Seismic Behavior Investigations of the Haunched Joint with Ribbed Anchor Webs in CFDST Structures

Abstract

The haunched joint with ribbed anchor webs in the concrete-filled double steel tubular (CFDST) structure was proposed in this study. The CFDST column and the steel beam were connected by vertical ribbed webs, which were anchored inside the column and connected to the beam web by the bolted connection, and haunches were welded to shift plastic hinges from the joint core to beam ends. The cyclic loading test was conducted on three beam-to-column joint specimens. Seismic behaviors including failure modes, strain and stress responses, hysteretic curves, ductility, and energy dissipation capacity were respectively analyzed. Besides, a finite element (FE) modeling was completed by ABAQUS in consideration of geometric and material nonlinearity. The validity of FE modeling was checked by comparisons between FE results and test results, and research results confirmed that the beam-to-column rotation and the shear deformation in the joint core were small owing to the restriction from the configuration of haunches. Then parametric investigations on connection constructional details, geometric dimensions, material strength, and axial compression ratios, were made to study seismic behaviors of the haunched joint with ribbed anchor webs. It showed that the selected parameters except concrete strength had certain influences on bearing capacity, ductility, and energy dissipation, and corresponding practicable design suggestions were proposed for the application of haunched joints with ribbed anchor webs in CFDST structures.

Seismic Behavior Investigations of the Haunched Joint with Ribbed Anchor Webs in CFDST Structures

“…A preprint has previously been published in Research Square [35], and this is an updated version of the manuscript.…”