Title: Ultimate Strength of Corner Panels of Post-Tensioned Flat Plates

Author(s): P. R. Chakrabarit

Publication: Structural Journal

Volume: 84

Issue: 1

Appears on pages(s): 54-60

Keywords: building codes; flat concrete plates; loads (forces); post-tensioning; prestressed concrete; strength; tests; two-way slabs; unbonded prestressing; yield line method; Structural Research

DOI: 10.14359/2793

Date: 1/1/1987

Abstract:
In ACI 318-83, new formulas were introduced for determining the ultimate design stress of unbonded post-tensioning tendons. The requirement for bonded steel was revised. A complete guide for the design of prestressed flat plates with different boundary conditions is still required. No test has yet been reported for the strength evaluation of corner panels. In this paper, an attempt is made to study the cracking and limit state behavior at failure of prestressed concrete four-panel flat plates having two-way continuous parabolically draped unbonded post-tensioning tendons. The test specimens closely simulate the corner panels of a flat plate floor system having simple wall supports along the perimeter. The effects of different arrangements of post-tensioning tendons and the effects of additional mild steel are also studied. The ultimate loads are calculated using various code-suggested formulas and the results are compared to the experimental values. Recommendations are also made for further research.