The　compressive　behavior　and　failure　mode　of　corroded　steel　tube　short　columns　were　investigated　through　experimental　research　and　numerical　simulation.　An　equivalent　relationship　between　salt　spray　corrosion　and　natural　corrosion　environments　was　established　to　reveal　the　evolution　of　mechanical　properties　in　corroded　steel.　The　process　of　surface　corrosion　was　analyzed　at　both　macroscopic　and　microscopic　levels.　Subsequently,　axial　pressure　tests　were　conducted　on　the　short　columns　of　corroded　steel　tube　tubes.　The　findings　indicated　a　significant　decrease　in　the　ultimate　bearing　capacity,　ductility,　and　initial　stiffness　of　the　samples　with　increasing　corrosion　time.　Following　112　days　of　salt　spray　corrosion,　the　ultimate　bearing　capacity　decreased　by　33　%　for　uncoated　specimens　and　17.8　%　for　coated　specimens,　while　the　ductility　coefficient　decreased　by　32.16　%　and　29.82　%,　and　the　initial　stiffness　decreased　by　60.47　%　and　42.27　%,　respectively.　Additionally,　a　method　for　randomly　generating　corrosion　pits　based　on　3D　scanning　results　was　proposed,　and　a　finite　element　model　incorporating　the　morphology　characteristics　of　these　pits　was　developed,　with　simulation　results　aligning　with　experimental　findings.　Finally,　a　prediction　model　for　the　ultimate　bearing　capacity　of　corroded　steel　tube　short　columns　was　established　using　the　GM　(1,1)　model　in　grey　system　theory,　demonstrating　a　prediction　error　of　less　than　5　%.　©　2025　Institution　of　Structural　Engineers