically, with sufficient strength, stiffness, and durability to resist seismic loadings.
