Title: Behavior and Design of Multistory Building Frames of Unbonded Post-Tensioned Concrete
Author(s): James E. Wailer and John E. Zimmerman
Publication: Journal Proceedings
Appears on pages(s): 357-362
Keywords: continuity (structural); flexural strength; frames; post-tensioning;structural design; unbonded prestressing.
Designing post-tensioned multistory building frames frequently results in significant construction cost savings. The reluctance of structural engineers, clients, and developers to employ post-tensioning in building designs is often the result of misunderstanding the behavior and design requirements of this type of structure rather than the extra cost entailed in contractor, labor, and material evaluation as compared with other conventional construction methods. This paper illustrates the structural behavior of post-tensioned building frames, presents a moment-balancing design procedure for unbonded, draped, post-tensioned tendons, and discusses several aspects of primary and secondary post-tensioning forces which must be considered to properly design mild steel reinforcement in accordance with ACI 318-77.