Experimental investigation of thin-walled concrete-filled steel tube columns with reinforced lattice angle

• A series of column tests of thin-walled concrete-filled steel tubes reinforced with lattice angle were presented in this study.
• The load–displacement curves, load–strain curves, failure modes and ultimate capacity of test specimens were obtained.
• The suitability of current design codes for the thin-walled concrete-filled steel tube columns was evaluated.
• A new design method was developed for the thin-walled concrete-filled steel tube columns reinforced with lattice angle.

Experimental investigation of thin-walled concrete-filled steel tube columns with reinforced lattice angle was conducted in this study. The lattice angle was designed to reinforce the concrete-filled steel tube columns by increasing the percentage of steel cross-sectional area. Column specimens having different lengths ranged from 500 mm to 3500 mm were tested. The behavior and strengths of concrete-filled steel tube columns with lattice angle were investigated. In addition, concrete-filled steel tube columns having the same size but without reinforced lattice angle were also tested for comparison. Material properties of the concrete and steel used in the test specimens were measured. The test strengths are compared with the design strengths calculated using the AISC Specification and Eurocode for the design of composite structural members. A new design method was also proposed for the concrete-filled steel tube columns with reinforced lattice angle. It is shown that the design predictions from the proposed method agree with test results well.