1st Asia-Pacific Conference on FRP in Structures, APFIS 2007, Hong Kong, China, 12 - 14 December 2007, vol.1, pp.233-238
© 2007 International Institute for FRP in Construction.This study presents the results of experiments conducted on a new economical and easy to install strengthening technique for flat plates against punching failures. Four test specimens that were simply supported along four edges with corners free to lift up, representing the interior slab-column connection were tested. The concrete strength and tension longitudinal reinforcement ratio of the specimens were 30 MPa and 1.41%, respectively. Self-manufactured CFRP dowels were placed around the column stubs of the flat-plate specimens as vertical shear reinforcement. As a result of experiments, it was observed that the vertical load carrying capacities of the strengthened specimens were increased up to 33.4% relative to reference specimen. In addition, the test results indicated that the post-punching capacities of the specimens were also increased up to 135.5% relative to control specimen. The ultimate load capacities and failure modes of the test specimens were compared with the ACI 318-05 provisions. The test results show that the proposed FRP retrofit technique can be used successfully to enhance punching shear capacity of slab-column connections.