This study focused on the seismic performance of an intermediate unit of scrap tire-granular material composite columns under cyclic loading. A Laboratory test study regarding the dynamic deformation characteristics of the intermediate unit of a scrap tire-granular material composite column was conducted. The hysteresis loops, skeleton curves, stiffness degradation curves, and energy-dissipation capacities of the three specimens with different initial vertical loads were experimentally evaluated. Based on the test results, a restoring force model of the tire-granular material unit is established. The results demonstrated that the external force had a significant influence on the strength of the intermediate unit of the scrap tire-granular material composite column. The area of the hysteresis loop of the tire-granular material unit was large, indicating a good seismic performance. As the initial vertical load increased, the horizontal bearing capacity and lateral stiffness of the intermediate unit of the scrap tire-granular material composite column increased. The calculation results of the skeleton curve and hysteresis curve were in good agreement with the test results. As a base damping material, the scrap tire-granular material composite column is feasible, and provides a new concept for the resource utilization of the original scrap tire.
Keywords: Scrap tire; restoring force model; scrap tire–granular material composite column; seismic performance; the hysteresis loops.