Experimental research on axial compressive performance of graphite tailings cement-stabilized soil-filled steel tubular stub columns

To enhance the utilization efficiency of graphite tailings and address the stability challenges of hollow steel tubular members, a novel composite structural member named graphite tailings cement-stabilized soil-filled steel tubular (GTCS-FST) column is proposed. Axial compression tests on 15 stub columns were conducted, and the influences of curing age and core material compaction pressure on the axial mechanical performance of the composite column were investigated. The contributions of steel tubes and GTCS cores to axial bearing capacity were analyzed, and the composite interaction under axial loading was clarified. Experimental results demonstrate that GTCS significantly enhances the load-bearing capacity (by 49.4%–91.5%), initial stiffness (by 49.6%–84.9%), and ductility of hollow steel tubular columns. This kind of composite member exhibits high load-bearing capacity, superior ductility, and environmental friendliness, suggesting its engineering application could achieve dual objectives of solid waste utilization and structural performance enhancement.