Push-out test and analysis of steel pile caps strengthened with perfobond shear connectors

In this study, a push-out test was performed on steel pile caps strengthened with newly proposed perfobond shear connectors, and the test results were analysed and subsequently discussed. The newly proposed perfobond connector can greatly simplify the complicated processes required for the conventional pile cap strengthening method with steel rebars, such as the distribution of reinforcing bars, their anchorage into concrete and the use of shear keys. In total, six specimens were manufactured and tested. Test parameters included the type of strengthening method, infilled concrete depth and the number of shear keys. The applied load-deformation curve was plotted for all test specimens and their failure modes were identified. Effects of the test parameters on the peak load are examined in this study. Three-dimensional nonlinear finite-element analysis was also performed and its results were compared with experimental results, confirming the effectiveness of the proposed perfobond reinforcing method.