EXPERIMENTAL RESEARCH ON SHORT T-SHAPED STEEL COLUMN WRAPPED WITH CERAMSITE CONCRETE UNDER AXIAL COMPRESSION

A kind of T-shaped steel column wrapped with ceramsite concrete was proposed. With the good thermal insulation and impermeability performance of ceramsite concrete, it has been used as covering material to improve column's insulated and fireproof performances. Axial compression test and finite element analysis were carried out on two 1 720 mm high T-shaped columns to obtain the mechanical properties. The effects of stirrup end and steel web welded or not on the bearing capacity of specimens were discussed. The results indicated that the obvious cracking and ceramsite concrete's falling off did not occur until arrived the ultimate load, which proved that the concrete and steel had good bonding effects. Benefiting from the concrete cover, the strength of the steel column was fully utilized and the steel might reach the yield strength. Because ceramsite concrete provided an effective restraint for the inner steel, the local and overall buckling of the steel column were avoided, and the ductility and bearing capacity of the specimen were improved. Welding stirrup ends on the web of T-shaped steel had little effect on the bearing capacity of the specimen. The connections between the stirrup ends and steel were strengthened, which constrained the deformation of longitudinal reinforcement and reduced the damage of concrete.