Title: Punching Shear Strength of Slabs with Openings and Supported on Rectangular Columns

Author(s): Susanto Teng, H. K. Cheong, K. L. Kuang, and J. Z. Geng

Publication: Structural Journal

Volume: 101

Issue: 5

Appears on pages(s): 678-687

Keywords: column; flat plate; punching shear; strength

DOI: 10.14359/13390

Date: 9/1/2004

Abstract:
This paper summarizes one part of the research program on flat plate structures conducted jointly by the Nanyang Technological University (NTU) and the Building and Construction Authority (BCA)-Singapore. The paper focuses on the punching shear strength of slabs with openings and supported on rectangular columns. Twenty slab specimens had been tested under concentrated loads and it was found, as expected, that the stresses in the slabs were concentrated mostly around the shorter sides of the rectangular columns. Openings reduce punching strength considerably and, if the use of an opening is unavoidable, the best place for the opening is along the longer side of the column. An equation for calculating the punching strength of slabs is proposed based on the ACI 318-02 approach. The influence of a flexural reinforcement ratio is taken into consideration. The proposed shear stress formula also takes into account column rectangularity. The performance of the proposed equation together with the ACI 318-02 equations has been verified with 223 data from literature as well as with the 20 slab specimens described herein. The proposed equation is found to be accurate.