New shear transfer system for concrete‐filled steel tube (CFST) columns

Concrete-filled steel tube (CFST) columns are frequently used in construction due to their high ductility and improved loadbearing capacities. At beam-to-CFST column joints, gusset plates welded the outer face of tube, specific elements should ensure shear transfer between inner concrete core. The current systems studs, internal rings, angles, plates, bars, tab stiffeners, etc. Although good, these also have disadvantages, such as slowing down process, complexity execution, greater material consumption restricting flow when pumping into tube. UPCCFST is a new connection system that enhances bond strength CFST consists punching inwards produce crown-shaped protrusions act connectors. This speeds up simplifies connections, does not restrict casting has economic environmental advantages. Push-out tests were performed evaluate strength. improvement using been compared with reference conventional columns. increased by 6.67 times for SHS 200x4 specimens 2.89 110x2 specimens. paper explains system, prototyping testing most important results observations.