Experimental Study of Concrete-Filled Double-Skin Steel Tubular Beams with RHS Inner and Outer Subjected to Pure Bending

In order to investigate the behavior of concrete filled double skin steel tubular beams (CFDST) with RHS(rectangular hollow section) inner and outer, a total of three CFDST beams and one convenient concrete filled steel tube(CFST) with RHS were tested under pure bending load. The parameter varied in the tests was hollow section ratio. The test results show that all specimens have good plastic properties in the loading process. The flexural bearing capacity of the CFDST specimens is better than that of the convenient CFST specimens. Bending moment-deflection relationship curves of CFDST beams subjected to pure bending were analyzed by finite element software ABAQUS,and the calculated results were in good agreement with those of tests.