Experimental study of connections between concrete-filled steel tubes and reinforced concrete beams

As a composite structure, concrete-filled steel tube columns offer many advantages compared to conventional steel or concrete columns. However, the use of concrete-filled steel tube columns has been limited due to a lack of knowledge and the complexity of connections to such columns. In this paper, a series of tests has been carried out. In the first part of the tests, two full-scale specimens of concrete-filled steel tube connections with steel corbels through the core from a practical project were tested under monotonic loading, and then the results regarding the attainment of the ultimate capacity and the collapse model were presented. In the second part of test, seven reduced-scale specimens with various connection details, such as the ring beam, the plate-and the covered corbel through the core, were tested under monotonic loading and repeated low cycle loading. The test results were discussed in light of improving and optimizing the details of the connections. Finally, some conclusions and suggestions were obtained for the design work.