Title: Case Study of Effects of Post-Tensioning the Beams in a 45-Story Building
Author(s): Mark Fintel and S. K. Ghosh
Publication: Journal Proceedings
Appears on pages(s): 184-191
Keywords: beams (supports);bending moments;colums (supports);creep properties;high-rise buildings;post-tensioning;prestressed concrete;prestressing;shear properties.
This paper is a case study of the effects of story-by-story post-tensioning on the various parts of a structure, during construction as well as service life. Mathematical models of a progressively growing multistory building are analyzed in stages corresponding to the separate stressing of each floor. A determination is made as to whether a significant portion of the applied prestressing force may be wasted in bending the ridgid walls or columns, thereby reducing the effective prestress in the beams. The possible effects of creep shortening of the beams due to post-tensioning are also studied. It is found that no special sliding details, which have sometimes been used, are nesscessary for the post-tensioned beams in the typical floor of a multi-story building.