Research on hysteretic performance of a semi-rigid energy dissipation connection for precast cladding panels

Abstract

A novel semi-rigid energy dissipation connection (SEDC), capable of transitioning the precast cladding panel from a rigid connection to a flexible connection with the primary structure as the seismic action increases, is proposed in the present study. The combination of the bending part and friction part endows the connection with the ability to provide adjustable sliding force and sufficient energy dissipation for the precast cladding panel. The design methods of SEDC, including the elastic stiffness, the yield force, the yield displacement, and the bear capacity, are proposed, followed by a coordinated design method between the precast cladding panels and the primary structure based on SEDC. Fourteen SEDC specimens are designed and tested under monotonic and cyclic loading tests to investigate the semi-rigid workability of SEDC and to evaluate the influence of design parameters of the bending and friction parts. Two working processes, which are the static friction process and the sliding friction process, are clearly reflected by the monotonic test results. The cyclic test results indicate that the SEDC specimens demonstrate satisfactory plastic development with full hysteretic curves, stable load capacity, reliable deformation ability, and favorable energy dissipation ability. The U-shaped bending plates exhibited a track-like deformation pattern without any observed tears or cracks. The NAO friction pads demonstrated a fragmented damage pattern, while the Brass friction pads demonstrated a linear scratch damage pattern. SEDC specimens equipped with Brass friction pads exhibited better low-cycle fatigue performance, which can be attributed to the favorable wear resistance of the Brass material. In addition, finite models of SEDCs are established and validated based on Abaqus. The combined working mechanism of SEDC, including the contribution ratio of load capacity and dissipated energy from the bending part and the friction part, is clearly revealed. Furthermore, the influence of parameters including the thickness (t), width (B), straight section length (l), radius (R), and height (h) of the bending part, as well as the pre-tightening force (pc) and the friction coefficient (f) of the friction part, are also summarized based on both the experimental and numerical analyses. Further discussions, including the calculation of the seismic behavior factor and the measurements for accurate construction, are conducted.