ANALYSIS OF CONCRETE-FILLED SQUARE THIN-WALLED STEEL TUBULAR STUB COLUMNS WITH STEEL BAR STIFFENERS

摘要

Finite element software ABAUQS 6.5 was used to simulate the axial compressive loading behaviors of concrete-filled square thin-walled steel tubular stub columns with inside steel bar stiffeners,outside steel bar stiffeners,inner reinforcing bar cage. The axial load-displacement curves and the failure mode from finite element analysis agreed with corresponding experimental results well. Through numerical calculation,it studied the longitudinal stress distribution of concrete in the largest section when the concrete-filled square thin-walled steel tubular stub columns with steel bar stiffeners and the plain concrete column with the same size reached the ultimate load. It is found that the longitudinal stress of the core concrete in the concrete-filled square thin-walled steel tubular stub columns with steel bar stiffeners had improved,Steel bar stiffeners can effectively improve ultimate bearing capacity of concrete-filled square thinwalled steel tubular stub columns.