Static push out test of rectangular steel tube concrete components

The interface bonding behavior of concrete-filled rectangular steel tubular (CFST) members was studied by static push out test system. The influence of two types of core concrete, ordinary concrete and high ductility concrete, on the interfacial bond strength is analyzed, and the failure mechanism and strain distribution characteristics are revealed. The test results show that the ultimate bond strength of high ductility concrete (HDC) specimens is 36 % lower than that of ordinary concrete, but it has more uniform strain distribution characteristics. The research results provide a theoretical basis for the interface design of composite structures.