Seismic behavior of connections between H-beams and L-shaped column composed of concrete-filled steel tube mono-columns connected by double vertical plates

Abstract

L-shaped column composed of concrete-filled steel tube mono-columns connected by double vertical plates (LCFST-D) is widely used in high-rise buildings because it can be embedded into walls and is flexible for architectural design. Due to the asymmetrical cross-section of the LCFST-D, the traditional form of one side of the H-beam and LCFST-D connection is the widen-flange plate joint and other sides are vertical stiffener joints. However, the strength and stiffness of the former are relatively low. Thus, in this study, the π-shaped joint was introduced to make the flexural capacity of both sides of the connection are close. Five full-scale specimens were casted for pseudo-static tests, and finite element models (FEM) calculation by Abaqus was introduced to provide a supplementary calculation. The results showed that the whole connection had a good seismic performance. The strength and stiffness of the vertical stiffener joint and the π-shaped joint were closed. Subsequently, parameter analysis was performed for further study of the factors of the flexural capacity. Finally, the calculation formulas for the flexural strength of the connection were derived, and the formulas of the shear strength were quoted. The calculation results were conservative and the errors were acceptable, thus, these calculation methods could be used in actual projects.