FOUR-POINT BENDING TESTS ON CONCRETE-FILLED LEAN DUPLEX STAINLESS STEEL RHS BEAMS

Four-point bending tests on concrete-filled lean duplex stainless steel (LDSS) rectangular hollow section (RHS) beams have been presented. A total of 32 beams, including 24 concrete-filled and 8 without concrete infill beams, under pure bending of either major or minor axis was conducted to assess the flexural performance. The RHS had the cross-section aspect ratio of depth-to-width (D/B) varied from 0.50 to 2.01, and overall depth-to-thickness ratio (D/t) varied from 19.9 to 38.6. The nominal cylinder strengths of concrete ranged from 30 to 110 MPa. In this study, the effects of concrete strength on beam ductility and flexural strength were investigated. The beam flexural strengths were compared with the flexural strengths predicted using the American Specification and European Code. It was found that the design flexural strengths predicted by the aforementioned specifications are very conservative. The design flexural strengths predicted by the American Specification are generally found to be slightly more conservative than the European Code.