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This study continued the investigation into the mechanical properties of high strength concrete filled steel tubular columns, (HSCFST). The test results for slender columns show that the load bearing capacities and maximum displacement ratio (the ratio of displacement to the initial length at peak load) of the column decreases as slenderness ratio, determined as the ratio of the length to diameter, increases. The test results for eccentrically loaded columns show that when the slenderness ratio is kept constant, the load bearing capacity and maximum strain decrease as the eccentricity ratio increases, with the eccentricity ratio defined as the ratio as the ratio of eccentricity to radius. The formula for calculating the load bearing capacities of slender columns and the eccentrically loaded columns are presented in the paper. These formulas are designed for inclusion in design code documents.

This study investigated the mechanical properties of High Strength Concrete filled steel tubular short columns (HSCFSTSC) with length to diameter ratio (L/D) of 3.5.The strength of concrete used to fill the steel tubular columns ranged from 54MPa to 116MPa. The test results showed that using a steel tube as confinement can significantly improve the ductility and compressive strength of core concrete. The magnitude of compressive strength increase of core concrete was directly proportional to the Confinement Index, , and the extent of improvement of the ductility increases as the  increases. For thoroughly improving the ductility of core concrete, the Confinement Index  should be equal or larger than 0.48. The formula used to calculate the load bearing capacity of HSCFSTSC was given out.

An experiment was undertaken to investigate the effect of mineral admixtures, w/b, external chloride solution concentration, and carbonation on chloride binding capacity of cementitious paste. The test method was based on equilibrium method. Test results show that incorporating metakaolin, blastfurnace slag, steel slag, and flyash increases chloride binding capacities by 65.9%, 55.3%, 43.9%, and 26.8% respectively. Increasing external chloride concentration and w/c ratio can improve the chloride capacity of pure cement paste. Carbonation of cement paste will reduce the chloride capacity. Chloride binding do affect the durability of reinforced concrete in saline environment.