Title:
Punching Shear Strength Analysis of Reinforced Concrete Flat Plates With Spandrel Beams
Author(s):
Y. C. Loo and M. Falamaki
Publication:
Structural Journal
Volume:
89
Issue:
4
Appears on pages(s):
375-383
Keywords:
columns (supports); connections; failure mechanisms; moments; flat concrete plates; floors; punching shear; reinforced concrete; shear strength; spandrel beams; torsion; two-way slabs; standards; Structural Research
DOI:
10.14359/3015
Date:
7/1/1992
Abstract:
An analytical procedure is presented for evaluating the punching shear strength Vu of the corner and edge connections of reinforced flat plates with spandrel beams or torsion strips. Vu is defined as the net ultimate column reaction at the contraflexure point. By considering the equilibrium of the slab-column-spandrel connections, three linear equations are established for the bending and torsional moments and shear forces acting therein. An analysis of the interaction of the spandrel beam with the adjoining slab leads to the fourth equation. Intermediate quantities in these equations, including the shear force and moment acting along the front face of the column, are evaluated using semi-empirical formulas. This reduces the number of independent unknowns to four. An explicit formula for Vu is obtained by condensing the four equilibrium and interaction equations. A comparative study is carried out based on the authors' own model test data and those published by others. The results indicate that the proposed analytical procedure is accurate and reliable. It is also found that the procedure adopted in the Australian Standard AS3600-1988 sometimes gravely overestimates the strength of the corner connections.