Experimental and numerical study of double-through plate connections to CFST column

Abstract

This paper proposes an innovative connection known as double-through plate connection, in which two plates pass through a slotted square column with the concrete infill. The type of connection can be used to connect the steel hollow structural section (HSS) beam to the concrete-filled steel tube (CFST) column. Three specimens were tested under cyclic loading. The failure modes, hysteretic performance, stiffness, strength, ductility and classification of the joints were evaluated. The results revealed that the type of connection exhibited similar behaviors with single plate connection. The characteristics of the connection effectively reduced the stress level on the column flange and improved stress distribution. Then a nonlinear finite element (FE) model was developed and verified by the experimental results in terms of moment-rotation relationship and failure mode. The parametric analyses were utilized to explore the effect of hole shape and bolt pretension force on the connection performance. In addition, bolt slippage and load transfer mechanism in the joint region were also discussed.